Morphological Changes in Flexor Tendon Adhesion Following Early Exercise After Tendon Repair

Abstract

Summary: Adhesion is a common complication following surgical repair of flexor tendons, resulting in the restriction of tendon gliding. We investigated the effect of early exercise on adhesion formation. To create an adhesion model, the proximal region of the second phalanx of the third toe in 4-month-old White Leghorn chickens was cut. The gliding side of the flexor digitorum profundus was hemiresected and the bony floor was crushed to enhance adhesion formation. The resected area was fixed in an extended position for 1, 2, or 3 weeks. Following 1, 2, or 3 weeks of active exercise, the chickens were sacrificed and morphological changes in the adhesions were assessed. In the 1- and 2-week fixed groups, 1, 2, or 3 weeks of active exercise resulted in mesotenon-like adhesion that was elastic and had no effect on tendon gliding. However, in the 3-week fixed group, a mature adhesion remained with limited change and tendon gliding was inhibited even after 3 weeks of active exercise. Thus, we concluded that adhesions become more elastic with early exercise within 2 weeks after tendon repair, but that adhesions following tendon repair tend not to show any further elastic changes when exercise is started 3 weeks after the repair.