Three complications of untreated partial laceration of flexor tendon--entrapment, rupture, and triggering.

Three patients developed complications as a result of unrepaired and untreated partial laceration of flexor tendons. In one, narrowly based flaps of the tendons became entrapped in a rent in the flexor tendon sheath. In a second, delayed rupture of the flexor pollicis longus occurred when force was applied to the tendon 2 weeks after the injury. In the third, triggering of the thumb occurred 2 months after a laceration which passed through the annular pulley into the tendon.