Autologous Costal Osteochondral Transplantation for Cystic Osteochondral Lesions of the Talus: Feasible and Effective

Objective: Osteochondral lesions of the talus (OLT) is a common and clinically challenging disease. The optimal management is still under debate. The purpose of this prospective study was to investigate the feasibility and clinical outcomes of autologous costal osteochondral transplantation (ACOT) for the treatment of cystic OLT. Methods: From November 2021 to April 2023, five patients underwent autologous costal osteochondral transplantation (ACOT) for cystic OLT. The demographic data was described, including age, gender, lesion size and location. We prospectively evaluated their functional and imaging outcomes of the five patients for 12 months postoperatively, including numeric rating score (NRS) for pain when walking, Tegner score, American Orthopedic Foot & Ankle Society (AOFAS) score and Foot and Ankle Ability Measure (FAAM) score, and imaging results. A paired t-test was used for preoperative and postoperative comparison of the paired-design dataset. Results: The average age was 36.6 +/- 11.1 years. The average diameter of chondral lesions was 14.95 +/- 2.71 mm, the average diameter of subchondral cysts was 10.66 +/- 1.84 mm, and their average depth was 10.40 +/- 1.86 mm. At 12 months postoperatively, the clinical function indexes improved significantly, including NRS (from 5.2 +/- 2.3 to 0), Tegner score (from 3.2 +/- 0.4 to 5.8 +/- 0.4), AOFAS score (from 72.8 +/- 10.0 to 98.2 +/- 4.0), and FAAM score (FAAM/ADL from 61.2 +/- 24.7 to 99.3 +/- 1.6; FAAM/Sports from 32.5 +/- 13.73 to 96.3 +/- 8.4). Their magnetic resonance observation of cartilage repair tissue (MOCART) scores reached 78.0 +/- 7.6 points. ICRS scores of three patients were nearly normal (10 or 11 points). The biopsy of the surviving grafts showed plenty of hyaline cartilage matrix and scattered chondrocytes histologically. No major severe complications were reported during the 12 months follow-up. Conclusion: ACOT could significantly relieve the symptoms of patients with OLT and improve their clinical function at short-term follow-up. ACOT might be a feasible and useful method for repairing OLT with subchondral cysts.