Ligament-tendon fixation: analysis of a new stitch and comparison with standard techniques.

A newly devised locking loop tendon-ligament suture was evaluated for its clinical application. The suture is relatively simple to use and is particularly suited to flat structures such as the medial collateral ligament, joint capsule, and patellar tendon. It affects tension and resistance to pull out without exerting major purse stringing or bunching. In a laboratory setting, this suture technique has been compared to fixation by individual sutures and several varieties of staple fixation. Simple suture fixation was quite weak, measuring 100 newtons (N). Staple fixation is not only weaker than the ligament suture, but is more highly dependent on bone quality and is generally more variable. When employed with strong suture material, a doubled ligament suture was found to be nearly twice as strong (392 N) as staple fixation into bone (208 N) and demonstrated a mean pullout strength close to the forces observed on human anterior cruciate ligaments. In combination with a well placed ligament staple into good quality bone, fixation was further enhanced (482 N) and statistically significantly improved (P greater than .05).