1. The histories of 149 patients, coming to the Hospital for Sick Children within the first three years of life with congenital dislocation of the hip (191 dislocated hips), and treated by conservative methods, have been reviewed.

2. The patients with unilateral dislocations (107) have been divided into three groups, according to the angle of slope of the opposite acetabulum. This angle was measured on the first radiograph and related to the mean value for age and sex.

3. The opposite hip was classed as "normal" if the acetabular angle was below or within one standard deviation above the mean for sex and age; as "moderately shallow" if it was between one and two standard deviations above the mean; and as "shallow" if it was over two standard deviations above the mean. This grouping was found to have a direct bearing on the results of conservative treatment in unilateral cases. a) Those with "normal" opposite acetabula–accounting for most of the unilateral cases–responded well. b) Those with "moderately shallow" opposite acetabula responded variably. c) The group with "shallow" opposite acetabula usually failed to respond.

4. Most bilateral dislocations behaved as unilateral dislocations with shallow opposite hips.

5. Additional factors influencing the response to conservative treatment–sex, age at first attendance, family history, fragmentation of the femoral epiphysis and eccentric reduction–are discussed.

1. The results of treatment of 134 patients with congenital dislocation of 167 hips are reviewed.

2. Late diagnosis is still a major problem.

3. Subluxations rarely give rise to poor results, but in dislocations first treated over the age of five years there is a one-in-three risk of failure.

4. Manipulative reduction is successful less often than reduction on a frame and carries a higher risk of avascular necrosis.

5. Closed reduction on a frame was satisfactory in 58 per cent of patients under the age of three years, and can succeed up to the age of five.

6. Open reduction was required in 20 per cent of cases under the age of three, and can be used successfully up to the age of six.

7. Seven anatomical barriers to closed reduction have been recognised and two or more are commonly found in one hip when open reduction is performed.

8. The acetabular roof may fail to develop after reduction, especially if this is delayed. A C.E. angle of under 20 degrees does not necessarily forebode this, unless measured on an arthrograph. Sclerosis of a sloping acetabular roof is an indication for operation. Acetabuloplasty is the proper operation for a sloping acetabulum and can be done successfully up to the age of twelve. Over this age, a shelf operation should be performed; this is appropriate also in younger patients in whom the curvature of the acetabulum is normal but does not extend far enough laterally. These operations were required in 38 per cent of hips treated in patients under the age of three, and in 64 per cent over this age. There is a one-in-three risk of avascular necrosis when acetabular reconstruction is done in patients under three.

9. Anteversion, if excessive, should be corrected by subtrochanteric osteotomy, and any valgus of the femoral neck should be corrected simultaneously.

10. Unilateral dislocations in patients over the age of six are best treated by Colonna's operation. In our few bilateral cases over this age our results have been disappointing.

11. Avascular necrosis is less common but more serious when it occurs over the age of three. Manipulative reduction and the use of frog-leg plasters are two avoidable factors which appear to increase its incidence. The more serious degrees are accompanied by stiffness of the hip, and when this sign is present weight bearing should be avoided.

12. Prolonged, though rarely permanent, limitation of movement occurs in some 10 per cent of cases. In a few, operative correction was required.

1. Attention is drawn to the powers of resistance of the growing ends of bones in suppurative pyogenic arthritis of the knee and hip in infancy.

2. It is emphasised that a translucent zone in the radiograph does not necessarily mean that this part of the bone, epiphysial cartilage or plate is destroyed.

3. Diagnostic criteria are described to confirm that cartilage or decalcified bone has survived the infection in the knee joint.

4. The prognosis for the knee joint is discussed.

5. The hip joint presents greater difficulties in diagnosis and greater issues are at stake. It is recommended therefore that the hip joint be manipulated or explored if the radiograph and the physical signs suggest that destruction of the joint has either caused dislocation or has so damaged it that dislocation is likely to occur in the future. In favourable cases stability may be restored to the hip. In the others a diagnosis of irreparable destruction is established and the surgeon is satisfied that an opportunity to help the patient has not been lost.

An inquiry was made of ninety-seven patients with recurrent dislocation of the patella and forty patients with recurrent dislocation of the shoulder to see how often they had a relative similarly affected, and also how often such dislocation is associated with, and perhaps caused by, familial joint laxity.

Ten of those with recurrent dislocation of the patella and two of those with recurrent dislocation of the shoulder were found to have a near relative with a similar dislocation. Familial joint laxity was found in two of the ten families with more than one member affected by recurrent patellar dislocation, and in both those with more than one member with recurrent dislocation of the shoulder. Familial joint laxity was also found in two out of twenty patients with recurrent dislocation of the patella who had no family history of similar dislocation; but in none out of twenty patients with recurrent dislocation of the shoulder and who had no family history of similar dislocation.

Familial joint laxity may be the only cause of recurrent dislocation of the shoulder occurring in more than one member of the family. But there are other, as yet undefined, causes of familial recurrent dislocation of the patella.

A case of simultaneous posterior dislocation of both shoulders, occurring in an epileptiform fit, is described. Manipulative reduction succeeded after five days, and full function was gained.

1. The nature of flexion contractures of the knee joint is discussed.

2. It is suggested that division of the anterior cruciate ligament will help in the correction of the deformity when conservative methods have failed.

3. The results of the treatment of twelve such knees are mentioned and illustrative cases are described.

4. It must be emphasised that this method of treatment should be undertaken only when conservative methods have failed.

1. Three new cases of neonatal sciatic palsy are reported in twins. They received identical treatment after birth; in the case of the first two for identical difficulties occurring after delivery. In twins there is a greater liability to neonatal shock and so a greater incidence of umbilical injections.

2. The clinical evidence and the necropsy findings in Case 3 support the hypothesis that intra-arterial thrombosis is caused by the injection of an analeptic into the umbilical artery.

3. The clinical picture is described, with a discussion on the pathology, treatment and the reason for recovery in some cases.

A case of synovial sarcoma of the humerus is described. The histological features were of an undifferentiated character and the tumour arose in the foetus.

1. Pathological hallux valgus may be differentiated from an increase in the normal valgus alignment of the great toe by the relationship to each other of the articular surfaces of the first metatarso-phalangeal joint; these are congruous in the normal joint, but displaced on each other in the pathological.

2. The earliest change is lateral deviation of the proximal phalanx on the metatarsal head, which may progress rapidly to subluxation.

3. Subluxation is an early change in a high proportion of cases, and is frequently present when the patient is first seen in adolescence.

4. Once subluxation has occurred progression of the deformity is likely.

5. Metatarsus primus varus and hallux valgus increase pari passu. There is not enough evidence to be certain which of these is the primary change, but such as there is suggests that lateral deviation of the great toe occurs first, and increase in the intermetatarsal angle is secondary to this.

6. It is suggested that hallux valgus should be regarded primarily and fundamentally as a subluxation, or tendency to subluxation, of the first metatarso-phalangeal joint.

1. An operation suitable for the correction of hallux valgus in adolescents is described.

2. The results of thirty-three operations performed in children between the ages of nine and eighteen years are analysed.

3. Twenty-six operations are considered to have produced a good result, four a moderate result, and three a poor result.

4. It is suggested that the operation is best performed between the ages of eleven and fifteen years.

Two cases of neuropathic joints in diabetes mellitus are described. The condition, though rare, must be kept in mind in diabetes with neuropathy. With proper control of the diabetes and supportive measures to the joints the prognosis is relatively good.

Four cases of carpo-metacarpal dislocation are described. In one case all five metacarpals of one hand were involved.

1. Fifty-nine patients with fractures of the medial epicondyle of the humerus have been reviewed, of whom more than one-third also had a dislocation of the elbow.

2. The final disability has been shown to be very slight. Non-union occurs very often with conservative treatment, but gives no disability. Union can be obtained by fixation with a Pidcock pin.

3. Operative treatment is advised only when the fragment is included in the joint. It is suggested that the best position of the elbow in patients treated conservatively is about 60 degrees below the right angle.

1. Two cases of lateral dislocation of the radio-humeral joint with greenstick fracture of the upper end of the ulna are described.

2. One case was complicated by a radial nerve lesion.

3. Treatment was by reduction under general anaesthesia and resting the elbow in a collar and cuff sling. Full recovery was present in six weeks.

1. Pain in the elbow in javelin throwers is a common complaint.

2. The commonest type is caused by recurrent strain of the medial ligament. It develops in individuals who employ an incorrect throwing technique. The symptoms are cumulative, increasing with throwing and decreasing and resolving with rest. Treatment consists in improving the throwing technique. Local anaesthetic injected into the tender area produces complete but temporary relief. Hydrocortisone may produce partial or complete relief.

3. A second type of "javelin elbow" occurs in expert throwers and is the result of hyperextension of the elbow at the end of the throw, causing an injury to the tip of the olecranon. The symptoms are the result of a single throw or "mal-throw" and are completely disabling. They resolve with rest but tend to recur. If the tip of the olecranon is fractured excision of the fragment completely relieves the symptoms.

1. Sixteen injected specimens of human femoral heads and necks, in which a nail or screw had been inserted, were examined.

2. The possibility exists that the fixing agent may interfere with the blood supply of the femoral head. The likelihood of this occurrence is not great.

3. The position of the fixing agent in which vascular damage is least likely is the central area or "neutral zone" of the femoral neck and head.

1. Compression forces are mainly absorbed by the vertebral body. The nucleus pulposus, being liquid, is incompressible. The tense annulus bulges very little. On compression the vertebral end-plate bulges and blood is forced out of the cancellous bone of the vertebral body into the perivertebral sinuses. This appears to be the normal energy-dissipating mechanism on compression.

2. The normal disc is very resistant to compression. The nucleus pulposus does not alter in shape or position on compression or flexion. It plays no active part in producing a disc prolapse. On compression the vertebral body always breaks before the normal disc gives way. The vertebral end-plate bulges and then breaks, leading to a vertical fracture. If the nucleus pulposus has lost its turgor there is abnormal mobility between the vertebral bodies. On very gentle compression or flexion movement the annulus protrudes on the concave aspect–not on the convex side as has been supposed.

3. Disc prolapse consists primarily of annulus; it occurs only if the nucleus pulposus has lost its turgor. It then occurs very easily as the annulus now bulges like a flat tyre.

4. I have never succeeded in producing rupture of normal spinal ligaments by hyperextension or hyperflexion. Before rupture occurs the bone sustains a compression fracture. On the other hand horizontal shear, and particularly rotation forces, can easily cause ligamentous rupture and dislocation.

5. A combination of rotation and compression can produce almost every variety of spinal injury. In the cervical region subluxation with spontaneous reduction can be easily produced by rotation. If disc turgor is impaired this may occur with an intact anterior longitudinal ligament and explains those cases of tetraplegia without radiological changes or a torn anterior longitudinal ligament. The anterior longitudinal ligament can easily be ruptured by a rotation force and in my experience the so-called hyperextension and hyperflexion injuries are really rotation injuries.

6. Hyperflexion of the cervical spine or upper thoracic spine is an anatomical impossibility. In all spinal dislocations a body fracture may or may not occur with the dislocation, depending upon the degree of associated compression. In general, rotation forces produce dislocations, whereas compression forces produce fractures.

1. The pattern of tritiated thymidine labelling in the cells of the epiphysial cartilage and metaphysis of the tibia in the rat is described for intervals of one hour to twenty-eight days after injection.

2. The region of dividing cells is defined and evidence given for a zone of reserve cells at the top of the cartilage columns.

3. The difficulties of quantitative grain count studies are discussed, and some approximate values are given for the generation time and mitotic cycle periods of the cartilage plate cells.

4. Some further evidence is given about the life cycles of the osteoblast and the osteoclast.