Surgical Intervention for Small Osteochondral Lesions (<1 cm): Proceedings of the International Consensus Meeting on Cartilage Repair of the Ankle

Background Evidence guiding best practices in ankle cartilage repair remains limited and of poor quality. To address this, an international expert group convened to establish consensus opinions on key topics, focusing here on the treatment of small osteochondral lesions, defined as less than 1 cm. Methods Experts from 25 countries participated in a structured Delphi-based consensus process. Blinded surveys, structured questionnaires, and in-person discussions were used to develop and refine statements, supported by literature review and graded evidence (A1-E). Consensus strength was defined as consensus (51%-74%), strong consensus (75%-99%), or unanimous (100%). Results Fourteen of 15 proposed statements achieved consensus, including 13 with ≥86% agreement. Bone marrow stimulation (BMS) was recommended for full-thickness osteochondral lesions of the talus (OLTs) that failed conservative therapy, ideally <10 mm in diameter and <100 mm 2 in area, with poorer outcomes expected in larger lesions. Experts emphasized thorough debridement to stable margins, careful subchondral perforation, and the potential value of biologic augmentation such as platelet-rich plasma or concentrated bone marrow aspirate. Repeat BMS was considered a limited option with inferior outcomes compared with primary procedures or salvage techniques. Conclusions This international consensus provides standardized guidance for the indications, technique, and biologic augmentation of BMS in the management of OLT. The recommendations redefine lesion size thresholds and clarify the restricted role of revision BMS, offering a global reference framework for clinical practice and future research.