Biomechanics and anterior cruciate ligament reconstruction

For years, bioengineers and orthopaedic surgeons have applied the principles of mechanics to gain valuable information about the complex function of the anterior cruciate ligament (ACL). The results of these investigations have provided scientific data for surgeons to improve methods of ACL reconstruction and postoperative rehabilitation. This review paper will present specific examples of how the field of biomechanics has impacted the evolution of ACL research. The anatomy and biomechanics of the ACL as well as the discovery of new tools in ACL-related biomechanical study are first introduced. Some important factors affecting the surgical outcome of ACL reconstruction, including graft selection, tunnel placement, initial graft tension, graft fixation, graft tunnel motion and healing, are then discussed. The scientific basis for the new surgical procedure, i.e., anatomic double bundle ACL reconstruction, designed to regain rotatory stability of the knee, is presented. To conclude, the future role of biomechanics in gaining valuable in-vivo data that can further advance the understanding of the ACL and ACL graft function in order to improve the patient outcome following ACL reconstruction is suggested

The effect of graft choice on functional outcome in anterior cruciate ligament reconstruction

A prospective, randomised, 5-year follow-up study was designed to compare the functional results between patellar tendon and hamstring tendon autografts after anterior cruciate ligament reconstruction. Primary reconstruction was performed in 32 patients using the central third of the patellar ligament and in 32 patients using double-looped semitendinosus and gracilis tendons. All reconstructions were performed by a single surgeon, with identical surgical technique and rehabilitation protocol. Of the total 64 patients in the study, 54 (85%) were available for the 5-year follow-up. No statistically significant differences were seen with respect to Lysholm score, International Knee Documentation Committee (IKDC) classification, clinical and KT-2000 arthrometer laxity testing, single-legged hop test and anterior knee pain. Graft rupture occurred in two patients (8%) in the patellar tendon group and in two patients (7%) in the hamstring tendon group; 23 patients (88%) in the patellar tendon group and 23 patients (82%) in the hamstring tendon group returned to their pre-injury activity level. Good subjective outcome and stability can be obtained by using either graft; no statistically significant differences were found in functional outcome between the grafts