In a prospective trial we performed MRI of the spine and hind brain in 31 patients with scoliosis of onset between the ages of four and 12 years.

In eight patients (26%) there was a significant neuroanatomical abnormality; there were six cases of Chiari-1 malformation associated with a syrinx, one isolated Chiari-1 malformation and one astrocytoma of the cervical spine. Four of these patients had left-sided curves.

There were no clinical features which could reliably identify those patients with abnormalities on MRI. In particular, the unilateral absence of abdominal reflexes was found to be non-specific (1 of 8 of patients with neuroanatomical abnormalities (12.5%) v 2 of 23 with normal scans (8.7%)).

In view of the established risks of surgical correction of scoliosis in the presence of undecompressed syringomyelia and the possible improvement that may follow decompression of the foramen magnum, we feel that MRI of all patients with scoliosis of juvenile onset should be obligatory.

There is a high incidence of spinal deformity in children with the Prader-Willi syndrome. We have encountered major complications following spinal surgery in this condition. We report our experience and conclude that spinal surgery is a formidable undertaking and the risks should be appreciated by the surgeon and the parents.

A survey was conducted to document the results of bracing and spinal fusion for scoliosis associated with osteogenesis imperfecta. Observations were made of 121 patients who underwent treatment by bracing or spinal fusion and who had been treated by 51 orthopaedic surgeons in 14 countries. The average curve before bracing measured 43 degrees. The braces were ineffective in stopping progression even in small curves. We were unable to determine whether braces slowed the rate of progression of curvature. The average age at fusion was 15 years 7 months, the average curve before operation measured 74 degrees, and the average correction was 36 per cent. The high incidence of complications was related to the size of the curve before spinal fusion, the use of Harrington instrumentation, and the presence of associated kyphosis. In the absence of pseudarthrosis or kyphosis, late bending of the fused spine did not seem to occur.

A survey has been undertaken of the various complications of halo-pelvic distraction in 118 patients with scoliosis prior to spinal fusion. In the first sixty-two patients the standard solid distraction rods were employed. The neurological complications included ten cases of cranial nerve lesions and two cases of paraplegia, one of them permanent. Springs were then incorporated in the distraction rods so as to allow direct readings ofthe distraction forces, and a total force of 18 kilograms was not exceeded in the last fifty-six patients. No further serious neurological complications occurred, but the amount of correction achieved in the adolescent and juvenile idiopathic types of scoliosis was reduced.

1. The production of scoliosis in young animals by resection of the posterior ends of the ribs is described and the etiological mechanisms discussed. It is suggested that retardation of posterior rib growth, removal of mechanical support from one side of the spine, and disturbance of proprioceptive impulses are the factors which initiate the deformity.

2. Some or all of these mechanisms may contribute to the production of certain human curves, for instance impaired rib growth and support in post-poliomyelitic deformities, proprioceptive and reflex disturbances in syringomyelia.

3. Therapeutically resection of the heads and necks of the ribs on the concave side of thoracic idiopathic curves is followed by improvement in some cases. Exactly how much improvement, in what proportion of curves, and for how long it will be maintained cannot be defined at present, but therapeutically worthwhile effects have been obtained, especially in children under five years old; even if this improvement is followed by later progression, several years of freedom from bracing may have been achieved, and the operation has not in any way interfered with subsequent correction and posterior fusion if this has seemed necessary. It is thought that this operation may have a small but useful role in the early management of idiopathic scoliosis, especially in a young child who is not responding well to bracing.

1. One hundred babies under the age of one year with untreated structural idiopathic scoliosis have been studied and the outcome assessed.

2. Ninety-two recovered spontaneously. Five developed progressive curves of bad prognosis and three developed secondary structural (double primary) scoliosis.

3. It is suggested that intrauterine moulding may cause the deformity.

1. By unilateral resection of the posterior ends of the sixth to eleventh ribs including the costal parts of both costo-vertebral joints, progressive scoliosis can regularly be provoked in young rabbits. Rotation of the vertebrae is prominent in the experimental deformity.

2. Although severe progressive scoliosis can be provoked by a surgical procedure we do not yet know the deforming forces which are released by the operation, but the way lies open for accurate studies on these factors.

3. It seems possible that studies on experimental progressive scoliosis may provide us with new methods to counteract or cure scoliosis in children. The goal is a means to reverse the deforming forces during growth so that the child's spine is straight when growth ceases.

1. Posterior fusion of the spine in scoliosis cannot be relied upon to maintain correction of the curve or to prevent progression of a vicious resistant curve. It can, however, hold to some extent the correction of a mobile curve and the compensation of a fixed curve.

2. Despite generally poor results as assessed radiographically, the clinical improvement is often gratifying. Most patients claim to be greatly improved: the spine feels stronger, there is less fatigue, and balance is better controlled. Moreover, visible deformity may be improved markedly even though the anatomical correction as observed radiographically is slight (Figs. l0 and 11).

3. It is believed that the true cause of relapse is that the bone formed from sliver grafts remains immature for a long time. Even when incorporated with the immature bone of the child's spine or the mature bone of the adult spine, it remains soft and resilient. When subjected to the stresses and strains of weight bearing and gravity, and then to the unnatural forces which initiated or perpetuated the scoliosis, this immature bone undergoes remodelling to Wolff's Law—like the neck of the femur after slipping of the upper femoral epiphysis. The forces that alter the grafted bone are not only lateral forces but also—perhaps more important—rotational forces. There seems to be a definite link between the degree of rotation and the amount of relapse, correction being maintained best when rotation is least.

1. The radiographic appearance of normal thoracic and lumbar vertebrae at 15-degree intervals of rotation is described. Each image can be identified by its characteristic features.

2. The appearance on antero-posterior radiographs of apical vertebrae in scoliosis closely resembles the normal at each phase of rotation, on the basis of which an image-matching method is proposed for estimating rotation in scoliosis.

3. The method gives only approximate values of rotation but has the advantage of being able to monitor rotation through 90 degrees.

It is suggested that the operation of partial costectomy is so beneficial psychologically to some young scoliotic patients that it is worth the very small physiological cost demonstrated here in patients who found their "hump" sufficiently embarrassing to curtail their normal social life.

1. Resolving infantile scoliosis is transient and unimportant; progressive infantile idiopathic scoliosis can be catastrophic.

2. To be able to differentiate the two at an early stage is a considerable advance. This is important for many reasons, but particularly for parents who are anxious for the future of an infant with a small curve which looks so innocent but which can be so malignant.

3. With the new observations reported by Mehta on the difference of the angles between the apical vertebra and its two ribs, and on the radiological relationship of these rib heads to the vertebral body, the prognosis is now almost wholly reliable.

4. Our former clinical impression that all cases with compensatory curves are progressive has now been verified.

5. At last an early distinction between progressive and resolving scoliosis can be made with confidence.

1. Ten children with scoliosis and cerebral palsy of various types have been reviewed. All underwent operation for correction and stabilisation of the spinal curve, and spinal fusion.

2. Three of the ten patients required supplemental surgery in the form of regrafting, with or without reinsertion of Harrington rods. All have shown considerable correction of the curve, and in all cases the fusion appears to be consolidated. Operation has given these children stable spines which are compensated. Their ability to sit, and in some cases to stand, has improved.

3. In many such cases of scoliosis complicating cerebral palsy Harrington instrumentation and spinal fusion is the only feasible effective form of treatment.

Severe kypho-scoliosis, lateral curvature and lordo-scoliosis are ultimately caused by disturbance of vertebral growth. The results of treatment by destroying the growth potential opposite the area of growth inhibition have been encouraging. When the operation has been adequate further deterioration has been prevented; in younger children there has been improvement with further growth. It is important that the growth arrest should be at the right site and that it should be sufficiently extensive. Accurate pre-operative diagnosis of the type and extent of the curve is important.

1. The belief that the cessation of spinal growth and curve progression coincides with the completion of growth in the iliac apophyses has been confirmed in a review of material from 224 cases. This applies also to paralytic curves.

2. In a high number of cases this ossification centre showed an asymmetrical development on the two sides of the pelvis. The appearance of a separate posterior centre of ossification is also common, and probably represents an advanced stage in the growth of the iliac apophysis.

3. Menarche and the growth of the apophyses of the vertebral bodies almost always occurred in advance of the iliac apophyses. They should be regarded as early signs of maturation, not reliable in the prognosis of curve progression.

4. The growth of the iliac apophysis appeared to be unaffected by poliomyelitis.

We reviewed retrospectively the role of monitoring of somatosensory spinal evoked potentials (SSEP) in 99 patients with neuromuscular scoliosis who had had operative correction with Luque-Galveston rods and sublaminar wiring.

Our findings showed that SSEP monitoring was useful and that a 50% decrease in the amplitude of the trace optimised both sensitivity and specificity. The detection of true-positive results was higher than in cases of idiopathic scoliosis, but the method was less sensitive and specific and there were more false-negative results. In contrast with the findings in idiopathic scoliosis, recovery of the trace was associated with a 50% to 60% risk of neurological impairment.

Only one permanent injury occurred during the use of this technique, and any temporary impairment resolved within two months.

We reviewed 47 patients with neurofibromatosis and dystrophic spinal deformities; 32 of these patients had been untreated for an average of 3.6 years and in them the natural history was studied. The commonest pattern of deformity at the time of presentation was a short angular thoracic scoliosis, but with progression the angle of kyphosis also increased. Deterioration during childhood was usual but its rate was variable. Severe dystrophic changes in the apical vertebrae and in particular anterior scalloping have a poor prognosis for deterioration. The dystrophic spinal deformity of neurofibromatosis requires early surgical stabilisation which should be by combined anterior and posterior fusion if there is an abnormal angle of kyphosis or severely dystrophic apical vertebrae. Some carefully selected patients can be treated by posterior fusion and instrumentation alone.