Effect of Platelet-Rich Plasma With Fibrin Matrix on Healing of Intrasynovial Flexor Tendons

Purpose To investigate the effects of platelet-rich plasma (PRP) with fibrin matrix on the healing of intrasynovial flexor tendons in a rabbit model in vivo. Methods We transected and repaired 156 toe flexors of 73 rabbits using the technique of Tsuge et al and a simple running epitendinous suture. We randomly assigned Repaired tendons to groups that recieved no additional treatment (control) or to which we applied PRP, fibrin (F), or PRP with fibrin matrix (PRP-F) at the repair site. We scored edema and adhesion at 2, 3, and 6 weeks after surgery, and linearly tested repaired tendons for load to failure. We also histologically evaluated tendons at 2 and 3 weeks. Results Edema scores and adhesion scores did not significantly differ among the 4 groups at any time point. Mean load to failure in the PRP-F group (14.7 N) was the highest among the 4 groups at 2 weeks after surgery, and was significantly higher than in the control group (10.0 N). Median histological scores in the PRP-F group (3.3 points) were significantly higher than in the control group (1.0 point). Mean load to failure in the PRP-F group (16.1 N) was highest, and median histological scores in the PRP-F group (3.5 points) were higher than in the control group (2.4 points) at 3 weeks, although there were no significant differences at 3 or 6 weeks. Conclusions In a rabbit model of cut flexor tendons, PRP with fibrin matrix significantly increased healing strength within 2 weeks after surgery. Side effects such as increases in toe edema or adhesions around the tendons did not arise.