Metacarpal Neck Osteochondroma: An Atypical Cause of "Trigger Finger".

"Locking" of the digits is a relatively common patient complaint in hand surgery. Typically, this phenomenon arises from either triggering of tendons at the A1 pulley or subluxation of tendons around the metacarpal head. Although trigger digit and sagittal band injury comprise most diagnoses, clinicians must be aware of rarer entities that alter the underlying osseous anatomy and predispose the digits to "locking." Here, we present a case of metacarpal neck osteochondroma causing subluxation of the index metacarpophalangeal joint radial collateral ligament.