Bowstringing as a complication of trigger finger release.

Bowstringing is a rare complication of trigger finger release caused by excessive loss of the proximal pulleys. As the flexor tendon moves away from the center of rotation of the metacarpophalangeal joint, the flexion moment arm is increased. Thus the flexors gain an increased mechanical advantage over the extensors resulting in limited digital extension. We describe a case of severe bowstringing progressing over 9 years resulting in pain, altered digital function, and loss of full extension.