Autologous Chondrocyte Transplantation For Articular Cartilage Injuries

In the two previous posts, we discussed the microfracture technique and the mosaicplasty technique for articular injuries. The third major procedure for articular cartilage injuries is autologous chondrocyte transplanatation (ACT) or autologous chondrocyte implantation (ACI). This is also the most invasive of the three. This method is usually chosen if the defect is larger than 5 cm and especially if there's a "kissing lesion" (or touching lesions on two joint surfaces).

Kissing lesions- both surfaces affected

The patient undergoes two surgeries for this. In the first, a small patch of healthy articular cartilage the size of one of two Tic Tacs is harvested (from the knee) and sent to a laboratory. It is subsequently grown in a protected medium to get more healthy articular cartilage. During the second surgery two to three weeks later, these newly grown articular cartilage cells are placed onto the defect (which is cleaned) to restore the surface.

There are of course variations to the three surgical interventions described in these few posts like a cell based, biodegradeable membarnes or scaffolding, stem cells etc.

Return to light sporting activities is usually allowed after six months with full return to sports at around nine to twelve months after the second surgery depending on how the patient recovers.

These have strong implications for physiotherapists in the management of these disorders as physiotherapists take charge of the patient's rehabilitation program after surgery. Successful rehabilitation for a patient requires the physiotherapist to have knowledge of the biology of articular cartilage and the factors that will influence damage and repair.

This requires restoring motion and muscle function while reducing functional limitations during weight bearing activities. Patient education and setting of realistic goals based on the extent of the damage is crucial to a successful outcome.

The postoperative management of patient varies according to the surgery performed. There are different time frames for non and partial weight bearing, specific physiotherapy treatment and use of continuous passive motion (CPM) machines. Other than improving range, CPM machines provide a mechanical stimulus to joints to promote healing (Sledge, 2001).

A good surgical technique is only as good as its rehabilitation. Come and see us if you have articular cartilage injuries as we definitely know what to do.


References

Brittberg M, Lindahl A et al (1994). N Eng J Med. 331(14): 889-95. DOI: 10.1056/NEJM199410063311401.

Vasiliadis HS and Wasiak J (2016). Autologous Chondrocyte Implantation For Full Thickness Articular Cartilage Defects Of The Knee. Cochrane Database of Systematic Reviews. Issue 10. Art. No CD003323. DOI: 10.1002/14651858.CD003323.pub3.

Sledge, SL (2001). Microfracture Techniques In The Treatment Of Osteochondral Injuries. Clinics Sp Med. 20(2): 365-377.