Clinical and Radiological Outcomes of Autologous Osteochondral Transplantation with and without Micronized Allograft Cartilage Matrix Augmentation for Osteochondral Lesions of the Talus

CATEGORY: Ankle; Basic Sciences/Biologics; Trauma INTRODUCTION/PURPOSE: Autologous osteochondral transplantation (AOT) using a cylindrical graft, in the treatment of osteochondral lesions of the talus (OLT) is typically indicated for patients with larger lesions. However, with lesions that are irregular in shape, the AOT graft may not completely replace the lesion. For these lesions, we utilize Extracellular Matrix Cartilage Allograft (EMCA) augmentation in AOT to act as a physiologic grout between the host and graft interface. The purpose of this study was to evaluate the clinical and radiological outcomes of AOT with concentrated bone marrow aspirate (CBMA) and EMCA augmentation in the treatment of OLT. METHODS: A retrospective analysis comparing patients treated with AOT/CBMA alone and AOT with CBMA/EMCA was performed. Clinical outcomes were evaluated with the use of the Foot and Ankle Outcome Score (FAOS). Magnetic resonance imaging (MRI) was evaluated with the use of the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score. Cyst formation was also evaluated on postoperative MRI. RESULTS: Twenty-six patients were included in the AOT + CBMA/EMCA group, with 10 males and 16 females. Thirty-four patients were included in the AOT/CBMA group, with 17 males and 17 females. The mean symptoms, pain, ADL, sports activities, and QOL scores in FAOS significantly improved in both groups (p<0.001), but there was no significant difference between groups at final follow-up. There was no significant difference between the mean MOCART scores between groups (p=0.118). In the AOT/CBMA group, 2 patients (7.7%) complained of knee pain and 5 patients (19.2%) required additional surgery (2 hardware removals and 3 arthroscopic debridements of scar tissue in the ankle). In the AOT + CBMA/EMCA group, 3 patients (8.8%) complained of knee pain, and one patient (2.9%) required hardware removal. CONCLUSION: The current study demonstrated that AOT combined with CBMA and EMCA was an effective surgical treatment for OLT, providing good clinical and radiological outcomes. However, the benefit of combining ECMA with CBMA in small chondral defects at the host graft interface may be marginal as the biologic effect is induced by the CBMA and the mechanical scaffold effect of ECMA may not be required in such small defects.