Review Question - QID 211215

A 21-year-old right hand dominant male was slicing an avocado in his New York City apartment when he lacerated his left ring finger. At the time of injury he was unable to flex the interphalangeal joints of the finger. He underwent surgical repair of the injured flexor tendon, which was shortened by 12 mm, but repaired with 8 core-suture in a cruciate pattern. He was placed on an early-active range of motion protocol and quickly regained his motion. Three months after repair, the patient continues to complain of difficulty actively bringing his middle and small finger into his palm as seen in Figure A. He otherwise has full passive motion. What factor is precipitating the discrepancy between his active and passive motion?