Orthopaedic Hand Trauma CH35

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CHAPTER 35  | Jersey Finger

Figure 35.2  Mechanism of injury for jersey finger.

involved in 75% of FDP avulsions. The higher susceptibility of the ring finger to this injury is related to several anatomic differences. It has been demonstrated that the ring finger has the least independent motion of all the digits. Also the insertion of the ring finger FDP is weaker than the FDP insertion of the long finger. Finally, the ring finger extends farther than the other digits during full grip and absorbs the most force during pull-away testing, making it prone to avulsion.

EVALUATION

■ ■ Presentation —Patients often present with acute pain and swelling over the volar surface of the distal finger. The point of maximal tenderness may indicate the location of the avulsed tendon. ■ ■ Physical Examination —On examination, the affected finger lies in ex- tension relative to other fingers in resting position ( Figure 35.3 ). Patients are unable to actively flex the DIP joint when asked to make a fist. Often

Figure 35.3  Clinic photograph of jersey finger injury with ring finger held in extension.