[Dislocation of the pisiform bone. A review of the literature].

Dislocation of the pisiform bone is extremely rare. So far, only 25 cases proved by radiographs have been reported. The sturdiness and stability of its ligamentous attachments may explain why dislocations of the pisiform are so rare. Often the dislocation is the result of direct trauma to the palmar and ulnar aspect of the wrist and less frequently due to indirect force or forceful muscular contraction. Dislocation of the pisiform bone occurs predominantly in young and active males. Usually, the pisiform is dislocated proximally or distally. The diagnosis is made by plain radiography. Operative treatment with pisiform excision and meticulous reapproximation of the attached soft-tissue structures yielded the most reliable results with preservation of wrist-flexion strength. Thus, although being very heterogenous with regard to mechanism of injury and displacement, pisiform dislocations should receive uniform treatment to obtain predictable results.