Changes in digital flexor tendon mechanics after endoscopic and open carpal tunnel releases in cadaver wrists

Digital flexor tendon excursion due to isolated wrist motion was measured i n 5 cadaver wrists. Five sequential experimental conditions were tested: (1 ) intact wrists, (2) after single-incision endoscopic carpal tunnel release , (3) after addition of a distal endoscopic portal, (4) after conversion to an open palm incision, and (5) after suturing of the palm incision. Combin ed tendon excursion increased 27.8% after 1-incision and 29.7% after 2-inci sion endoscopic release; both increases were significant. A further increas e in combined excursion to 43.4% over the value in intact wrists was measur ed after conversion to an open palm incision. Combined flexor tendon excurs ion after open release was significantly greater than excursion after eithe r type of endoscopic release. Increases in excursion were also significant when flexor digitorum superficialis and flexor digitorum profundus tendons were considered separately. Excursion did not change significantly after sk in suturing. These Findings suggest that digital flexor tendon mechanics ar e closer to normal after endoscopic carpal tunnel release than after open r elease. It remains to be shown whether the difference is an advantage of en doscopic release over open release in the clinical setting. Copyright (C) 2 000 by the American Society for Surgery of the Hand.