When a patient tears or ruptures the ACL ligament inside the knee, surgery is often needed to restore the stability that the anterior cruciate ligament (ACL) provides the knee. The best way to do this is to take tissue (usually a tendon) from some place else around the patient’s own knee (that’s an autograft) or from a donor bank (allograft) and stitch it in place.
More than a quarter of a million ACL reconstruction surgeries are performed in the United States each year. About 80 per cent of those use autografts. Autografts have the advantage of a very low (rare) rejection rate. Since it’s your own tissue, your body is less likely to attack the tissue, so the graft takes successfully. On the flip side, there is the disadvantage with autografts of causing problems at the donor site such as infection, persistent pain, and possible deformity.
Allografts eliminate those problems but have their own issues with potential tissue rejection by the patient. According to a recent study comparing results from of autografts to allografts, allografts tend to produce a knee that isn’t as stable as joints treated with autografts. In other words, there’s greater joint laxity (looseness) with allografts when using joint stability tests described.
Failure can be defined differently by different surgeons and by individual patients. The graft may not die and slough off (that’s for sure a failure), but the residual joint laxity can interfere with function. Or for the athlete, failure might be described as the inability to get back to a preinjury level of sports participation.
The probability of graft failure is rare but not completely eliminated. Ask your surgeon to review your situation for any risk factors (age, general health, use of tobacco or other chemicals that can slow or delay healing). Assess your own risk for graft failure. It’s likely that you will have a very low risk for graft failure but it would be good to have some reassurance about this concern.