DEVELOPMENTAL DEFORMITIES OF THE LOCOMOTOR APPARATUS (DEVELOPMENTAL DISLOCATION OF THE HIP. SCOLIOSIS. CLUBFOOT. TORTICOLLIS.)
DEVELOPMENTAL DISLOCATION OF THE HIP
Among the many difficulties surrounding the diagnosis and treatment of deve-lopmental dislocation of the hip (DDH) is the abbreviation itself. The second “D” in DDH can refer to either dysplasia (a term first used by Helgenreiner), dislocation, or both. In this lecture, for brevity, the acronym DDH will be used as a generic term encompassing the many variations and stages of congenital hip dysplasia, subluxation, and dislocation.
The term DDH is now preferred over congenital dislocation of the hip (CDH) since many cases have been reported in which the child’s exam was normal at birth and later was found to be subluxated or dislocated. Therefore the term DDH is a better description of the problem.Incidence, etiology: The incident of developmental hip dysplasia (DDH) reported in the literature varies from 3 to 16 per 1000. The female-to-male ratio is prîximately 5:1. The exact etiology of congenital hip dysplasia remains unknown. DDH is more common in some families, with Wynne-Davies (1970) noting that relatives of children with hip dysplasia had lax ligaments and slightly shallow acetabule, as compared to normal control. Ethnic factors play a role, with an incidence of 25-50 cases per thousand in Lapps and North American Indians and an extremely low incidence in Chinese and black Africans. African mothers carry their babies with the hips widely adducted. This position contributes to hip stability and maximizes acetabular development. Environmental factors such as infant swaddling and use of cradle boards, which produce unnatural excessive early hip extension, may contribute to the high incidence in certain ethnic groups.
Being first born, female, or arriving in the breech position increases the chances for DDH. The slightly loose hip capsule, further stretched by a difficult intrauterine, allows the femoral head to gradually deform the acetabular rim (labrum). In severe cases the hip completely dislocates, whereas in less severe cases the hip is only loose (dislocatable or subluxatable).
DDH must be recognized and treated early. A poorly centrated hip will not last a lifetime. The medical system’s goal should be to find DDH at earliest possible age, when the deformity in the biologically plastic infant skeleton is readily corrected by re-positioning, the femoral head in the acetabulum. Early treatment should decrease the incidence of early adult degenerative arthritis as a sequela of untreated or inadequately treated DDH. Uniform early diagnosis is a difficult goal to achieve. Some babies are never examinåd, and some examiners have little experience in differentiating normal from abnormal. Many babies have hip “clicks” or slightly “loose”hips, which may confuse the examiner. Pure hip dysplasia (shallow acetabulum, never dislocated) even more difficult to detect. Reviews of adults with hip arthritis have many had unrecognized childhood hip disorders. Although early diagnosis and treatment are advised, DDH is difficult to treat at any age.
Diagnosis of DDH: Associated Disorders as an Aid in Diagnosis: Military pilots flying over a desert and looking for a river bed do not look for water; instead they look forvegetation (something green) that only grows near rivers or steams. Similarly, to avoid missing DDH, you should know the condition associated with it. Any baby with one (or more) of these associated conditions should be elevated to the “high suspicion for DDH” group. These conditions are:
§ Full breech presentation;
§ First born;
§ Family history of DDH;
§ Metatarsus varus;
§ Torticollis, calcaneovalgus;
§ Other congenital anomalies (cardiac, renal);
§ Any syndrome
Specifics of the newborn exam: The examiner’s goal is it to gently palpate, adduct, abduct, flex, extend, and translate the infant’s hip joint in the attempt to demonstrate abnormal mobility.
In 1935, Mario Ortolani, an Italian pediatrician, became very interested in a 5-month-old baby whose mother worried because she felt a “click” every time she washed the child’s bottom. The mother showed Ortolani how to produce the “click” with adduction and abduction. He took a x-ray, which demonstrated DDH. He began examining all babies and treated neonates with a positive sign by triple diapering. In 1936 he published a paper and hip click became known all over the world as Ortolani’s sign.
Barlow later described an adduction maneuver to aid in diagnosing a dislocatable hip. In his “provocation” test, the unstable hip is dislocated.
Most physicians combine the Ortolani and Barlow maneuvers when examining infant hips. Because subluxability is the most common abnormality encountered, it is necessary to begin with Barlow component of the exam.
The Barlow component includes gentle adduction of the hip, first bringing it to midline and then actually adducting the hip 10-20°. As adduction proceeds, a gentle posterior force is applied to determine whether the femoral head will “slide ” posteriorly within the acetabulum (subluxatable) or actually dislocate over the acetabular rim “positive Barlow”. Then the hip is moved into abduction, with gentle traction is applied to relocate the femoral head. This sequence is repeated several times to establish the degree of laxity.
With the Ortolani maneuver, the hip can be dislocated posteriorly (this component includes gentle movement of the 90° flexed hip from 20° of adduction – with Barlow component) and then reduced by gently abduction the hip and providing anterior pressure (with the fingers) over the greater trochanter. A dislocated hip will reduce with a “clunk”, this is called “positive Ortolani sign”. This sign better felt than heard.
Soft-Tissue Clicks: soft-tissue noises (pops, snaps) can be felt (rarely heard) in both normal and abnormal hips. The origin of hip clicks is unknown. Many normal hips pop, and subluxatable hips are often silent.
After your physical exam the hip should be described as:
1. Normal (with or without soft-tissue click).
2. Subluxatable – capsular laxitó.
3. Dislocatable – Barlow-positive.
a. Reducible – Ortolani-positive;
b. Not reducible – “teratologic”
Examination in the Older Infants: In the baby 1 month of age older, restricted hip abduction may be the only physical findings, particularly in a dysplastic hip. Positive Ortolani and Barlow signs are noted less often, and hip instability gradually disappears. By the age of 2-3 months, the hip becomes fixed in the dislocated position. Other clinical signs can be noted: asymmetric thigh skin folds and apparent femoral shortening. When the child’s hip and knees are flexed to 90°, the knee heights are uneven. The femur is not short on the dislocated side, but rather the femoral head is positioned more posteriorly, out the acetabulum. This is known as a “positive Galeazzi sign”.
Roentgenograms confirm the initial diagnosis.
Neonatal X-Rays Examination: The following guidelines may help to determine the proximal (cranial) position of the femoral head .
a) The arch of the superior ramus of the pubis and the arch of the medial femoral metaphysis normally forms Shenton’s line. Shenton’s line is broken when the hip is subluxated or dislocated;
b) Hilgenreiner’s line is drawn trough both triradiate growth cartilage zones. This line is described the distances to localize the metaphysis in relation to the triangulate cartilage;
c) Perkin’s line is dropped perpendicular to the lateral margin of the bone acetabulum;
d) The acetabular index is constructed by drawing a line along the bonyacetabular roof, intersecting Hilgenreiner’s line. The normal angel is less than 30° at birth and 20° at age 1 year.
Ultrasound (US). Graft (1983) in Australian and others have clarified the value of ultrasound in detecting and staging DDH. Hip ultrasound studies (US) are gradually replacing hip x-rays for diagnosis of DDH in infancy. The US exam is particularly valuable in the infant under age four months when the ossific nucleus is not yet ossified.
The most reliable clinical signs for the diagnosis of DDH in children over the age of 1 year:
§ The leg is shortened on the dislocated side, halting gait;
§ Gaddling gait in case of DDH of both hips;
§ The apex of the greater trochanter may be palpable lying over Roser's and Nelaton's line;
§ Positive Trendelenburg sign;
§ On palpation of the inguinal region the displaced hip will be absent
Newborn treatment: Methods of newborn treatment include maintenance a newborn’s hip in abduction and flexion on each side. Due to special devices are used.
Abduction diapering and traditional devices, such as the Frejka pillow do not maintain the hip in adequate flexion and abduction to reduce a dislocated hip. The Freyka pillow (and many modifications) worked well for mild cases but did not flex the hip enough to reduce DDH in a difficult case. These methods and devices should be used only for subluxatable (not for dislocated or dislocatable hips), only in neonates and only for 1 month.
Adolph Lorenz, a prominent Viennese surgeon, developed and promoted a closed-reduction–spica-cast technique that dominanted European and North American DDH treatment in the 20th century. His method included a vigorous manipulative reduction, including a sharp blow with the open hand (karate-like) to the groin to avulse (and lengthen) the adductor longus tendon origin. The forced reduction was performed without prior traction. The child was then casted in 90° of hip flexion and 90° of abduction, a posture Salter later labeled the „frog position“. After several months, the child was changed from the Lorenz position (first position) to the Lange position (second position) of abduction and internal rotation.
The so-called „frog position“ cast is thought to be a major contributor to the high incidence of avascular necrosis (AVN) of the femoral head following closed reduction of DDH (30 – 40%) in many series.
Lorenz position (first position)
Lange position (second position) of abduction and internal rotation.
The Pavlik Harness
In 1958, Arnold Pavlick, a Czechoslovakian orthopaediñ surgeon, developed an innovative harness for treating DDH in infants. The method has become a standard treatment method for newborn infants with a dislocatable or dislocated hip.
Application of the Pavlcsk harness: the straps are adjusted to maintain hip abduction at 30 – 40°, with about 8 – 10 centimeters (width of a clenched fist) between the knees with attempted hip adduction. Hip flexion should be maintained between 100° and 120° for the dislocatable and dislocated hip and between 90° and 100° for subluxatable–dysplastic hips.
The baby‘s active kicking stretches contracted hip adductors, leads to spontaneous reduction of the dislocated hip and promotes acetabular development.
Partial hip stability as usually achieved 1–3 weeks after initiation of treatment. In the routine case, x-ray exam is performed out of harness after 4 weeks of treatment. When the hip is clinically and roentgenologically stable, the harness can be removed for a half-hour daily for bathing baby and washes the harness.
Another x-ray is performed out of harness at about age 3 months. If acetabular development is adequate after 10–12 weeks of harness wear, to night- and naptime wear is performed. For infants with a dislocated hip treated at birth, the average duration of harness wear is 3 months full-time and 1 month part-time. Harness wear is discontinued when the clinical and roentgenologic exams are normal. Although difficult to use in older children, Pavlick harness reduction is clearly safer than cast reduction, at any age. Complication: a) inferior dislocation of the hip; b) femoral nerve palsy; c) avascular necrosis of the femoral head.
Treatment for DDH diagnosed at age 6–18 months: After about age 6 months, the hip becomes more fixed in the dislocated position, making reduction with the Pavlik harness more difficult. In these cases long-leg traction is applied to both legs. In most cases 2–3 weeks of skin traction followed by closed reduction (this method is generally used in North America). Children less than 1 year of age are placed on the traction frame with their hips at 90° of flexion. In children aged 1–2 years a more longitudinal pull is used, with the hips at about 45° of flexion and 30–45° of abduction. Approximately 1–2 pounds of weight are applied to each leg. The traction is usually maintained for 3 weeks. After traction, closed reduction under anesthesia is attempted. If the reduction is adequate, the child is then casted in 90° of hip flexion and 90° of abduction (the Lorenz or “first” position). After one month the child is changed from the Lorenz position to the more functional positions (“second” and ”third” positions). This is achieved with help of various devices (the splints of Shneiderov, CITO, Vilenskiy etc). These splints are applied together to conservative methods of rehabilitation (exercise therapy, massage, general therapy).
A European traction frame designed for progressive even severe abduction. This method is designed for prolonged traction, with a goal of actually reduction the hip with traction alone. The traction is usually maintained for 3 weeks. The cast is then applied; however, the hip has already been reduced. When the method of the conservative treatment was not effective, the child should have open reduction.
In children over the age of 1 year, or any with difficult dislocation (great laxity, high dislocation), an anterior open reduction plus capsulorrhaphy is indicated.
In children over the age of 2 years, primary femoral shortening, open reduction, capsulorraphy, and often pelvic osteotomy is advised.
Summary: Overall goals in the management of infantile DDH include:
1. Early diagnosis;
2. Safe and effective hip reduction without AVN;
3. Minimizing psychological stress to the child and family;
4. Correction of the acetabular dysplasia, and a hip that lasts a lifetime.
This can be best achieved by using the Pavlick harness in newborn and young infants, with traction followed by closed or open reduction for older babies. Each treatment method is designed to maximize the chance for deep concentric reduction while minimizing the risk for AVN. This is sometimes a difficult balancing act. Hip spica casting for DDH is associated with a higher incidence of AVN than is Pavlick harness reduction. Implementation of a safe, predictable traction, closed versus open reduction, and hip spica casting sequence requires skill and experience
Developmental Dysplasia of the Hip
The term congenital dislocation of the hip dates back to the time of Hippocrates. This condition, also known as hip dysplasia or developmental dysplasia of the hip (DDH), has been diagnosed and treated for several hundred years. Most notably, Ortolani, an Italian pediatrician in the early 1900s, evaluated, diagnosed, and began treating hip dysplasia. Galeazzi later reviewed more than 12,000 cases of DDH and reported the association between apparent shortening of the flexed femur and hip dislocation. Since then, significant progress has been made in the evaluation and treatment of DDH (see image below).
Numerous radiographic measurements have been used to assist in the evaluation of developmental dysplasia of the hip (a typical radiographic evaluation is described in this image). From an anteroposterior radiograph of the hips, a horizontal line (Hilgenreiner line) is drawn between the triradiate epiphyses. Next, lines are drawn perpendicular to the Hilgenreiner line through the superolateral edge of the acetabulum (Perkin line), dividing the hip into 4 quadrants. The proximal medial femur should be in the lower medial quadrant, or the ossific nucleus of the femoral head, if present (usually observed in patients aged 4-7 mo), should be in the lower medial quadrant. The acetabular index is the angle between the Hilgenreiner line and a line drawn from the triradiate epiphysis to the lateral edge of the acetabulum. Typically, this angle decreases with age and should measure less than 20° by the time the child is 2 years old. The Shenton line is a line drawn from the medial aspect of the femoral neck to the inferior border of the pubic rami. The line should create a smooth arc that is not disrupted. If disrupted, it indicates some degree of hip subluxation is present.
The definition of developmental dysplasia of the hip (DDH) is not universally agreed upon. Typically, the term DDH is used when referring to patients who are born with dislocation or instability of the hip, which may then result in hip dysplasia.
A broader definition of DDH is simply abnormal growth of the hip. Abnormal development of the hip includes the osseous structures, such as the acetabulum and the proximal femur, and the labrum, capsule, and other soft tissues. This condition may occur at any time, from conception to skeletal maturity. The author prefers to use the term hip dysplasia because he believes this term is simpler and more accurate. Internationally, this disorder is still referred to as congenital dislocation of the hip.
More specific terms are often used to better describe the condition; these are defined as follows:
Subluxation – This is incomplete contact between the articular surfaces of the femoral head and acetabulum.
Dislocation – This refers to complete loss of contact between the articular surface of the femoral head and acetabulum.
Instability – This consists of the ability to subluxate or dislocate the hip with passive manipulation.
Teratologic dislocation – This refers to antenatal dislocation of the hip.
The overall frequency of developmental dysplasia of the hip (DDH) is usually reported as approximately 1 case per 1000 individuals, although Barlow believed that the incidence of hip instability during newborn examinations was as high as 1 case per 60 newborns. According to his study, more than 60% of hip instability became stable by age 1 week, and 88% became stable by age 2 months, leaving only 12% (of the 1 in 60 newborns, or 0.2%) with residual hip instability.
The etiology of hip dysplasia is not clear, but this condition does appear to be related to a number of different factors. One such factor is racial background; among Native Americans and Laplanders, the prevalence of hip dysplasia is much higher (nearly 25-50 cases per 1000 persons) than other races, and the prevalence is very low among southern Chinese and black populations. An underlying genetic disposition also appears to exist in that a 10-fold increase in the frequency of hip dysplasia occurs in children whose parents had developmental dysplasia of the hip (DDH) compared with those whose parents did not.
Other factors possibly related to DDH include intrauterine positioning and sex, and some of these are interrelated. Female sex, being the first-born child, and breech positioning are all associated with an increased prevalence of DDH. An estimated 80% of persons with DDH are female, and the rate of breech positioning in children with DDH is approximately 20% (compared with 2-4% in the general population). The prevalence of DDH in females born in breech position has been estimated to be as high as 1 case in 15 persons in some studies.
Other musculoskeletal disorders of intrauterine malpositioning or crowding, such as metatarsus adductus and torticollis, have been reported to be associated with DDH. Oligohydramnios is also reported to be associated with an increased prevalence of DDH. The left hip is more commonly associated with DDH than the right, and this is believed to be due to the common intrauterine position of the left hip against the mother's sacrum, forcing it into an adducted position. Children in cultures in which the mother swaddles the baby, forcing the infant's hips to be adducted, also have a higher rate of hip dysplasia.
Developmental dysplasia of the hip (DDH) involves abnormal growth of the hip. Ligamentous laxity is also believed to be associated with hip dysplasia, although this association is less clear. DDH is not part of the classic description of disorders that are associated with significant ligamentous laxity, such as Ehlers-Danlos syndrome or Marfan syndrome.
Children often have ligamentous laxity at birth, yet their hips are not usually unstable; in fact, it takes a great deal of effort to dislocate a child's hip. Therefore, more than just ligamentous laxity may be required to result in DDH. At birth, white children tend to have a shallow acetabulum. this may provide a susceptible period in which abnormal positioning or a brief period of ligamentous laxity may result in hip instability. However, this characteristic is not as true for children of black descent, who have a lower rate of DDH.
Early clinical manifestations of developmental dysplasia of the hip (DDH) are identified during examination of the newborn. The classic examination finding is revealed with the Ortolani maneuver; a palpable "clunk" is present when the hip is reduced in and out of the acetabulum and over the neolimbus. A high-pitched "click" (as opposed to a clunk) in all likelihood has little association with acetabular pathology. Ortolani originally described this clunk as occurring with either subluxation or reduction of the hip (in or out of the acetabulum). More commonly, the Ortolani sign is referred to as a clunk, felt when the hip reduces into the acetabulum, with the hip in abduction.
To perform this maneuver correctly, the patient must be relaxed. Only one hip is examined at a time. The examiner's thumb is placed over the patient's inner thigh, and the index finger is gently placed over the greater trochanter. The hip is abducted, and gentle pressure is placed over the greater trochanter. In the presence of DDH, a clunk, similar to turning a light switch on or off, is felt when the hip is reduced. The Ortolani maneuver should be performed gently, such that the fingertips do not blanch.
Barlow described another test for DDH that is performed with the hips in an adducted position, in which slight gentle posterior pressure is applied to the hips. A clunk should be felt as the hip subluxes out of the acetabulum.
The clinical examination for late DDH, when the child is aged 3-6 months, is quite different. At this point, the hip, if dislocated, is often dislocated in a fixed position. The Galeazzi sign is a classic identifying sign for unilateral hip dislocation (see image below). This is performed with the patient lying supine and the hips and knees flexed. The examination should demonstrate that one leg appears shorter than the other. Although this finding is usually due to hip dislocation, realizing that any limb-length discrepancy results in a positive Galeazzi sign is important.
The Galeazzi sign is a classic identifying sign for unilateral hip dislocation. To elicit the sign, the patient lies supine and the hips and knees are flexed. The examination should demonstrate that one leg appears shorter than the other. Although this appearance is usually due to a hip dislocation, realizing that any limb-length discrepancy results in a positive Galeazzi sign is important.
Additional physical examination findings for late dislocation include asymmetry of the gluteal thigh or labral skin folds, decreased abduction on the affected side, standing or walking with external rotation, and leg-length inequality.
Bilateral dislocation of the hip, especially at a later age, can be quite difficult to diagnose. This condition often manifests as a waddling gait with hyperlordosis. Many of the aforementioned clues for a unilateral dislocated hip are not present, such as the Galeazzi sign, asymmetrical thigh and skin folds, or asymmetrically decreased abduction. Careful examination is needed, and a high level of suspicion is important.
Note: Any limp in a child should be considered abnormal. The diagnosis can be quite variable, but an underlying etiology must always be pursued.
Of primary importance is making the diagnosis of hip dislocation or dysplasia. Once this diagnosis is made, the patient should be examined to be sure there is no underlying medical or neuromuscular disorder. Proximal femoral focal deficiency can masquerade as hip dysplasia and often manifests similarly. Because the femoral head does not ossify, the radiographic appearance also may be deceiving. Other neuromuscular disorders can manifest as dysplasia later in life, such as Charcot-Marie-Tooth disease.
Using expected-value decision analysis, Mahan et al, of Children's Hospital in Boston, found that the screening strategy associated with the highest probability of having a nonarthritic hip at the age of 60 years was to screen all neonates for hip dysplasia with a physical examination and to use ultrasonography selectively for infants who are at high risk. The expected value of a favorable hip outcome was 0.9590 for the strategy of screening all neonates with physical examination and selective use of ultrasonography, 0.9586 for screening all neonates with physical examination and ultrasonography, and 0.9578 for no screening.
Indications for surgery are met if the results of the surgery would be better than the results of the natural progression of developmental dysplasia of the hip (DDH). The natural history of hip dysplasia depends, in part, on the severity of the disease, bilaterality, and whether or not a false acetabulum is formed.
Unilateral dislocations result in significant leg-length inequality, with a gait disturbance and possibly associated hip and knee pain. In addition, Hip pain commonly manifests as knee or anterior thigh pain due to the innervation of the hip joint (obturator and femoral nerve distribution). Typically, true hip pain is identified as groin pain. The development of a false acetabulum is associated with a poor outcome in approximately 75% of patients. Bilateral hip dislocation in a patient without false acetabuli has a better overall prognosis. In fact, a case was reported of a 74-year-old man with no history of hip or thigh pain whose dislocated hips were only discovered shortly before his death.
Indications for treatment depend on the patient's age and the success of the previous techniques. Children younger than 6 months with instability upon examination are treated with a form of bracing, usually a Pavlik harness. If this is not effective or if the hip instability or dislocation is noted when the child is older than 6 months, closed reduction is typically recommended, often with the administration of traction before the reduction.
When the child is older than 2 years or with failure of the previous treatment, open reduction is considered. If the patient is older than 3 years, femoral shortening is performed instead of traction, with additional varus applied to the femur, if necessary. A patient with residual acetabular dysplasia who is older than 4 years should be treated with an acetabular procedure.
Treatment for DDH that is diagnosed when the patient is a young adult can be considered for residual DDH. Unfortunately, radiographic characterization of developmental dysplasia of the hip that is severe enough to lead to early osteoarthrosis is difficult. A center-edge angle less than 16º often has been used to predict early osteoarthrosis, but other authors have found this measurement to be less reliable. Subluxation, defined as a break in the Shenton line, has been demonstrated to be associated with osteoarthrosis and decreased function (see image below).
Numerous radiographic measurements have been used to assist in the evaluation of developmental dysplasia of the hip (a typical radiographic evaluation is described in this image). From an anteroposterior radiograph of the hips, a horizontal line (Hilgenreiner line) is drawn between the triradiate epiphyses. Next, lines are drawn perpendicular to the Hilgenreiner line through the superolateral edge of the acetabulum (Perkin line), dividing the hip into 4 quadrants. The proximal medial femur should be in the lower medial quadrant, or the ossific nucleus of the femoral head, if present (usually observed in patients aged 4-7 mo), should be in the lower medial quadrant. The acetabular index is the angle between the Hilgenreiner line and a line drawn from the triradiate epiphysis to the lateral edge of the acetabulum. Typically, this angle decreases with age and should measure less than 20° by the time the child is 2 years old. The Shenton line is a line drawn from the medial aspect of the femoral neck to the inferior border of the pubic rami. The line should create a smooth arc that is not disrupted. If disrupted, it indicates some degree of hip subluxation is present.
Pavilk harness (1944)
Birth - Six months
The normal growth of the acetabulum depends on normal epiphyseal growth of the triradiate cartilage and on the 3 ossification centers located within the acetabular portion of the pubis (os acetabulum), ilium (acetabular epiphysis), and ischium. Additionally, normal growth of the acetabulum depends on normal interstitial appositional growth within the acetabulum. The presence of the spherical femoral head within the acetabulum is critical for stimulating normal development of the acetabulum.
The anatomy of the dislocated hip, especially after several months, often includes formation of a ridge called the neolimbus. Closed reduction is often unsuccessful at a later date, secondary to various obstacles to reduction. These include adductor and psoas tendon contraction, ligamentous teres, a transverse acetabular ligament, and pulvinar and capsular constriction. With long-standing dislocations, interposition of the labrum can also interfere with reduction.
Relative contraindications to surgery include older age (>8 y for a unilateral hip dislocation or >4-6 y for bilateral hip dislocation, especially if a false acetabulum is not present). Other contraindications to surgery include a neuromuscular disorder, such as a high myelomeningocele or spinal cord injury, or cerebral palsy in a patient who has had a hip dislocation for longer than 1 year.
À. Basic literature
1. Oxford Textbook of Orthopedics and Trauma Source: Oxford University Press (OUP) Author(s): Christopher Bulstrode; Joseph Buckwalter; Andrew Carr; Larry Marsh; JeremyFairbank; James Wilson-MacDonald and Gavin Bowden.1st 2003, ISBN-10: 0192626817 ISBN-13: 9780192626813
2. Clinical Orthopaedic Physical Therapy (94) Janice K. Richardson (Hardback | ISBN10: 0721632572; ISBN13: 9780721632575)
3. Clinical Orthopaedic Rehabilitation (2ND 03) Steven B. Brotzman and Kevin E. Wilk (Hardback | ISBN10: 0323011861; ISBN13: 9780323011860)
4. Bone Dysplasias An Atlas of Genetic Disorders of Skeletal Development Second Edition Jurgen W. Spranger Hardback, Nov 2002 ISBN13: 9780195214741 ISBN10: 0195214749
5. Oxford Handbook of Orthopaedics and Trauma Gavin Bowden Flexicover, Oct 2010 ISBN13: 9780198569589 ISBN10: 0198569580
1. Cornett F.D., Gratz P.G. Modern Human physiology. -New York: Holt, Rinehrt
and Winston, Publishers, 1986. - 502 p.
2. Dennis R. Wenger and Mercer Rang. Art and Practice of Children's Ortho-
paedics/ -Paven Press, Ltd., New York, 1993. - 752 p.
Clubfoot (talipes equinovarus) is a fixed foot deformity of unknown etiology, easily diagnosed at birth. About 50% of cases are bilateral, and 70% of clubfoot occurs in boys. Early passive manipulative correction and serial corrective casting provides complete correction in a few cases, but only partial correction in most. Partially corrected cases require surfery to obtain complete correction, usually performed at age 6–12 months.
History: Clubfoot was depicted in accient Egyptian tomb paintings, and the treatment of clubfoot was described in India as early as 1000 b.c. Hippocrates (circa 400 b.c.) provided follow-up clarification (circa 400 b.c.), describing methods for manipulative correction remarkably similar to current nonoperative methods. manipulation. Mechanical assistive devices (osteoclasts) for correction of clubfoot, developed in the Middle Ages, remained popular and were widely used well into the 20th century. Thomas* wrench was powerfully effective in providing correction, although the plane or structure trough which the correction occurred was not always clear.
That a variety of corrective devices and manipulative methods were developed and subsequently discarded emphasizes the difficulty of regularly achieving permanent results with nonopertive methods. Thomas wrenchThe modern era differs from Hippocrate’s nonoperative method only in its method of maintaining correction (plaster of Paris was first used by Guerin to maintain clubfoot correction in 1836). Hiram Kite, in the 20th century brought Hippocrate’s view back into focus, stressing slow, gentle, manipulative correction with minimal surgery. The popularity of complete correction by serial casting alone has been subdued, to come degree, by the current belief that continuous compression of articular cartilage – without movement– blocks nutricion and leads to cartilage death.
Stromeyer’s method for heel-cord tenotomy  was rapidly applied to clubfoot. Phelps (New York, 1881) promoted extensive medial release in addition to tendo-achilles lengthening. As surgery became safer some advice surgery at a very young age (for infants aged 2–3 months using microscopic loupes), whereas other insist that 1 year is the ideal age.
Etiology, classification: The exact cause of clubfoot remains unknown. Many etiologic theories have been proposed including the following:
1. Intrauterine packing – mechanical factors. This factor alone seems unlikely because the incidence of clubfoot is not increased in twins, large babies, or primiparous babies.
2. Neuromuscular defect. Because disorders such as spina bifida and arthrogrypposis have a high incidence of associated clubfoot, some propose that clubfoot has a neurogenic basis.
3. Primary germ plasm defect or arrested fetal development.
4. Hereditary. There is increased incidence of clubfoot in relatives of affected patients. True clubfoot occurs in one in 2000live birth, and if one has clubfoot, the chance for a subsequent sibling to have it is 20–30 times the baseline incidence.
Clubfoot is not a true subluxation or a dislocation but instead an eõcursion of normal joint motion. Impractical terms, one could hardly improve upon Scarpa’s definition of clubfoot deformity as “twisting of the scaphoid, os calcis, and cuboid around the astragalus”.
Classification of clubfoot:
1. Nonrigid type – positional, perhaps due to intrauterine pacing.
2. Rigid type – true clubfoot:
3. Teratologic type – clubfoot seen with muscle disease, arthrogryposis, spina bifida, and other congenital deformities (teratologyc type).
Patient evaluation. History. Physical examination: The diagnosis of clubfoot is generally easy because the deformity follows the description “talipes equino varus” with the foot fixed in equinus, the heel in varus, and the forefoot supinated.
General examination: Babies with clubfoot require a brief general examination focusing on the spine and hips. The low back should be checked for abnormal skin dimpling that might suggest occult spinal dysraphysm. Because DDH is more common in infants with clubfoot, the hips should be examined.
Foot exam: As previously noted, the foot should be examined to confirm that is fixed in equinus, that the heel is in the varus, and that the forefoot is adducted. The calf is small and the heel is “empty” (heel pad soft to palpation – because the calcaneus is pulled upward by the contracted heel cord). A simple matrix can help pediatricians and family physicians differentiate between the three common foot deformations seen in the neonate: calcaneal valgus, metatarsus varus, and clubfoot. Note that tendo-Achilles contracture occurs only in clubfoot.
X–rays for clubfoot: Forced dorsiflexion anteposterior and lateral x–rays taken at age 3–6 months, help in diagnosis and determining if surgery will be needed to complete the correction. Complex angles can be drawn on the films, and judgments can be made from them. The normal approximate 30° angle between the talus and calcaneus on the anteroposterior view is known as “Kite’s angle”. This angle is increased (approximate 50°) in case of metatarsus varus, and decreased (approximate 5°) in case of clubfoot.
Nonoperative treatment: Strapping, taping or soft-roll application-padding can be used where deformation is slight or where cast correction may be difficult or impossible (premature infant with multiple anomalies, monitored infant in neonatal intensive care unit when feet need to be available for blood draws, etc).
Early in the 20th century, Hoke developed and Kite popularized serial cast correction of clubfoot that produced excellent results. Serial corrective plaster casts, applied initially at weekly intervals, provide the most rapid and effective nonoperative correction of clubfoot. Traditionally, clubfoot casts were applied immediately after birth. Now, in most cases this manipulation performs for 3–5 days, after the child and mother discharged from hospital.
* Technique of the pre-casting manipulative procedure and specific technique for clubfoot cast application will be analyzed in class.
In a typical case, the cast is changed weekly for 4–8 weeks and then biweekly until the 12th week. After 10–12 weeks of cast correction, you will develop a sense of whether the foot can improve with further casts or whether surgical correction might be needed. If further correction seems possible (less likely after 12-week casts), serial casts can be continued for another 4–6 weeks.
When the foot appears corrected, traditionalists apply straight-last shoes plus a bar with the feet externally rotated 45–60°. The shoes plus brace can be worn 23 hours/day for several months, followed by only nighttime wear until about 1 year.
Surgical correction of clubfoot: Early passive manipulative correction and serial corrective casting provides complete correction in a few cases, but only partial correction in most. Partially corrected cases require surfery to obtain complete correction, usually performed at age 6–12 months.
The techniques for revision surgery can be broadly categorized as follows:
1. Disassembly – correction through joints (often very difficult).
2. Osteotomies – correction through bone.
3. Fusion – triple arthrodesis (for mature feet).
4. Tendon transfers – anterior tibial, posterior tibial often as supplement to 2 and 3.
5. Ilizarov method – for particularly complex cases especially if skin, vascular problems anticipated.
Scientific Basis of Management
Our treatment of clubfoot is based on the biology of the deformity and of the functional anatomy of the foot.
Clubfoot is not an embryonic malformation. A normally developing foot turns into a clubfoot during the second trimester of pregnancy. Clubfoot is rarely detected with ultrasonography before the 16th week of gestation. Therefore, like developmental hip dysplasia and idiopathic scoliosis, clubfoot is a developmental deformation.
A 17-week-old male fetus with bilateral clubfoot, more severe on the left, is shown. A section in the frontal plane through the malleoli of the right clubfoot shows the deltoid, tibionavicular ligament, and the tibialis posterior tendon to be very thick and to merge with the short plantar calcaneonavicular ligament. The interosseous talocalcaneal ligament is normal.
A photomicrograph of the tibionavicular ligament shows the collagen fibers to be wavy and densely packed. The cells are very abundant, and many have spherical nuclei (original magnification, x475).
The shape of the tarsal joints is altered relative to the altered positions of the tarsal bones. The forefoot is in some pronation, causing the plantar arch to be more concave (cavus). Increasing flexion of the metatarsal bones is present in a lateromedial direction.
In the clubfoot, there appears to be excessive pull of the tibialis posterior abetted by the gastrosoleus and the long toe flexors. These muscles are smaller in size and shorter than in the normal foot. In the distal end of the gastrosoleus, there is an increase of connective tissue rich in collagen, which tends to spread into the tendo Achillis and the deep fasciae.
In the clubfoot, the ligaments of the posterior and medial aspect of the ankle and tarsal joints are very thick and taut, thereby severely restraining the foot in equinus and the navicular and calcaneus in adduction and inversion. The size of the leg muscles correlates inversely with the severity of the deformity. In the most severe clubfoot, the gastrosoleus is seen as a muscle of small size in the upper third of the calf. Excessive collagen synthesis in the ligaments, tendons, and muscles may persist until the child is 3 or 4 years of age and might be a cause of relapses. Under the microscope, the bundles of collagen fibers display a wavy appearance known as crimp. This crimp allows the ligaments to be stretched. Gentle stretching of the ligaments in the infant causes no harm. The crimp reappears a few days later, allowing for further stretching. That is why manual correction of the deformity is feasible.
The clubfoot deformity occurs mostly in the tarsus. The tarsal bones, which are mostly made of cartilage, are in the most extreme positions of flexion, adduction, and inversion at birth. The talus is in severe plantar flexion, its neck is medially and plantarly deflected, and its head is wedge-shaped. The navicular is severely medially displaced, close to the medial malleolus, and articulates with the medial surface of the head of the talus. The calcaneus is adducted and inverted under the talus.
As shown in a 3-day-old infant [4 opposite page], the navicular is medially displaced and articulates only with the medial aspect of the head of the talus. The cuneiforms are seen to the right of the navicular, and the cuboid is underneath it.
The calcaneocuboid joint is directed posteromedially. The anterior two-thirds of the calcaneus is seen underneath the talus. The tendons of the tibialis anterior, extensor hallucis longus, and extensor digitorum longus are medially displaced. No single axis of motion (like a mitered hinge) exists on which to rotate the tarsus, whether in a normal or a clubfoot. The tarsal joints are functionally interdependent. The movement of each tarsal bone involves simultaneous shifts in the adjacent bones. Joint motions are determined by the curvature of the joint surfaces and by the orientation and structure of the binding ligaments. Each joint has its own specific motion pattern. Therefore, correction of the extreme medial displacement and inversion of the tarsal bones in the clubfoot necessitates a simultaneous gradual lateral shift of the navicular, cuboid, and calcaneus before they can be everted into a neutral position. These displacements are feasible because the taut tarsal ligaments can be gradually stretched.
The correction of the severe displacements of the tarsal bones in clubfoot requires a clear understanding of the functional anatomy of the tarsus. Unfortunately, most orthopaedists treating clubfoot act on the wrong assumption that the subtalar and Chopart joints have a fixed axis of rotation that runs obliquely from anteromedial superior to posterolateral inferior, passing through the sinus tarsi. They believe that
by pronating the foot on this axis, the heel varus and foot supination can be corrected.
This is not so.
Pronating the clubfoot on this imaginary fixed axis tilts the forefoot into further pronation, thereby increasing the cavus and pressing the adducted calcaneus against the talus. The result is a breach in the hindfoot, leaving the heel varus uncorrected.
In the clubfoot, the anterior portion of the calcaneus lies beneath the head of the talus. This position causes varus and equinus deformity of the heel. Attempts to push the calcaneus into eversion without abducting it will press the calcaneus against the talus and will not correct the heel varus. Lateral displacement (abduction) of the calcaneus to its normal relationship with the talus will correct the heel varus deformity of the clubfoot.
Correction of clubfoot is accomplished by abducting the foot in supination while counterpressure is applied over the lateral aspect of the head of the talus to prevent rotation of the talus in the ankle. A well-molded plaster cast maintains the foot in an improved position. The ligaments should never be stretched beyond their natural amount of give. After 5 days, the ligaments can be stretched again to further improve the degree of correction of the deformity. The bones and joints remodel with each cast change because of the inherent properties of young connective tissue, cartilage, and bone, which respond to the changes in the direction of mechanical stimuli. This has been beautifully demonstrated by Pirani , comparing the clinical and magnetic resonance imaging appearance before, during, and at the end of cast treatment. Note the changes in the talonavicular joint and calcaneocuboid joint. Before treatment, the navicular (red outline) is displaced to the medial side of the head of the talus (blue). Note how this relationship normalizes during cast treatment. Similarly, the cuboid (green) becomes aligned with the calcaneus (yellow) during the same cast treatment.
Before applying the last plaster cast, the tendo Achillis may have to be percutaneously sectioned to achieve complete correction of the equinus. The tendo Achillis, unlike the tarsal ligaments that are stretchable, is made of non-stretchable, thick, tight collagen bundles with few cells. The last cast is left in place for 3 weeks while the severed heel-cord tendon regenerates in the proper length with minimal scarring.
At that point, the tarsal joints have remodeled in the corrected positions. In summary, most cases of clubfoot are corrected after five to six cast changes and, in many cases, a tendo Achillis tenotomy. This technique results in feet that are strong, flexible, and plantigrade. Maintenance of function without pain has been demonstrated in a 35-year follow-up study.
Current Ponseti Management Is Ponseti management now accepted as optimal treatment worldwide?
Over the past decade Ponseti management has become accepted throughout the world as the most effective and least expensive treatment of clubfoot. How does Ponseti management correct the deformity?
Keep in mind the basic clubfoot deformity. Compare the normal relationships of the tarsal bones [2 left] with that of the clubfoot [2 right]. Note that the talus (red) is deformed and the navicular (yellow) is medially displaced. The foot is rotated around the head of the talus (blue arrow). Ponseti correction is achieved by reversing this rotation. Correction is achieved gradually by serial casts. The Ponseti
technique corrects the deformity by gradually rotating the foot around the head of the talus (red circle) over a period of weeks during cast correction. When should treatment with Ponseti management be undertaken?
When possible, start soon after birth (7 to 10 days). However, most clubfoot deformities can be corrected throughout childhood using this management. When treatment is started early, how many cast changes are usually required? Most clubfoot deformities can be corrected in approximately 6 weeks by weekly manipulations followed by plaster cast applications. If the deformity is not corrected after six or seven plaster cast changes, the treatment is most likely faulty.
How late can treatment be started and still be helpful? The goal is to start treatment in the first few weeks after birth. However, correction can be achieved in many cases until late childhood. Is Ponseti management useful if treatment is delayed? Management that is delayed until early childhood may be started with Ponseti casts. In some cases, operative correction will be required, but the magnitude of the procedure may be less than would have been necessary without Ponseti management.
What is the expected outcome for the infant with clubfoot treated by Ponseti management?
In all patients with unilateral clubfoot, the affected foot is slightly shorter (mean, 1.3 cm) and narrower (mean, 0.4 cm) than the normal foot. The limb lengths, on the other hand, are the same, but the circumference of the leg on the affected side is smaller (mean, 2.3 cm). The foot should be strong, flexible, and pain free. This correction is expected throughout the person’s lifetime. This provides the opportunity for normal function during childhood and a pain-free and mobile foot during adult life.
What is the incidence of clubfoot in children with one or two parents who also are affected?
When one parent is affected with clubfoot, there is a 3% to 4% chance that the offspring will also be affected. However, when both parents are affected, the offspring have a 30% chance of developing clubfoot. How do the outcomes of surgery and Ponseti management compare? Surgery improves the initial appearance of the foot but does not prevent recurrence. Adult foot and ankle surgeons report that these surgically treated feet become weak, stiff, and often painful in adult life.
How often does Ponseti management fail and operative correction become necessary? The success rate depends on the degree of stiffness of the foot, the experience of the surgeon, and the reliability of the family. In most situations, the success rate can be expected to exceed 95%. Failure is most likely if the foot is stiff with a deep crease on the sole of the foot and above the ankle, severe cavus and small gastrosoleus muscle with fibrosis of the lower half. Is Ponseti management useful for clubfoot in infants with other musculoskeletal problems?
Ponseti management is appropriate for use in children with arthrogryposis, myelomeningocele, Larsen syndrome and other syndromes. Treatment is more difficult as correction takes longer and special care must be given in infants with sensory problems as in myelodysplasia to prevent skin ulcers.
Is Ponseti management useful for clubfoot previously treated by other methods? Ponseti management is also successful when applied to feet that have been manipulated and casted by other practitioners who are not yet skilled in this very exacting management.
What are the usual steps of clubfoot management?
Most clubfoot can be corrected by brief manipulation and then casting in maximum correction. After approximately five casting periods, the cavus, adductus and varus are corrected. A percutaneous heel-cord tenotomy is performed in nearly all feet to complete the correction of the equinus, and the foot is placed in the last cast for 3 weeks. This correction is maintained by night splinting using a foot abduction brace, which is continued until approximately 2 to 4 years of age. Feet treated by this management have been shown to be strong, flexible, and pain free, allowing a normal life.
Making the diagnosis Screening Encourage all healthcare workers to screen all newborns and infants for foot deformities and other problems. Infants with problems can be referred for care at a clubfoot clinic. Confirming The diagnosis suggested during screening is made by someone with experience with musculoskeletal problems who can establish the diagnosis. The essential features of a clubfoot include cavus, varus, adductus and equinus. During this evaluation, other conditions such as metatarsus adductus and the presence of some underlying syndrome can be ruled out. Furthermore, the clubfoot is classified into categories. This classification is made to establish the prognosis and to plan management.
Classifying the clubfoot
The classification of a clubfoot may change with time depending on management.
This is the classic clubfoot and is found in otherwise normal infants. It generally corrects in five casts, and with Ponseti management the long-term oucome is usually good or excellent.
Positional clubfoot Rarely the deformity is very flexible and is thought to be due to intrauterine crowding. Correction is often achieved with one or two castings.
Delayed treated clubfoot beyond 6 months of age.
Recurrent typical clubfoot may occur whether the original treatment was by Ponseti management or other methods. Relapse is much less frequent after Ponseti management and is usually due to a premature discontinuation of bracing. The recurrence is most often supination and equinus that is first dynamic but may become fixed with time.
Alternatively treated typical clubfoot includes feet treated by surgery or non-Ponseti casting.
This category of clubfoot is usually associated with other problems. Start with Ponseti management. Correction usually is more difficult. Rigid or resistant atypical clubfoot may be thin or fat. The fat feet are much more difficult to treat. They are stiff, short, chubby, with a deep crease in the sole of the foot and behind the ankle, and have shortening of the first metatarsal with hyperextension of the metatarsal phalangeal joint. This deformity occurs in the otherwise normal infant. Syndromic clubfoot Other congenital abnormalities are present. The clubfoot is part of a syndrome. Ponseti management remains the standard of care, but may be more difficult, and response may be less predictable. The final outcome may depend more on the underlying condition than the clubfoot.
Teratologic clubfoot – such as congenital tarsal synchondrosis.
Neurogenic clubfoot – associated with a neurological disorder such as
Acquired clubfoot – such as Streeter dysplasia.
Ponseti Cast Correction
The setup for casting includes calming the child with a bottle or breast feeding. When possible have a trained assistant. Sometimes is necessary for the parent to assist. The treatment setup is important. The assistant holds the foot while the manipulator (red dot) performs the correction.
Manipulation and casting
Start as soon after birth as possible. Make the infant and family comfortable. Allow the infant to feed during the manipulation and casting processes. Exactly locate the head of the talus This step is essential. First, palpate the malleoli with the thumb and index finger of hand A while the toes and metatarsals are held with hand B. Next , slide your thumb and index finger of hand A forward to palpate the head of the talus (red outline) in front of the ankle. Because the navicular is medially displaced and its tuberosity is almost in contact with the medial malleolus, you can feel the prominent lateral part of the talar head (red) barely covered by the skin in front of the lateral malleolus. The anterior part of the calcaneus will be felt beneath the talar head. While moving the forefoot laterally in supination, you will be able to feel the navicular move ever so slightly in front of the head of the talus as the calcaneus moves laterally under the talar head.
The manipulation consists of abduction of the foot beneath the stabilized talar head. Locate the head of the talus. All components of clubfoot deformity, except for the ankle equinus, are corrected simultaneously. To gain this correction, you must locate the head of the talus, which is the fulcrum for correction.
Reduce the cavus
The first element of management is correction of the cavus deformity by positioning the forefoot in proper alignment with the hindfoot. The cavus, which is the high medial arch is due to the pronation of the forefoot in relation to the hindfoot. The cavus is always supple in newborns and requires only elevating the first ray of the forefoot to achieve a normal longitudinal arch of the foot. The forefoot is supinated to the extent that visual inspection of the plantar surface of the foot reveals a normal appearing arch—neither too high nor too flat. Alignment of the forefoot with the hindfoot to produce a normal arch is necessary for effective abduction of the foot to correct the adductus and varus.
Steps in cast application
Dr. Ponseti recommends the use of plaster material because it is less expensive and more precisely molded than fiberglass. Preliminary manipulation Before each cast is applied, the foot is manipulated. The heel is not touched to allow the calcaneus to abduct with the foot.
Applying the padding Apply only a thin layer of cast padding to allow molding of the foot. Maintain the foot in the maximum corrected position by holding the toes with counterpressure applied against the head of the talus while the cast is being applied.
Applying the cast First apply the cast below the knee and then extend the cast to the upper thigh. Begin with three to four turns around the toes, and then work proximally up to the knee. Apply the plaster smoothly. Add a little tension to the
turns of plaster above the heel. The foot should be held by the toes and plaster wrapped over the “holder’s” fingers to provide ample space for the toes.
Molding the cast Do not try to force correction with the plaster. Use light pressure.
Do not apply constant pressure with the thumb over the head of the talus; rather, press and release repetitively to avoid pressure sores of the skin. Mold the plaster over the head of the talus while holding the foot in the corrected position. Note that the thumb of the left hand is molding over the talar head while the right hand is molding the forefoot in supination. The arch is well molded to avoid flatfoot or rocker-bottom deformity. The heel is well molded by countering the plaster above
the posterior tuberosity of the calcaneus. The malleoli are well molded. The calcaneus is never touched during the manipulation or casting. Molding should be a dynamic process; constantly move the fingers to avoid excessive pressure over any single site. Continue molding while the plaster hardens. Extend cast to thigh Use much padding at the proximal thigh to avoid skin irritation. The plaster may be layered back and forth over the anterior knee for strength and for avoiding a large amount of plaster in the popliteal fossa area, which makes cast removal more difficult. Trim the cast Leave the plantar plaster to support the toes, and trim the cast dorsally to the metatarsal phalangeal joints, as marked on the cast. Use a plaster knife to remove the dorsal plaster by cutting the center of the plaster first and then the medial and lateral plaster. Leave the dorsum of all the toes free for full extension. Note the appearance of the first cast when completed. The foot is in equinus, and the forefoot is supinated.
Characteristics of adequate abduction
Confirm that the foot is sufficiently abducted to safely bring the foot into 0 to 5 degrees of dorsiflexion before performing tenotomy. The best sign of sufficient abduction is the ability to palpate the anterior process of the calcaneus as it abducts out from beneath the talus. Abduction of approximately 60 degrees in relationship to the frontal plane of the tibia is possible. Neutral or slight valgus of os calcis is present. This is determined by palpating the posterior os calcis.
Remember that this is a three-dimensional deformity and that these deformities are corrected together. The correction is accomplished by abducting the foot under the head of the talus. The foot is never pronated.
The final outcome
At the completion of casting, the foot appears to be over-corrected into abduction with respect to normal foot appearance during walking. This is not in fact an overcorrection. It is actually a full correction of the foot into maximum normal abduction. This correction to complete, normal, and full abduction helps prevent recurrence and does not create an overcorrected or pronated foot.
Complications of Casting
Using careful technique, as described, complications are uncommon. Rocker-bottom deformity is due to poor technique by dorsiflexing the foot too early against a very tight Achilles tendon. Crowded toes are due to tight casting over the toes. Flat heel pad will occur if, while casting, pressure is applied to the heel rather than molding the cast above the ankle. Superficial sores are managed by applying a dressing and a new cast with additional padding. Pressure sores are due to poor technique. Common sites include the head of the talus, over the heel, under the first metatarsal head, and popliteal and groin regions.
Deep sores are dressed and left out of the cast for one week to allow healing. Casting is then resumed with special care to avoid relapse.
Remove each cast in clinic just before a new cast is applied. Avoid cast removal before clinic because considerable correction can be lost from the time the cast is removed until the new one is placed. Options for removal Avoid using a cast saw because it is frightening to the infant and family and may also cause injury to the skin. Cast knife removal Soak the cast in water for about 20 minutes, and then wrap the cast in wet cloths before removal. This can be done by the parents at home just before their visit. Use the plaster knife, and cut obliquely to avoid cutting the skin. Remove the above-knee portion of the cast first. Finally, remove the below-knee portion of the cast. Soaking and unwrapping This is an effective method, but requires more time. Soak cast thoroughly in water and when completely soft unwrap the plaster. To make this process easier, leave the end of the plaster free for identification.
Common Management Errors
Pronation or eversion of the foot This position worsens the deformity by increasing the cavus. Pronation does nothing to abduct the adducted and inverted calcaneus, which remains locked under the talus. It also creates a new deformity of eversion through the mid and forefoot, leading to a beanshaped foot. “Thou shall not pronate!” External rotation of foot to correct adduction while calcaneus remains in varus This causes a posterior displacement of the lateral malleolus by externally rotating the talus in the ankle mortise. This displacement is an iatrogenic deformity.
Avoid this problem by abducting the foot in flexion and slight supination to stretch
the medial tarsal ligaments, with counter-pressure applied on the lateral aspect of the head of the talus [2 thumb position]. This allows the calcaneus to abduct under the talus with correction of the heel varus.
Kite’s method of manipulation
Kite believed that the heel varus would correct simply by everting the calcaneus. He did not realize that the calcaneus can evert only when it is abducted (i.e., laterally rotated) under the talus.
Abducting the foot at the midtarsal joints with the thumb pressing on the lateral side of the foot near the calcaneocuboid joint blocks abduction of the calcaneus and interferes with correction of the heel varus. Make certain the foot is abducted around the head of the talus.
Failure to manipulate The foot should be immobilized with the contracted ligaments at maximum stretch obtained after each manipulation. In the cast, the ligaments loosen, allowing more stretching at the next session.
Short-leg cast The cast must extend to the groin. Short-leg casts do not hold the calcaneus abducted.
Premature equinus correction Attempts to correct the equinus before the heel varus
and foot supination are corrected will result in a rocker-bottom deformity. Equinus
through the subtalar joint can be corrected by calcaneal abduction.
Failure to use appropriate night bracing
Avoid using a short leg brace as it fails to hold the foot in abduction. The external bar brace should be used full time for 3 months and at night for 4 years. Failure of appropriate bracing is the most common cause of relapse. Attempts to obtain perfect anatomical correction It is wrong to assume that early alignment of the displaced skeletal elements will result in normal anatomy. Long-term follow-up radiographs show abnormalities. However, good long-term function of the clubfoot can be expected. There is no correlation between the radiographic appearance of the foot and long-term function.
Indication for tenotomy Tenotomy is indicated to correct equinus when cavus, adductus, and varus are fully corrected but ankle dorsiflexion remains less than 10 degrees above neutral. Make certain that abduction is adequate for performing the tenotomy.
Characteristics of adequate abduction
Confirm that the foot is sufficiently abducted to safely bring the foot into 0 to 5 degrees of dorsiflexion before performing tenotomy. The best sign of sufficient abduction is the ability to palpate the anterior process of the calcaneus as it abducts out from beneath the talus. Abduction of approximately 60 degrees, in relationship to the frontal plane of the tibia is possible. Neutral or slight valgus of os calcis is present. This is determined by palpating the posterior os calcis. Remember that this is a three-dimensional deformity and that these deformities are corrected together. The correction is accomplished by abducting the foot under the head of the talus.
The foot is never pronated.
Preparing the family Prepare the family by explaining the procedure. Explain that tenotomy is a minor procedure performed under local anesthetic in the outpatient clinic. Equipment Prepare all of the material in advance . Select a tenotomy blade, such as a #11 or #15, or any other small blade, such as an ophthalmic knife. Skin preparation Prep the foot thoroughly from midcalf to midfoot with an antiseptic while the assistant holds the foot from the toes with the fingers of one hand and the thigh with the other.
Anesthesia A small amount of local anesthetic may be infiltrated near the tendon. Be aware that too much local anesthetic makes palpation of the tendon difficult and the procedure more complicated.
Setup for the tenotomy
With the assistant holding the foot in maximum dorsiflexion, select a site about 1.5 cm above the calcaneus for the tenotomy. Infiltrate a small amount of local anesthetic just medial to the tendon at the site selected for the tenotomy. Be aware that too much local anesthetic makes palpation of the tendon difficult and the procedure more complicated. Keep in mind the anatomy. The neurovascular bundle is anteromedial to the heel cord. The heel-cord tendon (light blue) lies within the tendon sheath.
Insert the tip of the scalpel blade from the medial side, directed immediately anterior to the tendon. Keep the flat part of the blade parellel to the tendon. The initial entry causes a small longitudinal incision. Care must be taken to be gentle so as not to accidentally make a large skin incision. The tendon sheath is not divided and left intact. The blade is then rotated, so that its sharp edge is directed posteriorly towards the tendon. The blade is then moved a little posteriorly. A “pop” is felt as the sharp edge releases the tendon. The tendon is not cut completely unless a “pop” is appreciated. An additional 15 to 20 degrees of dorsiflexion is typically gained after the tenotomy.
Post-tenotomy cast After correction of equinus by tenotomy, apply the fifth cast with the foot abducted 60 to 70 degrees with respect to the frontal plane of the ankle, and 15 degrees dorsiflexion. The foot looks over-corrected with respect to the thigh. This cast holds the foot for 3 weeks after complete correction. It should be replaced if it softens or becomes soiled before 3 weeks. The baby and mother may go home immediately. Usually no analgesic is necessary. This is usually the last cast required in the treatment program.
After 3 weeks, the cast is removed. Twenty degrees of dorsiflexion is now possible. The tendon is healed. The operative scar is minimal. The foot is ready for bracing [6ww]. The foot appears to be over-corrected into abduction. This is often a concern to the caregiver. Explain that this is not an overcorrection, only full abduction. Errors during tenotomy Premature equinus correction Attempts to correct the equinus before the heel varus and foot supination are corrected will result in a rocker-bottom deformity. Equinus through the subtalar joint can be corrected only if the calcaneus abducts. Tenotomy is indicated after cavus, adductus, and varus are fully corrected. Failure to perform a complete tenotomy The sudden lengthening with a “pop” or “snap” signals a complete tenotomy. Failure to achieve this may indicate an incomplete tenotomy. Repeat the tenotomy maneuver to ensure a complete tenotomy if there is no “pop” or “snap.”
Bracing is essential
At the end of casting, the foot is abducted to an exaggerated amount, which should measure 60 to 70 degrees (thigh-foot axis). After the tenotomy, the final cast is left in place for 3 weeks. Ponseti’s protocol then calls for a brace to maintain the foot in abduction and dorsiflexion. This is a bar attached to straight-last open-toe shoes. This degree of foot abduction is required to maintain the abduction of the calcaneus and forefoot and prevent relapse. The medial soft tissues remain stretched out only if the brace is used after the casting. In the brace, the knees are left free, so the child can kick them “straight” to stretch the gastrosoleus tendon. The abduction of the feet in the brace, combined with the slight bend (convexity away from the child), causes the feet to dorsiflex. This helps maintain the stretch on the gastrocnemius muscle and heel-cord tendon. Ankle-foot orthoses (AFO’s) are not useful because they only keep the foot straight with neutral dorsiflexion.
Three weeks after the tenotomy, the cast is removed and a brace is applied immediately. The brace consists of open-toe hightop straight-last shoes attached to a bar . For unilateral cases, the brace is set at 60 to 70 degrees of external rotation on the clubfoot side and 30 to 40 degrees of external rotation on the normal side . In bilateral cases, it is set at 70 degrees of external rotation on each side. The bar should be of sufficient length so that the heels of the shoes are at shoulder width . A common error is to prescribe too short a bar, that the child finds uncomfortable. A narrow brace is a common reason for a lack of compliance. The bar should be bent 5 to 10 degrees with the convexity away from the child, to hold the feet in dorsiflexion.
The brace should be worn full time (day and night) for the first 3 months after the last cast is removed. After that, the child should wear the brace for 12 hours at night and 2 to 4 hours in the middle of the day, for a total of 14 to 16 hours during each 24-hour period. This protocol continues until the child is 3 to 4 years of age.
Occasionally, a child will develop excessive heel valgus and external tibial torsion while using the brace. In such instances, the physician should reduce the external rotation of the shoes on the bar from approximately 70 degrees to 40 degrees.
Importance of bracing
The Ponseti manipulations combined with the percutaneous tenotomy regularly achieve an excellent result. However, without a diligent follow-up bracing program, relapse occurs in more than 80% of cases. This is in contrast to a relapse rate of only 6% in compliant families (Morcuende et al.).
When to stop bracing
How long should the nighttime bracing protocol continue? As it is often difficult to determine severity, we recommend that all feet should be braced for to 3 to 4 years. Most children get used to the bracing, and it becomes part of their lifestyle. If after 3 years of age compliance becomes a problem, it may become necessary to discontinue the bracing. The child is closely followed for evidence of relapse. Should early relapse be observed, bracing should be promptly started again.
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Congenital muscular tortocollis: Several statues of Alexander the Great show him with his head tilted and rotated to one side – the characteristic of this problem. Read on to discover whether he had torticollis (tort = torsion, colli = neck).
Causes: The first step is a literature search, in the hopes of gathering information. The majority of cases are associated with difficult delivery, particularly breech delivery. There are several interpretations: One theory is that breech children have a contracture producing the malposition and making them liable to torticollis; supporting this theory is an association between torticollis, congenital dislocation of the hip (20%), and metatarsus varus. A second possibility is that obstetrical maneuvers to deliver the aftercoming head damage the muscle by hyperextending and rotating the head (in the 1890s, 5% of breech-birth infants were found to have hemorrhages in the sternomastoid). But the condition has been seen after cesarean section, and several cases have been seen in family. Vertebral anomalies are found it some. Experimental work on stretching and tearing the muscle has been done in animals, but the result is not the same as in children.
A third, more recent theory is that an intrauterine compartment syndrome affecting the sterho-cleido-mastoid- (SCM) compartment produces the torticollis. Most children with torticollis have a history with a difficult delivery, which cause the foots to be delayed in the birth canal, leading to compression of the SCM muscle on the side of the neck. The correlation of the fetal presentation with the side affected was conviencing.
Features: The torticollis is seldom visible at birth. After a week a lump forms at the lower end of the sternomastoid muscle and persists for a month or two. The head is held rotated. A left lump causes the child to look to the right. There is restriction of movement. One result is that the child will always rest on the same part of the head. The same side of the face rests on the crib and becomes flattened by pressure.
A contributory factor may be the size of baby ’s head. Relatively larger than the adult head, the occiput projects posterior to the thorax. Babies have difficulty lying on their back and facing straight ahead. In addition, the muscle shortens.
If the contracture is not corrected at a young age, the facial asymmetry persists. Three emarginary lines may be drown transversally through both eyes both lips and both clavicles of the patient. Usually there is parallelism between these lines. If the face is asymmetrical, these lines are intersected. This is known as positive Wölker sign. Back to Alexander the Great. The statues show no facial asymmetry, and a sculptor following a fashionable trend probably dictated the position – not by torticollis.
Treatment and results: The standard treatment during the first 6 months is a physiotherapy program; stretching the shortened sternomastoid muscle is started by theraputist and taught to the mother. Advice is given about positioning the child’s head in the crib to prevent continued flattering during sleep.
This is effective in most children.
Children Older Than 1 year: Therapy will not be effective in these children. Lengthen or tenotomy of the both ends of the shortened sternomastoid muscle surgically. Lengthening the muscle at both ends is more effective than lengthening at one end. The results are good. Recurrence is rare.
When torticollis is recent onset, there are more possible causes:
1. Inflammation. This is rare – for example: acute calcific deposit in the disc;
juvenile rheumatoid arthritis; pyogenic conditions; or tubercular osteomyelitis.
2. Neurological disorders. Post-fossa tumor.
3. Optical disorders (a squint). Superior oblique palsy is a rare but well
recognized cause of head tilted in children. Some orthopedists go as far as ordering an ophthalmologic consultation before lengthing the SCM muscle surgically.
4. Trauma. A: Rotatory fuxation: A child may wake after tonsillectomy with
his or her head in the forced position. A sore throat is another association, and this is very common event. The head is held in this position and will not straighten. Plain x-rays are hard to interpret because of the twist. Computerized tomography (CT) shows the displacement. When the three joints linking C1 to C2 are rotated beyond their limit, they lock, this is cause of the problem. When it is associated with a sore throat, treat the throat and see recovery of the neck. B: Loced facets. A flexion – injury in a teenager can result in the C5 facet on one side jumping in front of the C6 facet, just as it does in adults. Reduction, closed if possible, relives pain and torticollis.
In conclusion the following points should be noted:
1. Scoliosos, DDH, clubfoot, torticollis in children and adolescents are relatively common problems.
2. These diseases must be recognized and treated early. A careful history and exam (physical examination, x-ray, CT scan, ultrasound etc) always of great importance in making a correct diagnosis.
3. In most cases a cause can be find with subsequent treatment leading to correction or stabilisation of deformity.
4. What should be the basis of calculating results? Reaching goal? What are the goals? The first goal of treatment is to achieve beneficial, positive effects – for example, correction of deformity. The second goal of treatment is that negative effects, such as complications, should be avoided. The third goal of treatment may involve negative, but necessary effects. For example surgical treatment of scoliosis requires fusion of the spine for the operation to be success. The fourth goal of treatment is that it should be cost completive with other methods.
You may think that the main function of a doctor is to diagnose and treat diseases. In fact, preventing diseases is even more important.
1. Dennis R. Wenger and Mercer Rang. Art and Practice of Children’s Orthopaedics/ –Paven Press, Ltd., New York, 1993. – P.138-165; 372-455: 487-494.
2. James J.I. P. Scoliosis. – Baltimore: The Williams & Wilkins Company, 1967.
3. Joanne M. Conroy, B. Hugh Dorman. Anesthesia for orthopedic surgery. – Raven Press, Ltd, New York, 1994. – P. 229-234; 302-307.
4. Ronald McRae, Andrew W.G. Kinninmonth. Orthopaedics and Trauma. – London: Churchill Livingstone, 1997. – P. 102-105.
5. Kazmin A.I., Kon I.I., Belenkiy B. Ye. Scoliosis. – Ìoscow.: Ìeditsina, 1981, 272 p.
6. Ornstein E., Voinea A. Seniotics and Diagnosis in Traumatology and Orthopedics. – Kishinev: Stiinta, 1992. – P. 102–106.
7. Volkov M.V., Dedova V.D. Chilgren’s orthopedics. –, 1980. – P. 31-58; 107-120; 133-167
8. Volkov M.V., Ter-Egiazarov G.M.Chilgren’s orthopedics and traumatology. – Ìoscow.: Ìeditsina, 1983. – P. 87-111; 159-176.
9. Yumashev G.S. Traumatology and Orthopedics.– Ìoscow.: Ìeditsina, 1983. – P. 477-486; 529-534.
Scoliosis is a lateral and rotational deformity of the spinal column that has been associated with many disease processes. Hippocrates noted that the scoliotis deformity of the thoracic spine affected the chest wall and, when severe enough, led to respiratory failure. Early treatment of scoliosis consisted of forced horizontal traction and underarm and leg distraction.
The diagnosis and treatment of scoliosis has changed dramatically since the time Hippocrates. In the last 30 years, improvement in surgical techniques has allowed more complex procedures to be performed to stop the progression of spinal curvature and to improve the deformity caused by scoliosis.
Incidence: The incidence of scoliosis reported in the literature varies from 0.3 to 4 per 1000. The female-to-male ratio is approximately 9:1. Idiopathic scoliosis is the most common form of scoliosis and has a strong hereditary disposition. Onset is categorized into three peak periods: infancy (between birth and 3 years); juvenile (between 4 and 10 years), and adolescence (between 10 years and skeletal maturity).
Etiology: Sixty-five percent of scoliosis is idiopathic. Most cases present during periods of maximum growth. This rapid growth occurs just prior to puberty in males and menarche in females, as well as during periods of endocrine hyperactivity, when there is increased protein synthesis and collagen production.
The remaining 35% of scoliosis cases are secondary to congenital and acquired disease processes. The development of the spinal cord, heart and great vessels, and the genitourinary systems are closely related. Scoliosis is frequently associated with defects in these other systems.
Forms of scoliosis: Among the many classifications the following should be noted (J. Cobb, 1958). It includes the following scoliosis:
1. Idiopathic scoliosis;
2. Neurogenic scoliosis;
3. Myopathic scoliosis;
4. Congenital scoliosis;
5. Scoliosis associated with diseases or trauma of the thorax.
Scoliosis is classified as structural and nonstructural. Nonstructural scoliosis is a lateral curvature of the spine without associated defects in the vertebrae or discs. The curve is flexible and corrects by bending the convex side of the curve. This form of scoliosis is usually nonprogressive.
Four main features characterize structural scoliosis: (1) The curve does not straighten with bending. (2) Soft tissue contracts in the concavity of the curve. (3) Structural abnormalities occur, such as wedging of the vertebral bodies and variations in the sizes of the laminae, pedicles, and transverse processes of the individual vertebrae in the deformity. (4) A fixed rotary deformity develops in the vertebral bodies, usually in the direction of the curve.
Respiratory and cardiovascular impairment: Pulmonary function is altered with curvature and chest wall abnormalities. The degree of dysfunction is related in many factors, including type and såverity of curve, age of patient, and associated disease processes. The most common abnormalities associated with scoliosis include: restrictive ventilatory pattern, altered lung volumes, ventilation/perfusion defects, and changes in the pulmonary vasculature that can lead to chronic hypoxia and pulmonary hypertension. Pulmonary function is more significantly impaired with paralytic than with idiopathic scoliosis. Cardiac disease has long been associated with scoliosis. Autopsies of patients with scoliosis reveal right ventricular hypertrophy in 82% of 197 autopsies in patient with kyphoscoliosis. Chronic respiratory insufficiency ultimately affects the cardiovascular system.
History and physical exam: History talking includes inquiry regarding family history of scoliosis, presence or history of skin lesions (neurofibromatosis), history of neuromuscular conditions, and inquiry regarding bowel and bladder function. Examination includes a brief general exam and neurologic exam. After the brief general examination we examine the spine. To understand the patient’s deformity carefully inspect the trunk and back, looking for overall head and trunk balance; this should include assessment of the spine and attached ribs in three dimensions.
Finding scoliosis: The concept of examining children as a public health measure began in England in the late 1800s, becoming common in the early 20th century. Spinal screening involves having a child bend toward, looking for a rotatory prominence of the spine, a test first defined by Adams in London in 1882 [Figure 12]. Because the scoliotic spine rotates with forward bend, and the ribs are attached to the rotated vertebrae, the result is trunk rotation. Screening assessment for scoliosis also includes shoulder height, pelvic asymmetry, and scapular and flank asymmetry [Figure 13]. In some cases skin markers are required in order to obtain an accurate image in the standing position. Repopularization of the Scoliometer has been of greet help in quantifying of trunk rotation. If the trunk is rotated more than 5–7°, the child is referred for x-ray.
X-ray views: Children with spinal asymmetry who need x-ray clarification should have a simple standing posterioanterior view of the spine. Lateral views are not usually ordered as a part of the initial screening x-ray study but should be considered if the child has a lumbar curve or low backache (to rule out spondylolysis/spondylolisthesis). The vast majority of scoliotic patients develop multiple curves, divided into two types: (i) structural curve (major angle), which is defined as the length of the spinal column over which the fixed deformity extends (this is usually the largest curve and is most often to the right) and (ii) compensatory curve (minor angle), which is formed in an attempt to maintain an upright posture. These curves are above and below the structural curve, are not as severe as the major angle curve, and are in the opposite direction. Obtaining spinal roentgenograms in a serial fashion does monitoring the progression or correction of the spinal curvature. The curves are measured by the Cobb method, introduced in 1948. The Cobb angle gives an accurate assessment of the spinal deformity by measuring the angle subtended by the intersecting lines drawn perpendicular to the superior surface of the uppermost vertebrae and the inferior surface of the lowermost vertebrae involved in the major angle.
q Curves less than 20–25 degrees may be observed.
q Those curves progressing beyond 25 degrees will be braced in an attempt to halt the curve progression. Progression of the curve is hopefully arrested or improved after several years of bracing.
q If the curve reached 50–60 degrees, surgical instrumentation should be performed. Internal fixation of the spine is used for reduction of the rib hump, correction of rotation, and achievement of rigid fixation to obtain a solid fusion and stability.
Exercise: Combinations of exercise, physical therapy, and a variety of exercise programs and /or special exercise machines have been used since antiquity. Organized, structured physical therapy remains a common method of scoliosis treatment in many parts of the world. However, a controlled study [Stone ET al., 1979] of the effectiveness of exercise in adolescents with minor scoliosis is found that treated patients fared no better than untreated patients.
Cast treatment: The history of brace treatment includes a variety of plaster casts, as well as metal and leather corrective jackets which developed both in Europe and in the United States. The physical and psychological burden of wearing such a cast for months (and even years) explains the gradual 20th-century evolution to a point where eventually casts were no longer needed to treat scoliosis.
Brace (orthotic) treatment: The objective of brace treatment is to prevent scoliosis progression because braces have not been proven to truly improve the curve. Braces are used most commonly in moderate curves to prevent scoliosis progression, in hope of avoiding corrective surgery. Occasionally they are used for more severe curves in juvenile-age patients, in hope of delaying surgery until the child has grown larger. Blount and Schmidt of Milwaukee introduced the modern era of scoliosis bracing in the 1950s. The Milwaukee brace, designed to be worn 23 hours a day and removed only for bathing and skin are. In the mild-1970s the Boston Children’s Hospital orthopaedic group introduced a new underarm plastic scoliotic brace. The underarm brace style, worn under closing and not visible to the causal observer. Development of the Charleston nighttime bending brace in the late 1980s further advanced the concept of part-time brace wear. Worn only at night while supine, the brace is designed to nearly straighten or, in flexible curves, even reverse the scoliotic curve.
The Risser sign* is widely used in determining when bracing for scoliosis can be determined or when the treating surgeon no longer has to worry about scoliosis curve progression.
* The Risser sign (grading the appearance of the secondary ossification center of the iliac crest apophysis to determine skeletal maturity). Broadly interpreted, when the apophysis has completed its excursion, spinal growth is nearing completion.
Surgical treatment: Hibbs reported Fusion of the spine in 1924. Fusion can be performed anteriorly or posteriorly, although the posterior approach is used most often. Harrington introduced spinal instrumentation in 1962. A midline posterior incision is used to retract the paraspinal muscles and expose the laminae of the vertebrae. After the Harrington rods are fitted to produce spinal correction by longitudinal distraction, the laminae and facet joint are decorticated and fused with bone graft. Postoperatively, the patients are immobilized in plaster cast to allow for solid fusion. In 1982 Luque offered a new technique of segmental vertebral instrumentation, using sublaminar wires. This technique distributes the force of distraction over the length of the fusion, affords earlier stability, and does not require postoperative immobilization. A new segmental spinal instrumentation system has been introduced that allow correction of spinal deformities without sublaminar wiring. The Cotrel–Dubousset instrumentation system also allows for early mobilization and does not require postoperative casting or bracing. The Zielke instrumentation system is currently being used for anterior manipulation of the spinal column for rigid, mobile lumbar, or thoracolumbar scoliosis with lordosis.
Many children and teenagers have postural abnormalities.
There are following main types of the postural abnormalities:
1. Habit Scoliosis (a lateral deformity of the spine column, spinal kyphosis and lordosis are normal).
2. Roundback Deformity (increased thoracic kyphosis) includes not only rounded thoracic spine but also rounded shoulders, increased lordosis (goose neck), anterior pelvic tilt.
3. Swayback (the spinal kyphosis and lordosis are increased, the head is bended toward)þ
4. Flatback (the spinal kyphosis and lordosis are decreased, the neck is elongated, the spine is flexible, anterior pelvic tilt is increased).
Classically, children with a history of poor posture present in juvenile or adolescence period (i.e. between the ages of 10 and 15 years). These forms of posture are initially flexible and may be corrected easily. In the late juvenile period, certain children who are initially flexible begin to lose spine flexibility and develop hamstring tightness. That is why the clinical exam should include a test for flexibility (can they passively correct the deformation?) and a test of hamstring tightness (inches lacking in attempting to reach the floor with forward bend). Standing X–rays should be required in some cases.
Treatment of poor posture: The task includes observation and therapy programs. The patient is referred to a physical therapist. At first the doctor discuss with the patient what his daily lifestyle is, and together they agree on a time when a brief period of exercise would be practical. The most valuable postural alignment exercise is the exercise, providing axial extension of the spine. Instruction is given in stretching exercises for the muscles that are usually tight in a person with poor posture: neck extensors, pectorals, and hamstrings. These exercises are applied together to conservative methods of rehabilitation (physiotherapy, massage, and general therapy).
Idiopathic scoliosis is the most common type of spinal deformity confronting orthopedic surgeons. Its onset can be rather insidious, its progression relentless, and its end results deadly. Proper recognition and treatment of idiopathic scoliosis help to optimize patient outcomes. Once the disease is recognized, effective ways exist to treat it.
Asher et al performed a retrospective study to determine implant/fusion survivorship without reoperation and the risk factors influencing such survival in 207 patients. Of the 207 patients followed, 19 (9.2%) required reoperation, with 16 of those being for indications related to posterior spine instrumentation. Survival of the implant/fusion without reoperation for spine instrumentation-related indications was 96% at 5 years, 91.6% at 10 years, 87.1% at 15 years, and 73.7% at 16 years. The need for reoperation was significantly influenced by 2 implant variables: transverse connector design and the lower instrumented vertebra anchors used.
Luhman et al reviewed the prevalence of and indications for reoperations in 1057 spinal fusions for idiopathic scoliosis. Of the 1057 fusions, 41 (3.9%) required reoperation: 11 anterior, 25 posterior, and 5 circumferential. In addition, 47 other procedures were needed: 20 revision spinal fusions (for pseudarthroses, uninstrumented curve progression, or junctional kyphosis); 16 because of infections (5 acute, 11 chronic); 7 for implant removal because of pain and/or prominence (4 complete, 3 partial); 2 (4%) revisions for loosened implants; and 2 elective thoracoplasties.
Yaszay et al measured the effects of different surgical approaches for adolescent idiopathic scoliosis on pulmonary function over a 2-year period in 61 patients. They evaluated the patients for vital capacity (VC) and peak flow (PF) before surgery and after surgery at 1, 3, 6, 12, and 24 months. They found that scoliosis approaches that penetrated the chest wall resulted in a significant decline in postoperative pulmonary function. Return of pulmonary function did not occur until 3 months after posterior fusion with thoracoplasty; until 3 months after open anterior fusion; and until 1 year after video-assisted thoracoscopic surgery.
After a 10-year follow-up, the data from another study noted that patients who experienced intraoperative chest wall violation during their spinal fusion demonstrated a significant decrease in percent-predicted forced VC and forced expiratory volume in 1 second (FEV1) values. However, those who underwent posterior-only procedures showed significant improvements in forced VC and FEV1absolute values without any change in percent-predicted values; no changes were noted in percent-predicted values at 5 and 10 years in either group. These results suggest that procedures sparing the chest wall may result in better long-term pulmonary function.
Regarding possible prognostication related to curve progression, Wei-Jun et al suggest that body weight in adolescent males may be an important parameter. Abnormal pubertal growth was noted in idiopathic scoliosis patients compared with healthy controls, with longitudinal growth being similar but body weight being significantly lower in the male adolescent scoliosis subjects.
History of the Procedure
Scoliosis is an ancient disease that remains incompletely understood despite a collective medical experience that approaches 4000 years. This is a sad commentary on the learning curve of medical practitioners. Nevertheless, the history of the recognition and treatment of scoliosis is rich with important lessons for the modern practitioner.
Ancient Hindu religious literature (circa 3500-1800 BC) describes the treatment of spinal deformity rather clearly. The story is told of a woman who was "deformed in three places" and how Lord Krishna straightened her back. This was accomplished by pressing down on her feet and pulling up on her chin. The orthopedic trappings of the story are unmistakable, including excellent immediate posttreatment results and no long-term follow-up.
Hippocrates (circa 400 BC) stated, "there are many varieties of curvature of the spine even in persons who are in good health; for it takes place from natural conformation and from habit." He also stated that "lateral curvatures also occur, the proximate cause of which is the attitudes in which these patients lie." The postural and muscular theory of scoliosis thus stated has persisted for thousands of years and remains firmly embraced by some.
Hippocratic scoliosis treatment methods focused primarily on spinal manipulation and traction. He used an elaborate traction table called the scamnum. Medical practitioners used slight variations of the Hippocratic scamnum well into the 1500s. Another treatment approach that Hippocrates discussed involved attempting to diminish spinal deformity with a method called succussion. This involved strapping the patient (often upside down) to a ladder, which was then hoisted into the air and dropped from a height. Hippocrates thought that this method was occasionally useful, but it was largely performed by charlatans to impress the public.
Ambroise Pare has been described as the "most celebrated surgeon of the Renaissance." Pare is recognized as the first physician to treat scoliosis with a brace. He also recognized that once a patient with scoliosis had reached maturity, bracing was not useful. Pare's orthosis consisted of a metal corset (fashioned in a village smithy setting) with many holes in it to help diminish its significant weight. The record also makes it quite clear that Ambroise Pare espoused the postural theory of scoliosis.
Nicholas Andry was a French pediatrician who hated the brutal barber surgeons of his day.. At the age of 83 (a year before his death) he wrote a short book entitled Orthopaedia. Thus, in 1741 this name combined the root words for straight (orthos) and child (paedia) to create the name still used for the broad musculoskeletal field, orthopedics.
Andry believed that scoliosis was caused by asymmetric muscle tightness and, thus, helped foster the French belief in "convulsive muscular contraction" as the cause of spinal deformity. Andry stated, "It is well worth while to remark that the crookedness of the spine does not always proceed from a fault of the spine itself, but is sometimes owing to muscles of the forepart of the body being too short, whereby the spine is rendered crooked, just in the same manner as a bow is made more crooked by tying its cord tighter. Andry used rest, suspension, postural approaches, and padded corsets in his treatment of scoliosis.
Jacques Mathieu Delpech was a successful and skilled surgeon, yet he focused a great deal of his attention on nonsurgical approaches to orthopedic problems. The highlight of this focus was his orthopedic institute at Montpellier, in the south of France. This facility included elaborate gardens, a heated winter gymnasium, and an outdoor gymnasium for the treatment of various musculoskeletal problems.
For the treatment of scoliosis, Delpech devised graded exercises for strengthening muscles of the trunk in the belief that the deformity was due to a weak axial musculature. This belief was almost certainly due to the influence of Andry. Delpech also used stretching and traction techniques but did not believe in braces. His patients usually stayed for 1 or 2 years at the institute, and they would wear uniforms while they performed their exercises. Similar elaborate efforts to treat scoliosis still exist in the physical therapy outpatient setting. Delpech's life and that of his institute came to an abrupt end in 1832 when a disgruntled patient shot him to death as he was riding back to Montpellier in an open carriage.
An important event of the 1800s was the advent of surgical treatment of scoliosis by the French orthopedic surgeon Jules Guerin. He was very enthusiastic about subcutaneous tenotomy and myotomy and first reported their use in his patients with scoliosis in 1839. When he later published the results of treatment of 1,349 patients with this technique, tremendous controversy was ignited. Guerin's harshest critic was Joseph Malgaigne, who described Guerin's work as "some orthopedic illusion." This led to one of the most famous orthopedic lawsuits in history: Guerin versus Malgaigne. This defamation trial ended in Malgaigne's favor and helped to establish an important precedent for open criticism of scientific papers.
Another important tool in the treatment of scoliosis was the plaster body jacket (ie, body cast). The American orthopedic surgeon Lewis Sayre popularized its use in the mid 1800s. Sayre's technique involved a large tripod that allowed the patient to be suspended while the corrective plaster cast was applied. Sayre was said to be "a brusque, forceful and therefore controversial personality" but also "an eloquent speaker" who toured internationally demonstrating his casting techniques. He also used a "jury mast" extension from some of his casts in order to provide constant head traction—a clear predecessor to halo traction.
The early 1900s saw what is arguably the most important advance in scoliosis treatment in more than 3000 years: posterior spinal fusion. Russell Hibbs first performed his "fusion operation" for tuberculous spinal deformity in 1911, but by 1914 he also was applying his technique to patients with scoliosis. The Hibbs approach focused on achieving maximum deformity correction via a variety of plaster jackets before surgery. Hibbs's 1924 description of his own technique is eloquent, as follows:
The dissection is carried farther and farther forward upon each vertebra in turn, until the spinous processes, the posterior surfaces of the laminae, and the base of the transverse processes are bared...[and] with a bone gouge, a substantial piece of bone is elevated from the adjacent edges of each lamina, of half its thickness and of half its width. The free end of the piece from above is turned down to make contact with the lamina below, and the free end of the piece from the lamina below is turned up to make contact with the lamina above...Each spinous process is then partially divided with bone forceps and broken down, forcing the tip to come into contact with the bare bone of the vertebra below.
In the postoperative period, Hibbs typically allowed 2 weeks of bedrest for wound healing, followed by a final traction plaster jacket. The patient would continue to be confined to bed while wearing the corrective cast for another 6 weeks. Following this, the patient would wear a removable brace during the day for an additional 6-12 months. It was clear to Hibbs that with his technique, he could at least partially correct and, more important than this, prevent progression of the curves he was treating.
By 1941, such spinal fusion operations for idiopathic scoliosis were common enough that Shands (of the Alfred I duPont Institute) and his fellow researchers could assess more than 400 cases. Hibbs-type fusion procedures were performed in all cases, but most surgeons (60%) used supplemental bone graft (often from the tibia). An approximately 25% final curve correction was achieved, and an overall 28% pseudarthrosis rate was noted. It would be another 20 years before Paul Harrington would introduce the spinal instrumentation system that would further refine scoliosis surgery. Although Harrington's original concept was instrumentation without fusion, persons such as John Moe would convince him of the value of spinal fusion in concert with Harrington rods.
Further refinement in surgical technique and instrumentation has led to the greater than 50% correction and single-digit pseudarthrosis rates to which contemporary orthopedists have become accustomed.
Scoliosis represents a disturbance of an otherwise well-organized 25-member intercalated series of spinal segments. It is, at times, grossly oversimplified as mere lateral deviation of the spine, when in reality, it is a complex 3-dimensional deformity. In fact, some have used the term rotoscoliosis to help emphasize this very point. Two-dimensional imaging systems (plain radiographs) remain somewhat limiting, and scoliosis is commonly defined as greater than 10° of lateral deviation of the spine from its central axis.
In the past, terminology such as kyphoscoliosis was inappropriately used to describe certain patients with idiopathic scoliosis. Idiopathic scoliosis has a strong tendency to flatten the normal kyphosis of the thoracic spine. Robert Winter teaches that idiopathic scoliosis is a hypokyphotic disease. In most cases, diagnoses of kyphoscoliosis were clinical misinterpretations of the rib hump associated with an otherwise hypokyphotic thoracic spine. Idiopathic scoliosis may present as a true kyphoscoliosis, but this occurs relatively rarely.
J.I.P. James is credited with classifying idiopathic scoliosis according to the age of the patient at the time of diagnosis. Using his classification system, children diagnosed when they are younger than 3 years have infantile idiopathic scoliosis. Children diagnosed when they are aged 3-10 years have juvenile idiopathic scoliosis, and those older than 10 years have adolescent idiopathic scoliosis. These age distinctions, though seemingly arbitrary, have prognostic significance. For instance, Robinson and McMaster reviewed 109 patients with juvenile idiopathic scoliosis and found that nearly 90% of curves progressed, and almost 70% of these patients went on to require surgery. These rates are much higher than the rates associated with other categories of idiopathic scoliosis. The real challenge is to predict which curves will progress significantly and which ones will not. This is discussed in greater detail later in this article.
Scoliosis is almost always discussed in terms of its prevalence (ie, the total number of existing cases within a defined population at risk). Rates may vary quite significantly based on what particular definition of scoliosis is used and what patient population is being studied. Several important studies are included below.
Stirling and his coauthors studied almost 16,000 patients aged 6-14 years in England and found the point prevalence of idiopathic scoliosis (Cobb angle >10°) to be 0.5% (76 of 15,799 patients). The prevalence of scoliosis was highest (1.2%) in patients aged 12-14 years. Data such as these have helped reiterate the idea that the focus of screening efforts should be on children in this age group. When smaller Cobb angle measurements have been accepted (eg, 6° or greater), a significantly higher scoliotic rate may be identified, such as the 4.5% rate reported by Rogala et al. Other studies using the 10° definition of scoliosis have placed the overall prevalence in the 1.9-3.0% range.
Scoliosis has been suggested to develop more frequently in children born to mothers who are aged 27 years or older. One might hypothesize that gene fragility might be involved (eg, higher rate of infants with Down syndrome born to older mothers). The precise explanation as to why this might be the case has not been elucidated. In addition to this, no other authors have duplicated these results.
As mentioned previously, most patients with idiopathic scoliosis are female, and the vast majority of research has focused on females. One of the only articles written on idiopathic scoliosis in males is that by Karol et al, from the Texas Scottish Rite Hospital. These authors showed that boys with scoliosis are at risk for curve progression for a longer period than girls. They also suggested that efforts to screen for boys with scoliosis should be performed a little later than similar screenings for girls.
The precise etiology of idiopathic scoliosis remains unknown, but several intriguing research avenues exist.
A primary muscle disorder has been postulated as a possible etiology of idiopathic scoliosis. The contractile proteins of platelets resemble those of skeletal muscle, and calmodulin is an important mediator of calcium-induced contractility. Kindsfater and his colleagues from Denver studied the level of platelet calmodulin in 27 patients with adolescent idiopathic scoliosis. Using indirect measurement methods, these researchers had conducted previous work indicating that increased levels of platelet calmodulin were associated with increasingly severe idiopathic scoliosis. Using a direct measurement technique, they showed that patients with a progressive curve (>10° progression) had statistically higher platelet calmodulin levels (3.83 ng/mcg vs 0.60 ng/mcg, P < .01). If these data are reproduced in larger studies, they hold the potential to allow clinicians to identify patients at higher risk of curve progression.
An elastic fiber system defect (abnormal fibrillin metabolism) has been offered as one potential etiologic explanation for idiopathic scoliosis. Such abnormal connective tissue has not been found universally in patients with idiopathic scoliosis. No clear cause-and-effect relationship has been established. Further research in this area is clearly warranted.
Disorganized skeletal growth, probably with its root cause at a gene locus or group of loci, has been discussed as a possible etiologic explanation for idiopathic scoliosis. This theory is simply that a rather localized primary growth dysplasia leads to a cascading Hueter-Volkmann effect on a much larger portion of the spine. The Hueter-Volkmann principle states that compressive forces tend to stunt skeletal growth and that distractive forces tend to accelerate skeletal growth. A possible, yet unproven, association with such a growth disturbance is the osteopenia that has been identified in patients with idiopathic scoliosis.
David Aronsson has conducted a series of experiments that have explored this mechanical modulation of growth. Using two different animal models (rats and calves), he showed that the force exerted by external ring fixators were quite capable of producing vertebral segment wedging akin to that seen in human idiopathic scoliosis. Correlation of his laboratory information with the clinical setting has drawn attention to the fact that wedging occurs both from the vertebral bodies themselves and from the disk spaces, with a greater amount of thoracic wedging coming from the vertebral bodies. The asymmetric mechanical forces have also been associated with elevated synthetic activity in the convex side of scoliotic curves.
Bylski-Austrow and Wall led a group of Cincinnati Children's Hospital researchers who further analyzed the mechanical modulation of spinal growth. Using a porcine model, they successfully induced growth changes by means of an endoscopically implanted spinal staple. Within the context of 8 weeks' follow-up, they were able to create 35-40° of scoliotic curvature in growing pigs. Histologic analysis of vertebral specimens revealed increased paraphyseal density and disorganized chondrocyte development in the region of the staple blades.
Genetic roots of the disease referred to as idiopathic scoliosis have been rather strongly suggested by several avenues of research. An X-linked inheritance pattern (with variable penetrance and heterogeneity) has been suggested by several authors. Studies of twins with scoliosis have pointed in a similar direction.. More than 90% of monozygotic twins and more than 60% of dizygotic twins demonstrate concordance regarding their idiopathic scoliosis. Some evidence has also directed attention to portions of chromosomes 6, 10, and 18 as possible scoliosis-related loci.
Much has been written regarding the potential influence of melatonin on the development of idiopathic scoliosis. This has largely originated from studies in which the pineal gland was removed in chickens and scoliosis developed. These same studies suggested that the melatonin deficiency following pinealectomy might be the underlying reason for the development of scoliosis. Bagnall and his coauthors studied pinealectomized chickens to which they administered therapeutic doses of melatonin. They were unable to demonstrate any ability of the melatonin to prevent the development of scoliosis. It is fair to say that no final answer is yet available.
Some authors have suggested that a posterior column lesion within the central nervous system might be present in patients who have idiopathic scoliosis. Such central nervous system dysfunction was hypothesized to be manifested as decreased vibratory sensation. McInnes and her fellow researchers later pointed out that the vibration device used in earlier studies (a Bio-Thesiometer) did not demonstrate sufficient reliability characteristics to allow valid conclusions. This line of research might be attractive to those who feel that a postural disturbance is the root cause of scoliosis.
The vast majority of patients initially present due to perceived deformity. This may be patient or family perception of asymmetry about the shoulders, waist, or rib cage. A primary care physician or school-screening nurse may perceive similar findings. Adams forward-bending test (in conjunction with the use of a scoliometer) has been found to be an effective screening tool.
Highlights of the patient's history include information relative to other family members with spinal deformity, assessment of physiologic maturity (eg, menarche), and presence or absence of pain.
Traditionally, scoliosis has been described as a nonpainful condition, and aggressive workup has been recommended for patients in whom this rule is violated. Ramirez and his coworkers from the Texas Scottish Rite Hospital studied more than 2400 patients with scoliosis and found that a full 23% (560 of 2442 patients) had back pain at the time of presentation. An underlying pathologic condition was identified in 9% (48 of 560) of the patients with back pain, including mainly spondylolysis and spondylolisthesis but also intraspinal tumor in one instance. Thus, it would seem that pain is not associated with scoliosis as rarely as previously thought.
Physical examination should include a baseline assessment of posture and body contour. Shoulder unleveling and protruding scapulae are common. In the most common curve pattern (right thoracic), the right shoulder is consistently rotated forward and the medial border of the right scapula protrudes posteriorly. Assessment of lower (and often upper) extremity reflexes should be performed. Abdominal reflex patterns should also be assessed. The presence or absence of hamstring tightness should be investigated, and screening should be performed for ataxia and/or poor balance or proprioception (ie, Romberg test). One or two different methods of measuring leg length will prove valuable, as a significant percentage of patients presenting with scoliosis have several centimeters of limb-length discrepancy.
An extensive yet incomplete understanding of the natural history of idiopathic scoliosis remains a reality. Thus, more than a modicum of uncertainty remains associated with selection of recommended treatments for idiopathic scoliosis. The main treatment options for idiopathic scoliosis may be summarized as "the 3 O's": (1) observation, (2) orthosis, and (3) operative intervention. When to choose each of these treatments is a complicated matter.
The risk of curve progression varies based on the idiopathic scoliosis group in which a patient belongs (ie, infantile, juvenile, adolescent).
Infantile idiopathic scoliosis
Although defined by a seemingly arbitrary age limit (< 3 y at the time of diagnosis), infantile idiopathic scoliosis demonstrates marked differences that distinguish it from the other 2 categories of idiopathic scoliosis. Infantile idiopathic scoliosis is the only type of idiopathic scoliosis whose most common curve pattern is left thoracic. Infantile idiopathic scoliosis is the only type of scoliosis that is more common in boys. It is more common in European patients or those of immediate European descent. In the past, infantile idiopathic scoliosis may have constituted up to 41% of all idiopathic scoliosis cases in parts of Europe, but the rate would appear to be closer to 4%. This is still dramatically higher than the estimated 0.5% rate in North America.
Infantile idiopathic scoliosis is also the only type of idiopathic scoliosis with any significant reputation for spontaneous resolution. Reported spontaneous resolution rates range from 20-92%. Ceballos et al studied 113 Spanish patients with infantile idiopathic scoliosis. They found a 92% rate of associated plagiocephaly and an almost 25% rate of congenital hip dysplasia. These same researchers found that nearly 74% of their patients' curves were of the resolving variety (mainly left thoracic curves) and the other 26% were progressive curves (mainly double primary type curves).
Prediction of curve progression in infantile idiopathic scoliosis has been tied to assessment of the rib vertebral angle difference (RVAD) originally described by Mehta in 1972. As described by Mehta, this measurement is carried out at the apical vertebra of the curve. In instances in which the curves resolved spontaneously, the RVAD was less than 20° in about 80% of cases, and in those instances in which the curves were progressive, the RVAD exceeded 20° in about 80% of cases. Other authors have confirmed the prognostic value of the RVAD, as well as its reliable application.
Nonoperative treatment of progressive infantile idiopathic scoliosis predominates and may involve the use of conventional thoracolumbosacral orthosis (TLSO)–type braces, Milwaukee-type braces, and even intermittent Risser casting. Some have questioned the value of bracing in infantile idiopathic scoliosis and have stated, "a curve that resolves in a brace would probably have resolved without treatment."
If surgical treatment becomes necessary, anterior release and fusion followed by posterior spinal fusion with instrumentation is considered to be the functional treatment. Every effort should be made to delay such surgical intervention as long as possible to optimize spinal growth, but relentless curve progression should not be accepted or tolerated while awaiting some arbitrary chronologic age. Although intuitively attractive, convex spinal epiphysiodesis (which has been shown to be quite effective in the management of congenital scoliosis) has not been shown to be as reliable in the setting of infantile idiopathic scoliosis. Addition of some type of posterior instrumentation may improve the results of epiphysiodesis.
A treatment outline for infantile idiopathic scoliosis may be as follows:
Curves less than 25° with an RVAD less than 20° are preferentially observed and monitored with spinal radiographs at regular intervals.
Curves exceeding these parameters are typically braced, with some consideration given to the value of intermittent Risser casting.
Surgery is considered for curves not adequately controlled with nonoperative measures.
Juvenile idiopathic scoliosis
Juvenile idiopathic scoliosis most closely mimics the epidemiology and demographics of the adolescent version of the disease. It is more common in females, and its most common curve pattern is a right thoracic curve. In fact, due to its demographic similarities, high rate of progression, and need for surgery, juvenile idiopathic scoliosis might be considered to be a malignant subtype of adolescent idiopathic scoliosis. Robinson and McMaster studied 109 patients with juvenile idiopathic scoliosis in Scotland and found that 95% (104 of 109 patients) demonstrated curve progression and 64% (70 of 109 patients) progressed to require a spinal fusion. This spinal fusion rate is similar to that reported by J.I.P. James 15 years earlier.
A study from Washington University found a 50% rate of neural axis abnormalities in young children (< 10 y) with idiopathic scoliosis. These findings included Chiari type I malformations and dural ectasia. At least one case report also exists in which a spinal intraosseous arteriovenous malformation was found in association with juvenile scoliosis.
One potential treatment algorithm for juvenile idiopathic scoliosis is as follows:
Observation for curves less than 25° with follow-up radiographs at regular intervals
Bracing for curves that range from 25-40° and at least consideration of bracing (based on curve flexibility) for curves from 40-50°
Bracing for smaller curves that demonstrate rapid progression to the 20-25° range
Surgical intervention for inflexible curves that exceed 40° or virtually any curve that exceeds 50°.
Bracing and casting may be used outside the above-mentioned parameters in an effort to help control a large curve in a young child for whom the surgeon is attempting to optimize spinal growth. Similar recommendations exist regarding the value of MRI in juvenile idiopathic scoliosis due to a significant rate of neural axis abnormalities.
Adolescent idiopathic scoliosis
Adolescent idiopathic scoliosis is the most common type of idiopathic scoliosis and the most common type of scoliosis overall. Progressive curvature may be predicted by a combination of physiologic and skeletal maturity factors and curve magnitude. Small curves in more mature patients have a substantially lower risk of progression (about 2%) than larger curves in more immature patients, in whom the risk is much higher (risk may approach or exceed 70%).
Treatment recommendations for adolescent idiopathic scoliosis are driven almost totally by curve magnitude (the only caveat being that brace treatment is thought to be effective only in patients who are still growing). It is thus somewhat ironic to note that stated recommendations urge observation for curves less than 30°, bracing of curves that reach the 30-40° range, and consideration of surgery for curves that exceed 40°. This amounts to a 10° window between observation and major spinal surgery. It is even more ironic to note that 10° is a commonly discussed margin of error for measuring such scoliotic curves. Additional patient factors may also influence some orthopedic surgeons to brace patients with curves measuring less than 30° or in excess of 40°. For instance, a rapidly progressive curve in a 12-year-old child that suddenly goes from 16-26° may easily prompt bracing.
When it comes to surgical considerations, patients with adolescent idiopathic scoliosis may be functionally subdivided into those patients in whom significant anterior spinal growth is a concern and those in whom it is not. This amounts to a quantification of risk of development of the complication known as crankshaft phenomenon. This can have a major impact on the surgical treatment plan in that a child at significant risk for crankshaft phenomenon will require an anterior spinal fusion procedure.
Much effort has been devoted to predicting which patients may suffer from this continued anterior spinal growth that results in progressive angulation and rotation of the spine.. In fact, a hierarchy of risk can be constructed in which progressively more precise estimates can be made. In this hierarchy, the presence of a radiographic Risser sign and reaching menarche are somewhat predictive but less so than closure of the triradiate cartilage, and reaching one's peak height velocity is perhaps the most powerful predictor of being at rather low risk for the crankshaft phenomenon.
The anatomy relevant to idiopathic scoliosis is that of the thoracic and lumbar spine. Key points regarding developmental anatomy of the spine are outlined below. Scoliosis surgery is usually still performed via a posterior approach to the spine; thus, significant discussion of posterior anatomy is provided. A growing appreciation and need for anterior surgical procedures for scoliosis also demands additional discussion of retroperitoneal anatomy and intrathoracic anatomy, especially as it relates to video-assisted thoracoscopic surgery (VATS).
Significant growth, development, and differentiation occur as a single-celled zygote progresses to become an approximately 100 trillion–celled adult human. Identifiable spine development has begun by the third week of gestation. First, the neural tube forms. Later, paired somites appear (at 4.5 weeks' gestation) and spinal nerves are present by the sixth gestational week. A discernible cartilage model of the spine is present by the seventh week of gestation. The bone and cartilage of the spine are mesodermal derivatives, as are significant portions of the cardiovascular and urogenital systems. This explains the frequent coexistence of congenital spine anomalies with congenital cardiac and kidney defects. Thus, gestational weeks 3-7 are very important in the development of all of these major body systems.
Postnatal spinal growth also must be understood and appreciated. Alain Dimeglio has shown that the majority of spinal canal diameter (about 90%) has been achieved by age 5 years. By age 10 years, approximately 80% of sitting height has also been achieved. During adolescence, radiographic evidence of ossification of the growth cartilage of the vertebral bodies occurs. Prior to this, these completely cartilaginous growth plates remained nestled between their respective vertebral bodies and intervertebral disks.
The major superficial muscles of the back are not often directly visualized during posterior surgical approaches for scoliosis, but they must not be forgotten. These muscles include the trapezius, rhomboid major, rhomboid minor, and latissimus dorsi. Using an animal model, Kawaguchi et al showed that significant posterior muscle injury can be induced by the pressure exerted by surgical retractors. This certainly makes a case for intermittent removal and replacement of such retractors during the course of posterior spinal surgery.
The route for exposure of the posterior spinal elements passes through the cartilaginous apophyses of the spinous processes. These structures, often referred to as the cartilaginous caps, are systematically split in the midline to allow sequential subperiosteal dissection of the spinous processes, laminae, facet joints, and transverse processes. The laminae of the thoracic vertebrae spread out from the midline like wings and flow upwards (cranially) in the direction of the transverse processes. The facet joints of the thoracic spine are shingled in a coronal plane such that the inferior facet that contributes to each joint is located posteriorly and the superior facet is located anteriorly. The thickness of the interior and superior facets of the thoracic spine range from about 3-5 mm. The thoracic facet joints are located a mere 7-11 mm from the midline of the posterior spine.
Progressing from the thoracic to the lumbar spine, important differences are noted. The V-shaped laminae of the thoracic spine give way to the butterfly-shaped laminae of the lumbar spine. This orientation change is important for the surgeon to remember when exposing these bony elements. The facet joints of the thoracic spine, which are oriented in more of a coronal plane, transition into the more sagittally oriented facet joints of the lumbar spine. The transverse processes of the thoracic spine, which seem to flow directly up and away from the laminae, change significantly in the lumbar spine such that they are no longer in close proximity to the laminae and are located anterior and inferior to the lumbar facet joints.
The ribs are also obviously absent in the lumbar vertebrae. What some consider a rib remnant does persist and is referred to as a mamillary body or mamillary process. It is most pronounced near the thoracolumbar junction but may be identified on nearly all of the lumbar segments. In the sagittal plane, one must also appreciate that the normal gentle kyphosis of the thoracic spine reaches its apex at about the T7 through T9 region. Below this, a rather definite transition to lumbar lordosis occurs, with an apex around the L3 level. Thoracic kyphosis typically ranges from 20-40° (Cobb measurements usually taken from the top of T3 to the bottom of T12). Some authors have stated that up to 50° of thoracic kyphosis should be considered normal. Normal lumbar lordosis is considered by some to range from 35-55° (Cobb measurements usually taken from the top of L1 to the top of L5).
Anterior scoliosis surgery involves 3 main strategies, as follows:
Anterior lumbar or thoracolumbar surgery through a retroperitoneal approach that may or may not involve a diaphragmatic incision
Anterior thoracic surgery via traditional open thoracotomy
Anterior thoracic surgery via VATS
Various factors relative to skeletal maturity, curve location, and curve flexibility help determine which (if any) of these anterior surgeries may be appropriate.
The most common reason to use the retroperitoneal approach is for an instrumented anterior thoracolumbar spinal fusion. The most common curve pattern in that particular type of scoliosis is an apex left curve pattern, and as such, the patient is usually positioned lying on the right side. This position is advantageous in that it provides the best access to the scoliotic spine and it also places the thick-walled aorta closer to the surgical field (as opposed to the thin-walled inferior vena cava). After superficial muscle dissection, the surgeon approach proceeds through the bed of the rib that corresponds with the highest vertebrae in which instrumentation is planned. This is often either the ninth or tenth rib, with the rib itself being harvested for later use as a bone graft.
Careful dissection is then performed to mobilize the peritoneum (with its contents) in an anterior direction; it is peeled off of the undersurface of the diaphragm. Posterior division of the diaphragm (leaving about a 2-cm cuff for repair) helps to avoid damage to the phrenic nerve. Diaphragmatic division begins with splitting of the costal cartilage and proceeds in a posterior direction with intermittently placed tagging sutures to aid in closure.
The remainder of the retroperitoneal approach to the thoracolumbar spine requires careful superior retraction of the lung, anterior retraction of the peritoneum (with associated aorta and ureter), and posterior retraction of the iliopsoas musculature. Careful identification and division of the segmental vessels (overlying the vertebral bodies) is carried out with either electrocautery or ligatures. Small sympathetic nerve branches in this same area are sacrificed during this stage of the exposure. This results in at least a transient period in which the left foot (for a left-sided approach) will be both pinker and warmer than the contralateral foot. At times, this may result in nursing personnel notifying the surgeon that the contralateral foot is pale and cold, but in reality, the foot ipsilateral to the exposure has changed.
Open thoracotomy might be performed either for anterior thoracic spine release followed by posterior fusion or for anterior thoracic spine fusion with instrumentation. The most common curve pattern to address with this approach would be a right thoracic curve, and as such, the patient would be positioned with the right side upward.
A similar rib selection and resection technique may be used if desired. From the interior of the chest, the intercostalis musculature (located between each of the ribs) can be seen. Identification of the azygous vein (anteriorly oriented along the vertebral bodies) is necessary. Further medial (ie, central) and running parallel to the azygous vein is the thoracic duct. Several portions of the sympathetic chain may be sacrificed as the segmental vessels overlying the thoracic vertebral bodies are divided and mobilized anteriorly and posteriorly. Blood flow changes similar to those noted in the retroperitoneal approach may be noted in the right foot (for a right thoracotomy).
In addition to this, thoracic surgical dissection carries with it the possibility of sacrificing branches to the greater splanchnic nerve, which would theoretically decrease visceral referred pain that one might feel from an inflamed gallbladder or similar condition.
Thoracoscopic appreciation of the anatomy of the thoracic spine is becoming more common as endoscopic anterior release and fusion is rapidly moving from being considered an innovation to standard practice. Just as arthroscopic knee surgeons enjoyed an expansion in visualized anatomy compared to that visible with knee arthrotomies, the endoscopic spine surgeon benefits from much greater intrathoracic latitude. Most VATS also involve the right thoracic cavity, and this discussion focusses on that particular side.
Proper rib counting and visualization of the superior intercostal vein (formed by the confluence of the second, third, and fourth intercostal veins) as it empties into the azygous vein are necessary steps to orient the surgeon. Beyond this, one also notes the mounds and valleys of the thoracic spine, with the mounds being the disks and the valleys being the vertebral bodies with the segmental vessels that overly them.
The same anatomy outlined in the thoracotomy discussion still clearly applies, but further endoscopic fine points are needed. Specifically, the thoracic spine may be considered to be composed of 3 separate fields with important anatomic nuances. The upper field may be considered to be T2-T5, the middle field may be considered to be T6-T9, and the lower field may be considered to be T10-L1. The upper field is dominated by the superior intercostal vein, and it is characterized by the fact that the rib heads tend to completely span their respective disk spaces and articulate with 2 vertebral bodies. This results in a rib such as the third rib coming directly into the region of the T2-T3 disk space such that it will articulate with both the T2 and T3 vertebral bodies. In the middle field, the rib head once again comes directly in toward the disk space, but now, it rather firmly attaches itself only to the disk space proper.
In the lower field, the rib head articulates directly with its corresponding vertebral body. Thus, in the lower field, the 11th rib is traced to its corresponding vertebral body and then moves directly cephalad to reach the T10-11 disk or directly caudad to reach the T11-12 disk. Once the vertebral bodies have been exposed in a skeletally immature patient, the growth cartilage of the vertebral endplate can be visualized. It has an odd tendency to appear green in color (a quirk of endoscopic optics) and is colloquially referred to as a Wolf line in honor or Randall K. Wolf.
Few, if any, absolute contraindications exist regarding scoliosis care, just as few, if any, absolute indications for intervention exist. Accepted contraindications for bracing include skeletal maturity and excessive curve magnitude. Thoracic lordosis and certain curve patterns such as double thoracic curves also have been offered as at least relative contraindications to bracing.
The main contraindication to posterior scoliosis surgery would be medical instability and inability to survive surgery. Anterior scoliosis surgery would also be contraindicated in these patients, as well as in those with a precarious pulmonary status.