Revision surgery for failed anterior cruciate ligament reconstruction in the knee

Anterior cruciate ligament (ACL) reconstruction is a commonly performed surgical procedure in the knee. Revision following failed ACL reconstruction surgery is an increasingly common procedure. Revision surgery can be complicated due to the large variability of methods of primary ACL reconstruction, and the presence of bony defects and hardware. The cause of failure of the original ACL graft must be identified. The surgeon must have a strategy to deal with various problems and be flexible when operating on these patients. Outcomes following revision ACL surgery should not be expected to be as good as following primary ACL surgery, and patients should be counselled regarding this. Even if a stable knee is achieved objectively, subjective patient related outcomes are not as good as following primary ACL reconstruction. There is also a higher rate of re-rupture after revision ACL surgery, and thus return to sport is less likely. Damage to the chondral surfaces has a significant effect on the outcome following revision ACL surgery. An unstable ACL-deficient knee has a higher incidence of chondral damage and there may be a role for revision ACL surgery for its protective effect against further chondral damage, even if subjective outcomes are not as good.