gms | German Medical Science

Objectives/Interrogation: Early active mobilization (EAM) is rarely performed after tendon grafting because of healing process of grafted tendon and weakness of junction between the distal end of the graft and the base of distal phalanx. We evaluated the outcomes of EAM after flexor tendon grafting using extrasynovial tendons.

Methods: Between 2008 and 2017, the flexor digitorum profundus (FDP) tendons of seven digits in seven patients were reconstructed using extrasynovial tendons, including the palmaris longus, plantaris, and extensor digitorum longus via single- or two-stage procedures. Six of the seven patients were male, and the average patient age was 48 (range, 30-66) years. The injuries involved two middle, two ring, and three little fingers. Three patients underwent single-stage reconstructions to treat a neglected FDP avulsion injury, a neglected zone 1 FDP laceration, and a subcutaneous FDP rupture caused by infection (one patient each). Four patients underwent second-stage reconstruction to treat flexion contractures developing after flexor tenolysis or tendon grafting (one patient each) and flexor tendon rupture after zone 2 primary repair (two patients). The tendons were proximally sutured into appropriate FDP tendons via end-weave anastomoses; the distal end of the graft was anchored using small bone anchor, interlacing suture to the distal stump of the FDP, and pull-through technique. For the first 3 postoperative weeks, the digits were mobilized with a combination of active extension and passive and active flexion in a protective splint. The follow-up period averaged 18 (range, 7-45) months.

Results and Conclusions: The passive range of motion of the proximal and distal interphalangeal (PIP and DIP) joints prior to flexor tendon grafting averaged 144 (range, 115-172)°. The mean active range of motion of these joints at final evaluation was 123 (range, 65-170)°. Using Strickland's formula to assess staged flexor tendon reconstruction, the mean recovery of active motion was 83 % (range, 50-100%). Using the Tang criteria, reconstruction of one digit was graded excellent; reconstructions of three were graded good, two fair, and one poor at final evaluation. We encountered no tendon rupture and no finger required tenolysis.

Summary Points: The results indicate that extrasynovial tendons can survive and heal during EAM, with few adhesions of functional significance. We believe that our distal juncturing technique allows stresses encountered during EAM to be withstood.