Femoral fixation of patellar tendon grafts using the bone-block locking technique in ACL reconstruction. A biomechanical study.

Anterior cruciate ligament (ACL) reconstruction relies on the security of graft fixation. K-wire fixation, heavy non-absorbable sutures tied to a screw staple post or endo-button are currently used for graft fixation. Kurosaka screw fixation may cause rupture of the graft due to excessive stress at the screw-graft interface in the femoral tunnel. To avoid inherent complications, a new bone-tendon-bone graft fixation technique for ACL reconstruction is described and biomechanically compared with the classical interference screw fixation in sheep knee models. A total of 13 pairs of fresh sheep knee specimens, obtained from a local slaughterhouse, were used in this study. Sheep knee specimens (n = 13) were divided into two groups. The right knees were Group I and the left knees were Group II. The right knees in Group I received interference screw systems and the left knees in Group II received the Bone Block Locking system (BBL). The average maximum load was found to be 275.01 +/- 10.75 N for the interference screw system and 389.92 +/- 7.54 N for the BBL system (p = 0.02). Our results indicate that the BBL technique allows a more secure fixation than interference screw fixation. The complications and technical pitfalls of interference screw fixation are not seen in BBL technique. We believe that the BBL technique is more advantageous in comparison to other fixation systems.