This is a two-step procedure that takes several weeks to complete. First, healthy cartilage cells are arthroscopically removed from a non-weight bearing area of the knee. The cells are then grown in the laboratory for around six to eight weeks.
An open surgical procedure, called an arthrotomy, is then done to implant the newly grown cells. A layer of bone-lining tissue, called periosteum, is sewn over the area and sealed with fibrin glue. The newly grown cells are then injected into the defect under the periosteal cover.
ACI is most often recommended for younger patients who have single defects larger than 2 cm in diameter. ACI uses a patient’s own cells, so there is no danger of a patient rejecting the tissue.