Gap formation during controlled motion after flexor tendon repair in zone II: a prospective clinical study.

Intratendinous metal markers were used to study the formation of gaps in flexor digitorum profundus tendon repairs during and after early controlled motion with dynamic flexion traction and to evaluate their significance for results in 34 digits with repairs in zone II. The mean (+/- SD) final repair elongation was 3.2 (+/- 3.6) mm. Linear regression analysis showed a general trend toward an inverse relationship between elongation and clinical results in terms of active interphalangeal joint range of motion, but the correlation was weak, and in the individual case gap formation was a poor predictor of clinical result. Gaps of up to 10 mm were quite compatible with good function. The results indicate that controlled motion is effective in restricting the formation of adhesions associated with gap formation during postoperative immobilization.