In jersey finger injuries, which action is compromised due to avulsion of the flexor digitorum profundus tendon?

Study for the NBCOT Hand Injuries and Intervention Test. Prepare with flashcards and multiple choice questions, each question offers hints and explanations. Get ready for success!

Multiple Choice

In jersey finger injuries, which action is compromised due to avulsion of the flexor digitorum profundus tendon?

The key idea is that flexor digitorum profundus (FDP) straight flexes the distal interphalangeal joint. When the FDP tendon avulses from the distal phalanx as in a jersey finger, the force needed to actively bend the DIP is lost, so the finger can no longer actively flex at the DIP. The rest of the finger’s movements—PIP flexion mainly by the flexor digitorum superficialis and DIP extension by the extensor mechanism—are not broken by this injury. Abducting the thumb uses different muscles entirely, so that action isn’t affected.

The key idea is that flexor digitorum profundus (FDP) straight flexes the distal interphalangeal joint. When the FDP tendon avulses from the distal phalanx as in a jersey finger, the force needed to actively bend the DIP is lost, so the finger can no longer actively flex at the DIP. The rest of the finger’s movements—PIP flexion mainly by the flexor digitorum superficialis and DIP extension by the extensor mechanism—are not broken by this injury. Abducting the thumb uses different muscles entirely, so that action isn’t affected.

More practice questions