Infantile developmental thoracolumbar kyphosis with segmental subluxation of the spine.

We report five children who presented at the mean age of 1.5 years (1.1 to 1.9) with a progressive thoracolumbar kyphosis associated with segmental instability and subluxation of the spine at the level above an anteriorly-wedged hypoplastic vertebra at L1 or L2. The spinal deformity appeared to be developmental and not congenital in origin. The anterior wedging of the vertebra may have been secondary to localised segmental instability and subsequent kyphotic deformity. We suggest the term 'infantile developmental thoracolumbar kyphosis with segmental subluxation of the spine' to differentiate this type of deformity from congenital displacement of the spine in which the congenital vertebral anomaly does not resolve. Infantile developmental kyphosis with segmental subluxation of the spine, if progressive, may carry the risk of neurological compromise. In all of our patients the kyphotic deformity progressed over a period of three months and all were treated by localised posterior spinal fusion. At a mean follow-up of 6.6 years (5.0 to 9.0), gradual correction of the kyphosis was seen on serial radiographs as well as reconstitution of the hypoplastic wedged vertebra to normality. Exploration of the arthrodesis was necessary at nine months in one patient who developed a pseudarthrosis.

Segmental vessel ligation in patients undergoing surgery for anterior spinal deformity.

Segmental vessel ligation during anterior spinal surgery has been associated with paraplegia. However, the incidence and risk factors for this devastating complication are debated. We reviewed 346 consecutive paediatric and adolescent patients ranging in age from three to 18 years who underwent surgery for anterior spinal deformity through a thoracic or thoracoabdominal approach, during which 2651 segmental vessels were ligated. There were 173 patients with idiopathic scoliosis, 80 with congenital scoliosis or kyphosis, 43 with neuromuscular and 31 with syndromic scoliosis, 12 with a scoliosis associated with intraspinal abnormalities, and seven with a kyphosis. There was only one neurological complication, which occurred in a patient with a 127 degrees congenital thoracic scoliosis due to a unilateral unsegmented bar with contralateral hemivertebrae at the same level associated with a thoracic diastematomyelia and tethered cord. This patient was operated upon early in the series, when intra-operative spinal cord monitoring was not available. Intra-operative spinal cord monitoring with the use of somatosensory evoked potentials alone or with motor evoked potentials was performed in 331 patients. This showed no evidence of signal change after ligation of the segmental vessels. In our experience, unilateral segmental vessel ligation carries no risk of neurological damage to the spinal cord unless performed in patients with complex congenital spinal deformities occurring primarily in the thoracic spine and associated with intraspinal anomalies at the same level, where the vascular supply to the cord may be abnormal.

James IV Lecture: congenital deformities of the spine.

Congenital anomalies of the vertebrae producing a scoliosis, kyphoscoliosis or kyphosis are potentially serious conditions, which can, on occasion, result in an extremely severe rigid spinal deformity with possible spinal cord compression. The key to successful management depends on: (1) Early diagnosis while the curve is still small. (2) Anticipation of the likely prognosis based on the type and site of the vertebral anomaly, the degree of growth imbalance it produces and the amount of spinal growth remaining. (3) Preventing progression of the deformity and this may necessitate surgical treatment in the first few years of life. It is much better to carry out a relatively simple operation to balance the growth of the spine at an early stage than to wait and perform potentially hazardous anterior and posterior spinal surgery as a salvage procedure at a later stage.

The surgical management of congenital kyphosis and kyphoscoliosis.

STUDY DESIGN: A retrospective study of surgery for congenital kyphosis and kyphoscoliosis. OBJECTIVE: To assess the effectiveness of different types of spine surgery in the management of congenital kyphosis and kyphoscoliosis. SUMMARY OF BACKGROUND DATA: Congenital kyphosis and kyphoscoliosis are much less common than congenital scoliosis but potentially more serious, because these curves can progress rapidly and Type I deformities can lead to spinal cord compression and paraplegia. No one operative procedure can be applied to all types and sizes of deformity. The method of surgical treatment depends on the age of the patient, the type and size of the deformity, and the presence or absence of spinal cord compression causing a neurologic deficit. METHODS: Sixty-five patients with a congenital kyphosis (n = 14) or kyphoscoliosis (n = 51) were treated by five different methods of spine arthrodesis: prophylactic posterior arthrodesis before age of 5 years (n = 11), posterior arthrodesis after age 5 years without instrumentation (n = 26) and with instrumentation (n = 12), combined anterior and posterior arthrodesis without instrumentation (n = 7) and with instrumentation (n = 9). Six patients had preoperative lower limb spastic paraparesis caused by spinal cord compression. The mean age at surgery was 9 years 6 months (range, 11 months to 25 years), and all 65 patients were observed for a minimum of 2 years (mean 6 years 6 months, range 2 to 18 years). Fifty-seven patients reached skeletal maturity. RESULTS: A posterior arthrodesis performed before the age of 5 years resulted in a gradual reduction of the kyphosis by a mean 15 degrees in 9 of the 11 patients, followed up for a mean of 11 years, whose initial kyphosis was less than 55 degrees. Patients treated after the age of 5 years by a posterior arthrodesis followed by cast application had poor correction and a high incidence of pseudarthrosis. This was not significantly improved by the addition of posterior instrumentation. For curves greater than 60 degrees, the most successful results were achieved by an anterior spinal release and arthrodesis with strut graft correction followed by posterior arthrodesis with instrumentation (if possible). CONCLUSION: All patients with a Type I or Type III congenital kyphosis or kyphoscoliosis should be treated by a posterior arthrodesis before the age of 5 years and before the kyphosis exceeds 50 degrees. A kyphosis that does not reduce to less than 50 degrees as measured on the lateral spine radiograph made with the patient supine requires an anterior release and arthrodesis with strut grafting followed by posterior arthrodesis with instrumentation (if possible).

Natural history of congenital kyphosis and kyphoscoliosis. A study of one hundred and twelve patients.

BACKGROUND: Congenital kyphosis and kyphoscoliosis are much less common than congenital scoliosis. However, they are potentially more serious because compression of the spinal cord and paraplegia sometimes develop. The goals of the present study were to document the natural history of congenital kyphosis and kyphoscoliosis and to determine the stage at which the natural progression should be interrupted by treatment. METHODS: We reviewed the medical records and radiographs of the spine of 112 consecutive patients. Sixty-eight patients had a type-I kyphosis due to an anterior failure of vertebral-body formation, twenty-four had a type-II kyphosis due to an anterior failure of vertebral-body segmentation, and twelve had a type-III kyphosis due to a combination of anomalies; the deformities of the remaining eight patients could not be classified. Eighty-five skeletally immature, untreated patients were first evaluated at a mean age of six years and nine months (range, two months to sixteen years and three months), and twenty-seven patients were skeletally mature at the time of the first visit. Sixty-three of the eighty-five skeletally immature patients were observed without any treatment for a mean period of six years and six months (range, one to sixteen years) before skeletal maturity, and the remaining twenty-two patients had a posterior arthrodesis of the spine soon after the initial visit. At skeletal maturity, forty-one patients had not been treated and sixty-eight had had an arthrodesis of the spine. The remaining three patients had not yet reached skeletal maturity at the time of the most recent follow-up. RESULTS: The apex of the kyphosis was seen at all levels but was most frequent between the tenth thoracic and the first lumbar level (seventy-four patients; 66 percent). There was no relationship between the severity of the kyphosis and its location in the spine. Progression of the curve was most rapid during the adolescent growth spurt and stopped only at skeletal maturity. Progression was most rapid and the magnitude of the curve was the greatest in type-III kyphosis (twelve patients) followed by type-I kyphosis due to a posterolateral quadrant vertebra (thirty-nine patients), a posterior hemivertebra (eight patients), a butterfly vertebra (fifteen patients), and a wedged vertebra (six patients). A kyphosis due to two adjacent type-I vertebral anomalies progressed more rapidly and produced a more severe deformity than did a similar single anomaly. The prognosis for type-II kyphosis was variable and was much more severe when an anterolateral unsegmented bar had produced a kyphoscoliosis (nine patients) than it was when a midline anterior bar had produced a pure kyphosis (fifteen patients), which usually progressed slowly. Spontaneous neurological deterioration due to compression of the spinal cord occurred in ten patients (seven of whom had a type-I kyphosis and three of whom had an unclassifiable anomaly) at a mean age of thirteen years and eight months, and one other patient (with an unclassifiable anomaly) had spastic paraparesis at the age of twenty-eight years. CONCLUSIONS: Congenital kyphosis and kyphoscoliosis are uncommon deformities with the potential to progress rapidly, resulting in severe deformity and possible neurological deficits. A thorough knowledge of the natural history is essential in the planning of appropriate and timely treatment to prevent progression of the deformity and neurological complications.

Congenital scoliosis caused by a unilateral failure of vertebral segmentation with contralateral hemivertebrae.

STUDY DESIGN: The medical records and serial spine radiographs of 59 consecutive patients with congenital scoliosis caused by unilateral unsegmented bar with contralateral hemivertebrae were reviewed. OBJECTIVES: To study the presentation, natural history, and treatment of these patients. SUMMARY AND BACKGROUND DATA: This is the least common type of congenital scoliosis. METHODS: The mean age at diagnosis was 4 years 1 month. Forty-three patients were observed without treatment for a mean of 6 years and 1 month. Prophylactic arthrodesis was performed in 10 patients before they were 5 years old. Thirty-five patients had a corrective procedure and arthrodesis after they were 5 years old. RESULTS: Thoracolumbar curves had the worst prognosis. Without management all but two exceeded 50 degrees when the patients were 2 years old. All untreated curves exceeded 88 degrees. Midthoracic curves had only a slightly less severe prognosis, and all but one exceeded 40 degrees by the time the patient was 2 years old. All untreated curves exceeded 70 degrees. In eight of the 14 patients whose congenital curves had their apexes at T5, T6, or T7, a long secondary structural curve developed on the opposite side in the thoracolumbar region, and this contributed significantly to the overall deformity. Occult intraspinal anomalies were present in 24 patients (41%). Surgical treatment after the patient was 5 years old was not successful in producing significant correction of these severe rigid deformities. CONCLUSION: These patients have the most rapidly progressive and severely deforming of all types of congenital scoliosis. All midthoracic, thoracolumbar, and lumbar curves require immediate prophylactic surgical treatment by anterior and posterior arthrodesis--preferably in the first year of life.

Osteotomy of the cervical spine in ankylosing spondylitis.

Fifteen patients with ankylosing spondylitis who had developed a severe flexion deformity of the cervical spine which restricted their field of vision to their feet, were treated by an extension osteotomy at the C7/T1 level. The operation was performed under general anaesthesia with the patient in the prone position and wearing a halo-jacket. Three had internal fixation using a Luque rectangle and wiring. Their mean age was 48 years. Before operation the mean cervical kyphosis was 23 degrees; this was corrected to a mean of 31 degrees of lordosis, a mean correction of 54 degrees. All the patients were able to see straight ahead. One patient with normal neurology soon after operation became quadriparetic after one week; two others had unilateral palsy of the C8 root, which improved. There was subluxation at the site of osteotomy in four patients, and two of them developed a pseudarthrosis which required an anterior fusion.

Juvenile idiopathic scoliosis. Curve patterns and prognosis in one hundred and nine patients.

We reviewed the medical records and radiographs of 109 consecutive patients who had juvenile idiopathic scoliosis. The sixty-seven girls and forty-two boys were a mean of six years and ten months old (range, three years and four months to nine years and eleven months old) when the curve was recognized. One hundred and four patients had a progressive curve: twenty-eight had a single mid-thoracic curve with the apex usually at the eighth thoracic vertebra (Group 1A), twenty-nine had a major mid-thoracic curve with the apex usually at the eighth thoracic vertebra and a secondary minor lumbar curve (Group 1B), twenty-seven had a single thoracic curve with the apex usually at the ninth or tenth thoracic level (Group 2), eight had a single thoracolumbar curve with the apex at the twelfth thoracic level (Group 3), and twelve had a major lumbar curve with the apex at the second or third lumbar level and a secondary minor thoracic curve (Group 4). Five patients (5 per cent) had a resolving curve. Eighty-nine of the patients who had a progressive curve were followed to skeletal maturity. Eighty-eight patients were managed with a brace. The curve progressed at a rate of 1 to 3 degrees per year before the age of ten years and 4.5 to 11 degrees per year after the age of ten years. In sixty-seven of the eighty-four patients in Groups 1 and 2, a spinal arthrodesis was performed before the age of fifteen years (mean age, eleven years and ten months; range, nine years and three months to fourteen years and eight months), at which time the mean curve was 47 degrees (range, 24 to 90 degrees). Eight patients were not seen by us until they were fifteen years old or more, at which time the thoracic curve was 74 to 120 degrees; a spinal arthrodesis was done in seven. The curves in Groups 3 and 4 had a more benign prognosis, and only three patients in these two groups had an arthrodesis. The pattern of the final curve was not always apparent at an early stage, and there was extension of the primary curve or development of secondary structural curves with progression. The chief prognostic feature at an early stage was the level of the most rotated vertebra at the apex of the primary curve, and the final pattern of deformity was defined by the level of the caudad neutral vertebra in the primary thoracic curve.

Spinal deformity in Ehlers-Danlos syndrome. Five patients treated by spinal fusion.

Five patients with classical Ehlers-Danlos syndrome developed severe spinal deformities. Two were shown to have type-VI collagen abnormalities. Three had a double structural scoliosis of the thoracic and lumbar regions, one had a single thoracic scoliosis and one had a thoracic kyphosis. The curves first developed before the age of four years, and were not controlled by bracing. Major corrective surgery with posterior fusion was performed at a mean age of 11 years 8 months. Excessive blood loss could be controlled and although wound haematoma and dehiscence were common, they did not provide major problems. The spinal fusions healed satisfactorily.

Fibrocartilaginous mesenchymoma of the fifth lumbar vertebra treated by vertebrectomy.

STUDY DESIGN: This is the first report of a fibrocartilaginous mesenchymoma in the spine. SUMMARY OF BACKGROUND DATA: This is a rare bone tumor composed of islands of hyaline cartilage in a collagen-producing spindle cell stroma. Seven cases of fibrocartilaginous mesenchymoma have been reported previously. Of these, four occurred in the long bones. METHODS: The tumor is hypercellular with mild nuclear hyperchromasia. Few mitotic figures are present. However, it is highly infiltrative, and in the present patient, it completely encircled the spinal cord. Vertebrectomy was required to ensure tumor eradication. RESULTS: Five years after tumor resection, femoral head allograft replacement of the vertebral body, and posterior spinal stabilization, there was no evidence of tumor recurrence.

The effect of Luque-rod instrumentation on the sagittal contour of the lumbosacral spine in adolescent idiopathic scoliosis and the preservation of a physiologic lumbar lordosis.

The changes in the sagittal alignment of the lumbar spine were investigated in 28 patients with adolescent idiopathic scoliosis undergoing long posterior spinal fusion to L4 or L5 with contoured Luque rods and segmental sublaminar wiring. The lumbar lordosis over the instrumented levels was preserved, and there was no compensatory hyperlordosis of vertebral segments distal to the fusion. In situations where long posterior spinal fusions are indicated, instrumentation with contoured Luque rods and segmental sublaminar wiring can preserve the normal sagittal alignment of the lumbosacral spine.

Luque rod instrumentation in the treatment of adolescent idiopathic scoliosis. A comparative study with Harrington instrumentation.

Adolescent idiopathic scoliosis in 152 patients was treated by Luque L-rod instrumentation and early mobilisation without external support. This series was compared with a matched group of 156 patients treated by Harrington instrumentation and immobilised in an underarm jacket for nine months. All the operations in both groups were performed by one surgeon and the patients were followed prospectively for more than two years. Correction of the scoliosis in the frontal plane was similar in both groups. However, the normal sagittal contour was better maintained with Luque rods, especially in the thoracolumbar and lumbar regions, and provided less loss of correction than with Harrington rods. Neither method significantly derotated the scoliosis. All the patients with Luque instrumentation developed a solid fusion despite breakage of the sublaminar wires at one or two levels in 4.9%. There were no major neurological complications with either type of instrumentation.

The effect of Luque segmental sublaminar instrumentation on the rib hump in idiopathic scoliosis.

The change in back shape after Luque segmental sublaminar instrumentation was assessed in the frontal, sagittal, and transverse planes in 61 patients with adolescent idiopathic scoliosis using the Integrated Shape Investigation System (ISIS) and standard radiographic techniques. Luque instrumentation was found to be an effective method of correcting thoracic and thoracolumbar curves in the frontal plane with a 59% and 63% respective reduction in the size of the preoperative Cobb angle. Despite the frontal plane correction, however, the ISIS scan showed that of the 40 single thoracic curves, the rib hump was reduced in only 6 patients, was unchanged in 27 patients, and was worsened slightly in 7 patients. By contrast, thoracolumbar and lumbar curves were corrected in all three planes with a significant cosmetic improvement.

Rates of muscle protein synthesis in paraspinal muscles: lateral disparity in children with idiopathic scoliosis.

1. The rate of paraspinal (multifidus) muscle protein synthesis was measured bilaterally at the top, apex and bottom of the thoracic curve in nine children with an idiopathic scoliosis, using the stable-isotope-labelled amino acid L-[1-13C]leucine. 2. No significant difference was observed in rates of muscle protein synthesis between the two sides of the spine, at the levels of the first vertebrae in neutral alignment at the top and bottom of the curve. However, in every patient, at the apex of the spinal curve, synthesis was higher on the convexity than on the concavity (0.077 +/- 0.04 %/h convex, 0.052 +/- 0.02 %/h concave, mean +/- SD, P less than 0.01). 3. Muscle RNA activity (microgram of protein synthesized h-1 microgram-1 of RNA) was lower at the curve apices on the concave than the convex side (0.019 +/- 0.09 microgram h-1 microgram-1 convex apex, 0.016 +/- 0.06 microgram h-1 microgram-1 concave apex, P less than 0.05). Activities were similar on the two sides at the top and bottom of the curve. 4. Differences in muscle histology between the two sides were also observed only at the apex, with a lower type I fibre diameter (50.9 +/- 8.5 micron convex, 38.3 +/- 2.4 microns concave, P less than 0.05) and a lesser proportion of type I fibres (63 +/- 12% convex, 49 +/- 9% concave, P less than 0.05) on the concavity. 5. The results are consistent with effects on muscle protein turnover secondary to an increased muscle contractile activity on the curve convexity and functional immobilization of the muscle on the curve concavity.

The long-term results of kyphectomy and spinal stabilization in children with myelomeningocele.

Ten myelomeningocele patients with a severe lumbar kyphosis were treated by resection of their kyphus, internal fixation, and spinal fusion. A mean kyphosis of 131 degrees was reduced to 44 degrees following the surgery. This was a very major procedure, associated with many complications. One patient died during the surgery and the remaining nine patients were followed for a mean of 7 years 4 months to skeletal maturity. The most successful methods of internal fixation were either by two Harrington distraction rods combined with compression across the osteotomy site (Group 3) or by a posteriorly applied AO plate (Group 2). A long posterior fusion extending from the mid-thoracic region to the sacrum was necessary to provide long-term stability and prevent the development of a thoracic lordosis. At skeletal maturity, all seven patients in Groups 2 and 3 had a flat back without pressure sores and all were able to sit upright without using their arms for support.

Anterior and posterior instrumentation and fusion of thoracolumbar scoliosis due to myelomeningocele.

Twenty-three patients with severe paralytic thoracolumbar scoliosis due to a myelomeningocele were treated by a two-stage procedure. Before operation the mean scoliosis was 98 degrees: after the first-stage procedure, an anterior spinal fusion and correction with Dwyer instrumentation, this was reduced to a mean of 45 degrees. Approximately two weeks later a posterior spinal fusion with Harrington instrumentation was performed, further reducing the scoliosis to a mean of 29 degrees. The pelvic obliquity also was reduced from a mean of 32 degrees to 6 degrees. Although such management carries risks (one patient died of cardiorespiratory failure after the first stage and one patient was made worse), 21 of the 23 patients had improved posture and function.

Hemivertebra as a cause of scoliosis. A study of 104 patients.

We studied 104 patients with a total of 154 hemivertebrae which had produced scoliotic curves. Of the hemivertebrae 65% were of a fully segmented (non-incarcerated) type, 22% were semi-segmented and 12% were incarcerated. We found that the degree of scoliosis produced depended on four factors: first, the type of the hemivertebra; secondly, its site; thirdly, the number of hemivertebrae and their relationship to each other; and finally, the age of the patient. Semi-segmented and incarcerated hemivertebrae usually do not require treatment. Fully segmented non-incarcerated hemivertebrae may require prophylactic treatment to prevent significant deformity.

The lumbar theco-peritoneal shunt syndrome and its surgical management.

Seven patients treated in infancy by a lumbar theco-peritoneal shunt for idiopathic communicating hydrocephalus presented later in childhood after developing a characteristic orthopaedic syndrome. This included a severe, rigid and progressive lumbar hyperlordosis, severe bilateral restriction of straight leg raising and abnormalities of stance and gait. Four of the patients, who had severe hyperlordotic curves of over 90 degrees, required operations to correct their extreme deformity. The recommended method of correction is a three-stage procedure: first, anterior wedge resection osteotomies at several levels in the lumbar spine, then a period of "90-90" femoral traction, and finally a posterior fusion and stabilisation using Harrington instrumentation. The results were good, with few complications.