Abstract
1. Forty-eight cases of causalgia are reviewed and the clinical features are briefly described.
2. Multiple nerve injuries are common and the pain is often associated with all the injured nerves. In the upper limb there was always an incomplete lesion of the lower trunk or medial cord of the brachial plexus, or of the median nerve. In the lower limb there was always an incomplete lesion of the medial popliteal division of the sciatic, the medial popliteal, or the posterior tibial nerve. These nerves carry most of the sympathetic fibres to the hand and foot. With two exceptions all the nerve lesions were at or above the level of the knee or elbow.
3. Sympathectomy gives marked relief of pain in most cases of causalgia. Prompt treatment is essential to prevent the crippling deformities which follow prolonged voluntary immobilisation of the painful limb. The results of preganglionic are superior to those of postganglionic sympathectomy.
4. The possible pain pathways are discussed, and an explanation is offered for the successful results of sympathectomy in the treatment of causalgia.