1. A study of 2,200 patients receiving electro-convulsive therapy showed that fifty-three sustained fractures or dislocations—an incidence of 2·4 per cent. Of the fifty-three injuries, twenty-one occurred in the spine, fifteen in the neck of femur, fifteen in the upper end of humerus, one in the coracoid process; one dislocated jaw required anaesthesia for its reduction (other cases of transient dislocation of the jaw are excluded).

2. The incidence, site, and type of spinal fractures are recorded, and the relation of the fracture to the first convulsion is noted. No late changes were found in the spines of patients examined two years or more after treatment. A neutral position of the spine during the convulsion is believed to diminish the risk of fracture.

3. Fracture of the neck of the femur is a serious injury in these patients. In one case the injury was bilateral.

4. The fifteen cases of fracture-dislocation of the upper humerus are analysed. They included two cases of posterior dislocation of the humeral head; the possible mechanism of this is explained and a method of prevention suggested.

5. Fifty-three patients with chronic epilepsy with psychosis were examined. Four cases of fractured spine were discovered. The site of fracture was different from that of fractures caused by convulsive therapy and a reason for this is suggested. The type and mechanism of the fracture are similar in the two groups.