1. A case of spontaneous fracture of a first rib is described.

2. Its evolution from a previously intact rib through the stage of a "linear" crack to pseudarthrosis has been traced.

3. An older pseudarthrosis was present on the opposite side.

4. Alderson's observation is confirmed—that the breach in the rib is acquired. There is no need to suppose a developmental anomaly of ossification, even in a bilateral case.

Arthroplasty, with normal or nearly normal reposition, is possible in most old congenital dislocations of the hip in young adults. Reposition is possible even in very high dislocation, but it is difficult or impossible in aged patients and when arthritic changes have taken place. The reduction equalises the length of the extremities in unilateral cases, but makes operation on both sides necessary in bilateral cases. Post-operative complications may be largely avoided by a good technique and careful post-operative treatment. Stability is good, and consequently the limp is generally reduced. Mobility is as a rule sufficient, though often less than before operation when the hip was normally or excessively mobile. Pain is very often relieved or greatly reduced, but walking is generally limited. Even if the radiographic appearance of the hip is almost normal, the functional result may be imperfect.

This assessment is probably pessimistic, for two reasons: first, patients operated on are still improving; second, the improved technique of the later operations should give better results. Nevertheless, arthroplasty with reduction should be proposed to patients only suffering severe functional disability.

Sprung back is one of the commonest causes of low back pain. Its characteristic features are described. It is caused by rupture of the posterior ligaments of the spine, including sometimes the posterior longitudinal ligament and annulus fibrosus. The manner in which it is produced and its mechanical effects are discussed in detail.

Twelve cases of congenital fusion of the lunate and triquetral bones have been found in South African Bantu patients. The fusion occurs in four types, an incomplete "pseudarthrosis," bony fusion with a dividing notch at one or both surfaces, or as a complete compound bone with or without other carpal anomalies.

The suggestion favoured is that this fusion represents the persistence of a primitive characteristic in African (negro) peoples.

1 . Twenty-two cases of transplantation of the tibialis anterior for relapsed club-foot have been reviewed. Results were good in sixteen cases, fair in two and bad in four.

2. The operation and routine treatment are described.

3. The reasons for the four failures are discussed.

4. It is concluded that the operation is well worth while, and will often avoid the need for bony stabilisation at a later date.

1. The evolution of the skeletal changes in chondro-osteo-dystrophy is described, and typical radiographs of patients observed into late adolescence are shown.

2. The etiology of the condition is discussed.

A case is described of bilateral traumatic chylothorax after complete dislocation of the thoracic spine. An explanation is advanced for the delayed, sudden onset of symptoms due to the chylothorax in this and other cases.

1. A case is reported of traumatic dislocation of the shoulder joint complicated by rupture of the axillary artery and vein and complete brachial plexus palsy. Whether the rupture occurred at the time of injury or during reduction is not known.

2. Despite a delay of five weeks before operative treatment was undertaken the usefulness of the arm was preserved.

3. After rupture of the axillary artery at this level an adequate collateral circulation is rapidly established in a healthy young adult.

4. The case illustrates the importance of careful examination of the peripheral nervous and vascular systems before and after reduction of a dislocated shoulder.

1 . Two patients with monomelic bone and joint changes in neurofibromatosis have been described.

2. The joint changes in neurofibromatosis include dysplasias, sclerosis of the articulating bone ends and secondary osteoarthritis.

1. A case of flake fracture of the talus progressing to osteochondritis dissecans is reported.

2. The relationship between direct injury and the onset of the lesion is noted.

3. The sequence of events was observed radiographically and clinically for two years from the date of the original injury.

A case is described of malignant osteoclastoma of the lower end of the femur in which death occurred from pulmonary metastases. The history was short and there was no interference with the primary growth, treatment being confined to disarticulation at the hip. Reasons are given for considering this neoplasm a malignant osteoclastoma rather than an osteogenic sarcoma, and the question of nomenclature is discussed.

1. A series of twenty-one cases of synovial tumour is tabled and the histological appearances are discussed.

2. The characteristic histological forms, (a) mucin formation, (b) synovial spaces, (c) endothelial and "gland" spaces and (d) epithelium-like tissue, are described.

3. These all arise by differentiation of connective tissue cells which occur throughout the connective tissue part of the limbs.

4. Though more commonly found in regions where synovial membrane is present, they are not confined to such special areas.

5. The tumours are classified on a histological and not a histogenetic basis.