The authors hypothesized that extensor tendons in the fingers are subject to the “tension band” principle and that they might be amenable to repair by dorsal-only epitendinous sutures. They performed an in vitro study to assess gapping and rupture following 3 different extensor tendon repair techniques in porcine foot extensor tendons using a curvilinear testing apparatus. A Silfverskiold dorsal-only epitendinous repair was found to be significantly stiffer and more resistant to gapping and rupture than mattress and Kessler core suture techniques.
In contrast to flexor tendon repair techniques, there are relatively few published studies of extensor tendon repair techniques. The authors of this report contend that extensor tendons in the finger are not amenable to repair by both core and epitendinous sutures. Their findings support an epitendinous-only technique in areas where the tendon is flat and close to bone. A combination of core and epitendinous sutures will still provide for a stronger construct and may be feasible without tendon bunching and shortening, particularly in Zone 4 and 5.