Repair of soft tissue to bone using a biodegradable suture anchor.

The medial collateral ligaments of 18 New Zealand rabbits were surgically detached from bone. In one knee, the ligament was repaired using a biodegradable suture anchor composed of a co-polymer of lactic and glycolic acid. The contralateral medial collateral ligament was not repaired. Animals were sacrificed at 4, 8, and 12 weeks after the operation, and the knee that had the ligament repair was compared with the contralateral control knee. All knees were tested manually tested for stability to valgus stress and then prepared for histologic examination. Medial collateral ligaments repaired using the biodegradable suture anchor demonstrated stability to valgus stress and anatomic healing at the bone-tendon junction. Resorption of the implant was virtually complete by 12 weeks. All specimens demonstrated less inflammatory reaction to the suture anchor than to the attached Vicryl suture. This contrasts with the control group, which was grossly unstable and demonstrated scarring in this nonanatomic position. These results demonstrate efficacy of this particular material of biodegradable implant and justify further investigative efforts.