Midterm Prospective Evaluation of Structural Allograft Transplantation for Osteochondral Lesions of the Talar Shoulder

Abstract

Background: In cases of large osteochondral lesions of the talus (OLTs), fresh structural or bulk osteochondral allograft transplantation has yielded favorable outcomes in several retrospective and few prospective case series. The purpose of this study was to prospectively evaluate patients who received fresh structural allograft transplantation of the talar shoulder. Methods: A prospective evaluation of patients who received a fresh structural allograft of an OLT was performed. Preoperative imaging included magnetic resonance imaging (MRI) and/or computed tomography (CT) with plain radiographs. The following patient-reported outcomes questionnaires were administered preoperatively and yearly after surgery: 36-Item Short-Form Health Survey (SF-36), visual analog scale (VAS) for pain, and the Short Musculoskeletal Functional Assessment (SMFA). Preoperative and postoperative imaging were evaluated for allograft assimilation, evidence of arthritic changes, or functional range of motion abnormalities. Results: Thirty-one patients with a mean age of 41.4 years (±14.1, range 18-69) underwent structural fresh osteochondral allograft transplantation to the talar shoulder and were included in this study. The mean follow-up was 56.2 months (±36.1, range 24-142). The majority of patients were female (n=17, 54.8%), reported some history of prior ankle trauma (n=21, 67.7%), and underwent prior ankle surgery (n=23, 74.2%). The mean lesion size on CT scan was 1879 mm3 (n = 27) compared to the mean lesion size of 3877 mm3 (n = 21) on MRI. There was a significant improvement in the mean preoperative VAS score ( P < .0001), SF-36 score ( P < .0005), SMFA bother index ( P < .0015), and the SMFA function index ( P < .0001) at final follow-up. A total of 15 (48.4%) patients underwent an additional surgery following their osteochondral allograft transplant, most commonly arthroscopic debridement or removal of hardware, performed at an average of 25.2 (±13.0) from their index procedure. There was one failure that required a total ankle replacement. The overall graft survival rate was 96.8%. Conclusion: Fresh, structural allograft transplantation resulted in significant improvement in patient-reported postoperative pain and function in patients suffering from OLTs. The graft survival rate was 96.8% at a mean of 56.2 months follow-up, with half of patients requiring a second procedure. Level of Evidence: Level IV, prospective case series.