Practical considerations in anterior cruciate ligament replacement surgery.

The endoscopic method of anterior cruciate ligament (ACL) reconstruction using a patellar tendon graft that is secured with interference screws is a commonly performed procedure. It has many potential pitfalls, the majority of which are secondary to technical errors. Prevention of errors starts with a full knowledge of normal ACL anatomy and any discrepancies with the size and shape of the graft substitute. Accurate tibial and femoral tunnel placement is essential and involves using consistent intra-articular landmarks and achieving specific radiographic criteria. Accurate tunnel placement minimizes graft excursion and impingement against the roof of the intercondylar notch. This will result in maximum knee stability and motion. Much has been written about the principles of graft-tunnel mismatch and interference screw-bone plug divergence. The clinical implications of these potential sources of error remain somewhat controversial and are discussed in this article.