Autologous chondrocyte implantation (ACI)
Autologous chondrocyte implantation relies on newly grown cartilage cells. It requires two surgeries.
First, the patient undergoes arthroscopic surgery to remove a small piece of healthy cartilage from a knee joint's non-weight bearing area. That cartilage is cultured, allowing new cartilage cells to grow.
Three to five weeks after the first surgery, a second surgery is performed to implant the newly grown cartilage cells into the affected knee joint.
This second surgery is not done arthroscopically; it requires an open incision.
This procedure may be recommended when the cartilage injury is large (up to several centimetres) or multiple cartilage injuries to repair.