Advances and existing challenges facing implants in the treatment of osteochondral defects: a narrative review of the current literature.

INTRODUCTION

Focal osteochondral defects of the knee represent a significant clinical challenge due to pain, functional impairment, and the risk of early osteoarthritis. Conventional cartilage repair techniques may provide satisfactory results in selected patients but are often limited by donor-site morbidity, multistage procedures, and inconsistent long-term outcomes. Recent advances in biomaterials and tissue engineering have led to the development of osteochondral implants designed to restore the entire osteochondral unit and improve functional recovery.

AREAS COVERED: This narrative review summarizes the current literature on the most widely investigated osteochondral implants for the treatment of focal knee defects, including AMIC with Chondro-Gide, MaioRegen, Agili-C, and focal metal resurfacing implants. The available clinical evidence was analyzed with particular attention to implant design, surgical indications, clinical outcomes, and complications. In addition, recent technological developments and the main challenges affecting implant integration and durability were examined.

EXPERT OPINION: From an expert perspective, current implants show encouraging short- and mid-term clinical outcomes, but none has yet emerged as the standard of care. Future research should focus on long-term comparative studies, improved patient-selection strategies, and technological innovations aimed at optimizing osteointegration, durability, and defect-specific treatment.