Management of focal cartilage defects in the knee - Is ACI the answer?

Injuries to the articular cartilage of the knee are common. They alter the normal distribution of weightbearing forces and predispose patients to the development of degenerative joint disease. The management of focal chondral lesions continues to be problematic for the treating orthopaedic surgeon. Although many treatment options are currently available, none fulfill the criteria for an ideal repair solution: a hyaline repair tissue that completely fills the defect and integrates well with the surrounding normal cartilage. Autologous chondrocyte implantation (ACI) is a relatively new cell-based treatment method for full-thickness cartilage injuries that in recent years has increased in popularity, with early studies showing promising results. The current article reviews the nature of cartilage lesions in the knee and the treatment modalities utilized in their management, focusing on the role ACI plays in the surgical treatment of these complex injuries.