ACL Reconstruction with Immediate Anatomic Re-attachment of the Native ACL in an Ovine Model Results in Minimal Kinematic Differences and Greater Evidence of Early OA Compared with Sham Controls

O'Brien, E J O; Beveridge, J E; Huebner, K D; Heard, B J; Tapper, J E; 1,2 Shrive, N G; +Frank, C B. +The McCaig Institute for Bone & Joint Health, University of Calgary and Schulich School of Engineering, University of Calgary, Alberta, Canada [email protected] INTRODUCTION Much clinical evidence exists that normal joint stability may not be fully restored after all anterior cruciate ligament (ACL) reconstructions which could explain some of the occurrence of premature osteoarthritis (OA) in these patients. We have developed an ovine model of relatively ‘idealized’ reconstruction in which we core out the femoral insertion of the normal ACL on its boney insertion and immediately reattach the bone core + ligament in its original anatomic location. The aims of the current study were to evaluate the stability of these joints up to 20 weeks following such simulated ACL reconstruction compared with sham surgery, and to perform detailed gross examination of these joints for evidence of OA. We hypothesized that following idealized ACL reconstruction, like sham surgery, joint kinematics would be unchanged and that there would be no evidence of increased OA change compared with age matched controls.