Five knees with congenital dislocation were explored. The cruciate ligaments were found to be absent or hypoplastic. The results obtained by reconstructing an anterior cruciate ligament appear to be good. On the basis of dissections of foetal knees we believe that the cruciate ligaments are the main structures preventing an anterior dislocation of the knee in early foetal life; this deviation from the adult pattern is due to the bony configuration of the foetal knee. We therefore postulate that the basic defect in congenital dislocation of the knee is an absence or hypoplasia of the cruciate ligaments.

1. An unusual muscle anomaly found during an operation for a severe club foot is recorded.

2. This muscle fitted the description of the flexor accessoreus longus and may add support to the phylogenetic theories of development of the long flexor muscles suggested by Wood Jones.

1. Injuries to the atlas and axis may occur at any age. They are usually not fatal.

2. In children spontaneous rotatory dislocation is the commonest type of lesion. In adults fracture of the odontoid process is more likely.

3. The spinal cord is often undamaged. In some cases complicated by cord damage the neurological disturbance is caused by an associated injury to the lower cervical spine.

4. Spinal cord damage may be immediate or delayed.

5. In cases of incomplete cord lesion there may be recovery of function after reduction of the displacement or without such reduction.

6. Diagnosis rests on the history and physical signs, and radiographic findings. Radiographs of this area require careful interpretation, and special radiographic techniques may he necessary. A normal radiograph does not necessarily exclude the possibility of atlanto-axial injury.

7. Though many patients would survive without treatment the initial discomfort and danger of complications demand that adequate protection be provided. In relatively minor injuries and in old people protection by a plaster collar may be sufficient. In some cases it is justifiable to undertake manipulation and apply a plaster. Cases with severe displacement require traction, preferably by skull calipers. Recurrent displacement, instability, and cord signs demand operative reduction and fusion. Satisfactory fusion of the atlas and axis alone is feasible, and good function is preserved. More extensive fusion of the cervical spine is seldom necessary.