Autologous chondrocyte implantation: current surgery and rehabilitation.

Autologous chondrocyte implantation (ACI) is a treatment option for full-thickness chondral, or osteochondral injuries that are painful, debilitating, and progressive. Goals of surgery and rehabilitation include replacement of damaged cartilage with hyaline or hyaline-like structure, maintained durability to withstand knee intraarticular forces over time with a productive level of function, and restoration of the normal surface congruity of the joint. Intermediate and long-term results are promising in terms of clinical improvement and durability using ACI. This article outlines the surgical technique, the histological and biomechanical principles on which the surgery and rehabilitation process are based, and a recommended rehabilitation protocol.