Effects of Synovial Interposition on Healing in a Canine Tendon Explant Culture Model

Purpose To investigate whether synovium interposition between repaired tendon ends can integrate into the tendon repair and improve tendon healing strength in a canine tendon explant culture model. Methods We used 80 flexor digitorum profundus tendons from 10 mixed-breed dogs for this study. The flexor digitorum profundus tendons were assigned to 2 groups: repaired tendons with synovium implanted between the cut tendon ends and repaired tendons without any implantation between the tendon ends. The repaired tendons were cultured for either 2 or 4 weeks and then assessed mechanically for rupture strength and histology. Results The strength of the repaired tendons with the synovium interposition was significantly higher (p < .001) than the repaired tendons without interposition at both 2 and 4 weeks. The strength of the repaired tendons at 4 weeks was significantly higher than that at 2 weeks in both groups. Conclusions Interpositional synovial grafts have the potential to accelerate tendon healing when they are implanted at the repair site. The exact mechanism of this effect remains to be elucidated. (J Hand Surg 2010;35A:1153-1159. Copyright (C) 2010 by the American Society for Surgery of the Hand. All rights reserved.)