Osteochondral Allograft Transplantation of the Knee: Analysis of Failures at 5 Years

Background: Osteochondral allograft transplantation (OAT) is being performed with increasing frequency, and the need for reoperations is not uncommon. Purpose: To quantify survival for OAT and report findings at reoperations. Study Design: Case series; Level of evidence, 4. Methods: A review of prospectively collected data of 224 consecutive patients who underwent OAT by a single surgeon with a minimum follow-up of 2 years was conducted. The reoperation rate, timing of reoperation, procedure performed, and findings at surgery were reviewed. Failure was defined by revision OAT, conversion to knee arthroplasty, or gross appearance of graft failure at second-look arthroscopic surgery. Results: A total of 180 patients (mean [SD] age, 32.7 +/- 10.4 years; 52% male) who underwent OAT with a mean follow-up of 5.0 +/- 2.7 years met the inclusion criteria (80% follow-up). Of these, 172 patients (96%) underwent a mean of 2.5 +/- 1.7 prior surgical procedures on the ipsilateral knee before OAT. Forty-eight percent of OAT procedures were isolated, while 52% were performed with concomitant procedures including meniscus allograft transplantation (MAT) in 65 (36%). Sixty-six patients (37%) underwent a reoperation at a mean of 2.5 +/- 2.5 years, with 32% (21/66) undergoing additional reoperations (range, 1-3). Arthroscopic debridement was performed in 91% of patients with initial reoperations, with 83% showing evidence of an intact graft; of these, 9 ultimately progressed to failure at a mean of 4.1 +/- 1.9 years. A total of 24 patients (13%) were considered failures at a mean of 3.6 +/- 2.6 years after the index OAT procedure because of revision OAT (n = 7), conversion to arthroplasty (n= 12), or appearance of a poorly incorporated allograft at arthroscopic surgery (n = 5). The number of previous surgical procedures was independently predictive of reoperations and failure; body mass index was independently predictive of failure. Excluding the failed patients, statistically and clinically significant improvements were found in the Lysholm score, International Knee Documentation Committee score, Knee injury and Osteoarthritis Outcome Score, and Short Form-12 physical component summary at final follow-up (P < .001 for all), with inferior outcomes (albeit overall improved) in patients who underwent a reoperation. Conclusion: In this series, there was a 37% reoperation rate and an 87% allograft survival rate at a mean of 5 years after OAT. The number of previous ipsilateral knee surgical procedures was predictive of reoperations and failure. Of the patients who underwent arthroscopic debridement with an intact graft at the time of arthroscopic surgery, 82% experienced significantly improved outcomes, while 18% ultimately progressed to failure. This information can be used to counsel patients on the implications of a reoperation after OAT.