1. The various surgical procedures in common use for the treatment of the osteoarthritic hip are briefly reviewed and compared with the operation of replacement of both the acetabulum and head of the femur by a metal prosthesis, that is, a complete artificial hip joint.

2. The development, description and technique of insertion of this artificial hip joint are given in detail.

3. The results of the first fifty cases of this operation show a success rate of over 90 per cent. The few failures are analysed in detail. The revision procedure has been the insertion of another artificial hip joint.

4. The essential details necessary for success are stressed and the indications and aims of the operation given.

A method of intra-articular arthrodesis of the hip is described in which fixation is obtained with a lag-screw. Two main advantages are claimed: first, that it is a compression arthrodesis and gives early bony fusion; and second, that it gives adequate internal fixation in most cases so that the disadvantages of a plaster hip spica are avoided, and the patient may walk with crutches two or three weeks after the operation.

The results were satisfactory in forty-seven of the first fifty cases in which this method of arthrodesis was employed. There were two post-operative deaths and one failure to secure fusion in a case of massive necrosis of the femoral head.