Surgery to repair damage to the surface of a joint has been around since the early 1950s. But some of the more modern chondrocyte-based therapy (as it’s now called) is a more recent phenomenon. The word chondrocyte refers to cartilage cells.
Studies so far have shown some pretty good results with autologous chondrocyte implantation (ACI). It’s a two-part operation designed to restore rahter than repair damaged cartilage. The surgeon removes some of the healthy cartilage (chondrocytes) from an area of the joint that doesn’t see much action (force or load during weight-bearing activities).
The cells are taken to a lab where they are treated to grow additional cells. When there are enough cells, you go back to the operating room and the surgeon places the new cells into the holes like a plug. A special cover is placed over the plug to protect it while the joint incorporates the new cells.
But how does it compare to other restorative techniques used? And now that surgeons have found a variety of different ways to do the ACI procedure, which one works best? To find out, a group of surgeons from the Sports Medicine Center at Ohio State University compare autologous chondrocyte implantation (ACI) against other surgical treatment techniques for this problem. They conducted a review of all the studies already published on this topic and analyzed the data. Here are a few brief findings:
Autologous chondrocyte implantation has the most durable results. The repair tissue that forms holds up better than other repair techniques. Autologous chondrocyte implantation has better short-to medium-term results than microfracture but equal results with osteochondral autograft transplantation.
Long-term results aren’t available yet to show a clear front-runner of the various restorative techniques.Outcomes have been improving over time as the surgical techniques improve. The method used to cover the graft (periosteal, collagen, scaffolds) and protect it doesn’t seem to matter. Results are comparable among the various choices.
Certain patient characteristics do make a difference. Younger, more active patients have the best results, especially if they have the surgery early when the lesion is small. The best outcomes occur in patients who have not had any previous knee surgeries and who don’t have any other injury or damage to the knee ligaments or other knee cartilage.
So, although the autologous chondrocyte implantation procedure is safe and effective, long-term results for large numbers of patients just aren’t available yet.