Metacarpophalangeal subluxation: locked finger.

The so-called locked finger is a rarely reported condition that can be easily recognized when its typical picture is borne in mind: painful locking of a finger, making it impossible to fully extend the metacarpophalangeal joint, and a lateral displacement of the extensor tendon at this level. Radiological findings may include abnormal shape of the metacarpal head, free intra-articular bodies, sesamoid bones at the volar plate level and degenerative changes in the metacarpophalangeal joint. There is consistently a previous history of repeated light manual effort. This condition generally affects men, aged 50 or older. Two of the three cases presented (three of the four affected fingers) were successfully treated by means of gentle manipulation under regional nerve blocking. The patient who refused treatment remains with a painless locked finger 1 year later. There has been no recurrence with either of the two manipulated patients (three fingers).