In fifty-two knees with spontaneous osteonecrosis the diagnosis was based on a subchondral transradiancy in the weight-bearing surface of the medial femoral condyle. Strontium-85 scintimetry showed a unique pattern, indicating a lively repair reaction by localised high values. Thirteen of fifteen knees followed between two and twenty-three years developed osteoarthritis. The prognosis was based on the size of the transradiancy and the focality of the lesion as determined by scintimetry. It is suggested that scintimetry permits differentiation between primary osteoarthritis and arthritis secondary to osteonecrosis.

1. The long-term results of 740 European patients suffering from spinal tuberculosis and treated without and with specific anti-tuberculous drugs have been surveyed.

2. The results of treatment by conservative methods and by conventional surgical methods have been compared in the two periods. The attainment of spinal stability as judged by serial examination of radiographs was the main criterion in assessing healing.

3. Although the results of conventional treatment have improved since the advent of chemotherapy, the credit is mainly due to the influence of more frequently and more expertly applied operations.

4. With chemotherapy the well tried medical and surgical procedures produce stable spines in three-quarters of cases. With early operation on the lesion the results are better and more quickly obtained. Of eighty spines on which focal surgery was performed during the past twelve years before the lesions had become extensive, seventy-seven (9·62 per cent) healed by bone. The average duration of hospitalisation after such operation was four and a half months. No patient has had to be readmitted.

5. The difficulties and possible dangers of these methods must be emphasised. The operations are difficult and dangerous when the lesions have been allowed to get out of hand and become unduly extensive. They are contra-indicated in cases where there is very marked deformity.

6. Training in special techniques of operation is necessary. Duplicated drainage of the hemithorax after thoracotomy is essential, and skilled after-care is important if good results are to be obtained.

1. Thirteen cases of congenital pseudarthrosis of the clavicle conforming to the classical picture are presented, together with five cases of pseudarthrosis occurring for various other reasons, and nine cases of congenital pseudarthrosis that form a special group because there was a strong family history.

2. Treatment, if desired by the patient, is easy, but should be deferred until the age of four or five years.

3. The etiology remains obscure. Our embryological study does not support the theory that the clavicle normally develops from two ossification centres that may fail to coalesce. Although in thirteen of our patients there was no family history of pseudarthrosis, there was another group of nine patients who presented a strong family history, and it seems certain that in some instances congenital pseudarthrosis of the clavicle can be transmitted genetically.

1. Thirty-three cases of congenital pseudarthrosis of the clavicle are presented.

2. The lesions all occurred in the right clavicle and are thought to be due to abnormal intrauterine development rather than non-union of birth fractures.

3. Methods of treatment are reviewed. Excision and bone grafting is favoured.

1. Four cases of ochronotic arthropathy have been studied and the related literature has been reviewed.

2. Ochronotic arthropathy is a rare condition resulting from an inborn error of metabolism occurring as a Mendelian recessive characteristic. Its incidence, however, may have been underestimated.

3. Problems of differential diagnosis are discussed and it is suggested that more widespread screening should be undertaken in order to assess the true incidence of the condition.

1. Using the incidence of hip fracture as an indication of senile osteoporosis, the occurrence of this disease is found to vary greatly in different racial groups. The highest reported incidence is in Sweden, followed by Britain, Hong Kong Chinese, Singapore Chinese and South African Bantu, in that order. Likewise, the sex incidence varies, women outnumbering men in Sweden and Britain, men exceeding women in Singapore; an equal sex incidence is found in Hong Kong.

2. In all races and in both sexes the incidence is more closely related to age than any other factor, a progressive increase being noted after forty-five. Ageing is clearly the dominant etiological factor, but this does not explain the different racial incidence. These differences cannot be attributed to hormonal state or to the dietary intake of calcium, but do accord in general with the living standards of the different countries and the degree of physical activity undertaken by the different populations and sexes.

3. Hereditary factors may play a part, but further geographical study of the incidence of senile osteoporosis is necessary before the relative importance of inheritance and environment can be assessed.

1. Sixty-eight crush fractures of the articular surface of the lateral tibial condyle have been analysed.

2. Follow-up examination at a minimum of three years after injury was carried out in all cases.

3. The only factors which appeared to influence the results were the extent of the original depression, and if this was severe, the degree of restoration obtained by the treatment. Prolonged plaster fixation was avoided.

4. At review, no patient complained of symptoms which were attributable to damage to ligaments or menisci and no patient had symptoms of late onset.

5. The results suggest that there is nothing to be gained by open reduction if the lateral condyle is depressed by less than 10 millimetres, as conservative treatment gives good results. If the depression is more severe, however, a good result can only be assured if the articular surface is successfully reconstituted, but this is sometimes difficult to achieve. It is not possible to reconstitute the surface by non-operative means.

1. Experience with the McLaurin swivel walker for children with bilateral phocomelia of the lower limbs is described.

2. Modifications to the prosthesis and the method of fitting in stages are recorded.

1. Fifteen patients who had had osteomyelitis of the lower femur or upper tibia during infancy have been studied. The cases of four patients showing particular features of the disease are presented in detail and the remainder are summarised.

2. It is suggested that damage to the epiphysis may be due to an abscess, or to ischaemia following occlusion of the blood supply. In the latter instance the prognosis may be better.

3. In the early stages the radiographic appearances may be deceptive, suggesting that damage to the epiphysis is irreparable.

4. Significant recovery of the epiphysis may occur in some patients after a delay of several years. This, together with the often good function which is preserved at the joint, should deter the surgeon from early destructive operation on the limb.

5. Deformity, which was present to some extent in all cases, appeared early and was not well controlled by conservative treatment. Operations were performed in twelve patients.

6. Shortening of the limb occurred in all patients and in some it was severe.

1. A survey of genetic and other etiological factors has been carried out in 589 index patients with congenital dislocation of the hip and their families, with special investigation of acetabular dysplasia, familial joint laxity and a comparison of neonatal and late-diagnosis cases.

2. It is believed that there are two etiological groups with congenital dislocation of the hip, i) a group with acetabular dysplasia which is inherited as a multiple gene system and is responsible for a high proportion of cases diagnosed late, and ii) a group with joint laxity which is responsible for a high proportion of neonatal cases.

3. Evidence is presented to show that acetabular dysplasia is a separate heritable system in some families.

4. Other findings relating to the genetic aspects of the survey are summarised.

Two cases of skeletal amyloidosis are described. In one the disease existed for many years, progressively destroying several vertebral bodies. There was no evidence of chronic infection, myelomatosis or cancer. In the other case myelomatosis was the primary disease but the first manifestation was a cystic tumour of the humerus. Not until several years later did typical bone lesions and Bence-Jones protein reveal the true nature of the disease.

1. Two cases of syphilitic involvement of the spinal column are described, illustrating the presentation and pathology of the disease.

2. The possibility of increased incidence of syphilitic disorders of bone and joint is considered in the light of recent statistics, and the need for awareness of the disease in its various forms is emphasised.

3. The problems of diagnosis are discussed.

1. A diagnostic procedure is described which is specific for fat embolism. It allows identification of the pathological fat globules On a stained slide.

2. The amount of pathological fat can be estimated by comparing the serum triglyceride levels before and after filtration.

3. The method is simple, reproducible and inexpensive.

1. A bilateral case of chronic intermittent ischaemia of the soleus muscle within its fascial compartment is described in a dental surgeon aged twenty-seven.

2. Symptoms were promptly relieved by decompression.

3. The mechanism of the condition is compared with that of the anterior tibial syndrome.

A case of malignant transformation of a benign chondroblastoma of the tibia in a fifteen-year-old boy is reported. The tumour was not irradiated at any time during the course of the disease. The tumour showed a typical appearance of benign chondroblastoma at the first operation. It recurred repeatedly after curettage, and finally emerged as a highly malignant undifferentiated sarcoma. In spite of amputation the patient died nine years after the onset of the disease with an enlarged liver and inguinal lymph nodes.

The morphological changes in bone and articular cartilage destruction have been described in sixteen consecutive cases of rheumatoid arthritis in which biopsy material was obtained during synovectomy of the knee. The following observations were made.

1. Bone and cartilage is replaced by fibrous granulation tissue which proliferates from periosteal and perichondrial fibroblasts.

2. These proliferative changes are distinct from the chronic synovitis of rheumatoid disease, but a chronic synovitis is necessary for them to appear.

3. Synovectomy does not remove the cells replacing bone and cartilage but its performance in some ways leads to their regression.

1. An anomalous muscle belly of flexor digitorum superficialis (sublimis) presenting as an aching swelling and simulating a ganglion is reported.

2. It is suggested that this could be an atavastic muscle belly of flexor digitorum superficialis.