Anterior cruciate ligament graft fixation--a myth busted?

Anterior cruciate ligament graft fixation has become one of the most investigated topics in the sports traumatology literature. With over 400 publications within the past decade, a plausible explanation for the popularity of the topic would be that anterior cruciate ligament graft fixation represents an obvious clinical problem. Yet this does not seem to be the case. We set out to analyze the veracity of the notion that the fixation site is the weak link in a reconstructed knee in the early postoperative period. A mere temporal association is found between the first clinical reports on increased anterior tibial translation relative to the femur with soft-tissue grafts and the first pullout studies reporting lower ultimate failure loads with such grafts. This association was sufficient to convince the orthopaedic community at large that actual causality exists between soft-tissue graft fixation failure and increased knee laxity during healing. Thus the concept of "graft slippage" was born. Even with the imminent risk of being misconstrued as contentious, we submit that the entire concept of graft slippage is a myth, founded on poor scientific practice and affected by commercial bias. As a way forward, clinically important phenomena should be demonstrated through experiments with clear and sound clinical endpoints. As for preclinical studies, although they are indisputably helpful in the elaboration of such phenomena, serious hazards lie in declaring them a sufficient scientific basis for new research or, worse, for clinical standards of care. More importantly, no matter how sophisticated or fascinating their methodology, preclinical studies do not relieve us from the necessity and duty of proving our theories, whenever possible, with randomized controlled trials.