1. Dislocation of the pisiform is rare. Volar pain in the wrist with the sensation of "something going out of place" may inudicate a dislocating pisiform.
2. Dislocation of the pisiform is caused either by muscular violence or direct injury.
3. The pisiform is a regressive structure in man, bit forms the heel of the hand in the non-aquatic vertebrate.
4. In acute cases of dislocation which do not respond to splinting, and in chronic cases, surgical excision is indicated. Removal of the bone in no way interferes with the normal function of the wrist.