Autograft vs Allograft Comparison in Pediatric Medial Patellofemoral Ligament Reconstruction

Background: Patella instability and medial patellofemoral ligament (MPFL) injury are frequently encountered in pediatric patients. MPFL reconstruction is often chosen to treat this condition with good results; however, no consensus has been reached about which graft or technique to use. The purpose of this study was to evaluate the differences in graft survivorship, clinical outcomes (assessed with Kujala scores), and cost between autograft and allograft usage in MPFL reconstruction in pediatric patients. Methods: In this retrospective review of patients who underwent MPFL reconstruction between 2012-2015, autograft gracilis tendon was used for Group 1, and allograft gracilis tendon was used for Group 2. Outcomes were graft survivorship, postoperative Kujala scores, operative time, costs, graft size, and tibial tubercle-trochlear groove distance. Results: Fifty-six patients were included in this study, 21 in Group 1 and 35 in Group 2. No differences in age, sex, or chronicity were seen between the groups. Patients in Group 1 had longer operative times (134.5 minutes vs 97.3 minutes, P=0.0002), higher rates of graft failure (28.6% vs 0%, P=0.0037), and lower Kujala scores (80.3 vs 92.1, P=0.0032) compared to Group 2. All graft failures occurred in patients with chronic patella dislocations and occurred an average of 13.8 months postoperatively. Overall, autograft was costlier than allograft because of the cost of reoperation. Conclusion: This study supports the use of allograft for chronic patellar instability because of improved graft survivorship and clinical outcome scores, as well as the lower cost and reoperation rate.