Compression of the deep palmar branch of the ulnar nerve: clinical and electromyographic findings after a new method of decompression.

Five cases of compression of the deep palmar branch of the ulnar nerve were operated upon and the hiatus released by subperiosteal removal of the pisiform bone. The clinical and electromyographical results after a minimum follow-up of eight months showed an improvement in all cases. The authors stress the importance of accurate electromyographic examination for a correct preoperative diagnosis.