Osteochondral Autograft Transfer for Focal Osteochondral Defects of the Knee: Indications, Technique, Outcomes, and Future Directions.

➢ Osteochondral autograft transfer (OAT) restores hyaline cartilage and subchondral bone in a single stage, offering a durable joint-preserving option for focal full-thickness articular cartilage defects in young, active patients. ➢ Optimal candidates have unipolar femoral condyle, patellofemoral, or tibial plateau lesions measuring 1 to 4 cm 2 ; outcomes become less predictable once the defect size exceeds 3 cm 2 . Outcomes are further influenced by age, activity level, sex, alignment, instability, and meniscal deficiency, with older, lower-demand patients and those with larger lesions demonstrating comparatively inferior results. ➢ Technical success requires meticulous recipient-site preparation, perpendicular graft harvest, and flush implantation; both arthroscopic and open approaches achieve reliable results. ➢ OAT demonstrates high return-to-sport rates (often >85% within 6 months), significant functional improvements, and superiority over microfracture. Outcomes may be comparable or superior to cellular resurfacing or allograft techniques in appropriately selected patients. ➢ Emerging biologic adjuncts, recess-filling strategies, and donor-site substitutes may enhance graft integration and reduce morbidity, although long-term clinical benefits remain unproven.