We report our experience with carbon-fibre reinforced plastic (CFRP) plates in the management of 19 problem fractures complicated by either infection, nonunion, comminution or contamination. The combination offers secure fixation without inhibition of callus formation.

We describe the results of a policy of highly selective splintage for CDH, using knee plasters. No child suffered because splintage was withheld. In those who were treated the results were satisfactory and the proportion who required a subsequent operation was extremely low. Avascular necrosis was not a significant problem. The method, although a little more time consuming, appears to offer significant advantages over current alternatives.

A 15-year-old girl presented with a very large desmoid tumour in her buttock; it extended into the pelvis and thigh and would have required hindquarter amputation for its removal. This was not performed and the tumour underwent spontaneous regression. Fourteen years later the patient is alive and well. The suggestion is made that in some cases a more expectant approach to treatment might be justified for what is essentially a non-malignant condition.

We have studied the natural history of spontaneous dislocation of the hip in cerebral palsy, with particular reference to the pattern of neurological involvement. In patients with bilateral hemiplegia and severe involvement of the upper limbs the incidence of dislocation was very high (59%), while in those with diplegia and little involvement of the upper limbs, only 6.5% were affected. There was no evidence of dysplasia or instability of the hip in any of the patients with unilateral hemiplegia. A strong correlation was found between the stability of the hip and the patients' ability to walk. These findings have a bearing on clinical surveillance and also on the indications for prophylactic surgery.

We have studied the use of filamentous polyglycolic acid (Dexon) for the induction of neotendon in the calcaneal tendon of sheep. Uniformly good results were obtained, with the formation of a thick neotendon. However, in a control group the power of spontaneous regeneration of the tendon was studied; it was found that, provided overlengthening of the gap was prevented, an equally good tendon resulted. It is concluded that this particular model is not an appropriate one for testing neotendon induction, despite its use for this purpose in the past. The favourable results of using filamentous polyglycolic acid as a tendon replacement suggest that it should be further investigated (in a more suitable model) since it may well have useful clinical applications.

There are differences of opinion about the pathogenesis of Perthes' disease. All are agreed that it is due to ischaemia, but the cause of this and the size and number of infarctions are in dispute. Through the generosity of the contributors six whole femoral heads and core biopsies of five other cases have been studied radiographically and histologically. The findings ranged from an ischaemic arrest of ossification in the capital articular cartilage without infarction to multiple complete infarctions of the epiphysial bone. The ensuing reparative process contributes to the pathology, which is of a range to warrant grading or grouping.

The role of flexible carbon-fibre implants as substitutes for injured tendons and ligaments was investigated. These implants were simple to perform and were well tolerated by the patient. Repairs using carbon-fibres in 60 patients were successful, particularly in the almost insoluble problem of posterior cruciate laxity. The results in this report show that carbon-fibre implants have few disadvantages and have a future use in reconstructive procedures.

Allografts of immature joint cartilage from the knees of lambs were transferred heterotopically into an intramuscular site in animals which had been presensitised by two sets of skin grafts from the same donors. All of these grafts were found to be largely destroyed by the immune response as early as four weeks after transfer. Similar grafts transferred orthotopically into the knees of the recipients, on the other hand, were found to be thriving even after twelve weeks and evoked a minimal response. Heterotopic autografts also provoked a mild though non-specific inflammatory reaction which the orthotopic grafts did not. It is concluded that cartilage matrix is capable of protecting grafts to a remarkable degree even from a severe immunological assault but only when the nutrition is adequate. It is suggested that the conflicting results of similar previous experiments may be explained by variations in the nutritional state of the graft which may be affected by the technique of transplantation used.

The results of a long-term review of 102 hips in eighty-seven patients with Perthes' disease are described, the mean follow-up interval being seventeen years. All had been treated by an extremely rigorous conservative regime in which the patients were kept in hospital for an average period of twenty-six months, during which time they were confined to bed with the legs in wide abduction, first in traction and later in "broomstick" plasters to ensure "containment" of the femoral head. The patients were assessed by the joint clincial and radiological method described by Ratliff (1956). The results were very satisfactory, with only 2 per cent poor results and 10 per cent fair. The remaining 88 per cent were good. The radiological results at the end of treatment have also been compared with control series described by Catterall (1972) and with the osteotomy series of Lloyd-Roberts, Catterall and Salamon (1976). From this it appears that the described regime offers no benefit compared with the natural history in Catterall's Groups I and II, and in Group III the results were only marginally better than those following osteotomy. In Group IV cases, however, where the femoral head was totally involved, the benefit was important, and since these are the cases which carry the worst natural prognosis it is suggested that the use of the method described in such instances must be seriously considered in spite of its social disadvantages. The theoretical implications of the findings are considered, and it is concluded that the benefits of the method cannot be ascribed wholly to the application of the "containment" principle.

Experiments have been performed on rabbits and sheep which demonstrate that pure carbon, in a flexible and filamentous form of great strength, can be used successfully to induce the formation of new tendons. A concept fundamentally different from that underlying the use of other artificial tendon replacements is involved, in which rapidly developing tendon-like tissue is induced to form around the implant. This gradually takes over the function of the implant. The early results in rabbits and the late results in sheep suggest that filamentous carbon may have a place in the replacement of the calcaneal tendon and the collateral ligaments of the knee.

1. The results of treatment have been compared in two unselected series of patients with unstable fractures of the thoraco-lumbar spine accompanied by paraplegia.

2. One group had been treated by conservative or " postural" methods while the others had been subjected to open reduction and internal fixation with double plates.

3. No difference in the amount of neurological recovery could be detected between the two groups but while a number of conservatively treated patients had significant residual spinal deformity and subsequently developed serious pain, this did not occur in any of the patients treated by plating.

4. It is concluded that open reduction and internal fixation are indicated in displaced fractures in the interests of long-term spinal function.

1. The findings in a femoral head obtained at necropsy on a boy aged nine suffering from Perthes' disease are described.

2. The findings revealed that there had been avascular necrosis of the epiphysis followed by revascularisation and healing, and there was evidence to suggest a second episode of infarction.

3. The findings provide strong support for the suggestion that Perthes' disease is the result not of one but of more than one episode of major infarction.

1. Dissection of forty-four developing human hip joints has shown that while the embryonic acetabulum is a deeply set cavity which almost totally encloses the head it gradually becomes more shallow as birth approaches. During the same period the femoral head becomes less globular and at the end of foetal life is almost hemispherical. The cover afforded to the femoral head by the acetabulum also becomes decreased.

2. After birth these trends reverse: the acetabulum becomes deeper again and the femoral head more globular. This process continues throughout childhood.

3. The findings provide a possible explanation for the increased liability to dislocation of the infantile hip.

1. A specially designed splint is described with which it is possible to maintain the reduction of a paralytic dislocation in a child with spina bifida cystica. The results of its use in a series of thirteen cases are recorded.

2. It is suggested that all such children presenting in the first year of life, in whom the power of the flexor and adductor muscle groups is preserved, should be treated initially in this way until the prognosis for the individual can be accurately assessed.

3. The theoretical implications of the findings are discussed.

1. Grafts of joint cartilage from immature lambs were used to repair articular cartilage defects in other lambs and in adult sheep.

2. Stability of these grafts in a functional state was found in most for periods up to fourteen months. Although a limited homograft reaction occurred this did not lead to destruction of the cartilage, even though parts of it were well vascularised.

3. The results suggest that the process of endochondral ossification is associated with the liberation of antigenic material leading to sensitisation of the host. Destruction ofthe cartilage is prevented by an inhibitory action which the matrix appears to exert on the destructive elements themselves and which is itself dependent on the vitality of the chondrocytes.

4. The avascularity of cartilage is not a sufficient explanation for its privileged position in relation to the homograft reaction.

The findings in a child with bilateral congenital dislocation of the hips who died shortly after birth are described. The only significant abnormality present was redundancy of the capsular ligaments and elongation of the ligament of the femoral head. The relationship between the orientation of the femoral neck and of the acetabulum was within normal limits. The significance of these findings in relation to etiology and management are discussed.

1. The source of nutrition of articular cartilage still remains a subject of controversy.

2. Experiments are described in which an attempt to demonstrate the direct transfer of fluid from the subchondral bone has been made using 355 and an autoradiographic technique. These experiments were based on ones originally performed by Ekholm (1951), except that two distinct groups of animals were used : immature rabbits and adult rabbits whose skeletons were mature.

3. The transfer of fluid to the cartilage could be demonstrated only in the immature rabbits.

4. It is suggested that some of the conflicting opinions which have been advanced on this subject stem from a failure to distinguish between mature and immature joint cartilage. Subchondral nutrition is a feature only of the immature animal.

1. Dissections of the newborn child revealed that the psoas muscle is a lateral rotator of the hip in all positions but that this secondary action is much stronger when the limb is abducted.

2. It has also been shown that the iliacus portion of the muscle can contribute towards the completion of abduction movement.

3. An attempt has been made to reconcile these facts with the accepted concept of the action of the muscle in the adult.

4. The clinical significance is discussed.

1. The hypothesis is put forward that the cartilage of a developing epiphysis consists of two separate moieties. There is a superficial zone which from the first is destined to become articular cartilage and is incapable of ossification, whereas the deeper layers are concerned with the actual growth of the epiphysis and will eventually be converted totally to bone.

2. The results of an experiment which support this theory are described. A piece of developing joint cartilage was excised and replaced in its bed upside down. It was found that although the cartilage continued to proliferate at its normal rate, ossification of the original articular layer did not occur, so that there was a considerable increase in the thickness of the excised cartilage.

3. The supporting evidence for the hypothesis is discussed.

1. Experiments have been carried out in lambs to determine the source of nutrition of the joint cartilage of an immature animal. A wedge of bone with its overlying cartilage was removed from the knee joint and then replaced in its original position, so that the bone was infarcted but the cartilage remained in normal relationship with the joint.

2. In these circumstances degeneration of the cartilage occurred and proliferation ceased until revascularisation of the bone was established.

3. It is therefore concluded that growing cartilage derives a significant part of its nutrition from the underlying bone. The possibility that it also receives a contribution from synovial fluid has not been excluded.