A comparison between tendon-bone contact areas of autografts prepared for single or double tunnel anterior cruciate ligament reconstructions

Abstract

Objectives: We calculated tendon graft-bone contact areas of hamstring autografts prepared for single-bundle (single femoral-tibial tunnel) or double-bundle (double femoral-tibial tunnels) anterior cruciate ligament (ACL) reconstructions. Materials and methods: Semitendinosus tendons were obtained from 24 patients during ACL reconstruction. After determination of the proper graft lengths for a presumable ACL reconstruction, the grafts were divided into two equal bundles and two Ti-Cron sutures were placed at the distal end of each bundle. The proximal and distal radii of the grafts were measured with the help of graft sizing tubes both separately for two individual bundles and then for two bundles placed together. The overall graft-bone tunnel contact areas were calculated assuming that a 10 mm of each bundle would be inserted into the bone tunnel; thereafter, total graft contact areas obtained in the femoral and tibial tunnels were compared between single- and double-bundle applications.
Results: The mean femoral and tibial contact areas in the single-bundle technique were 280.8 mm2 and 305.6 mm2, respectively. The mean contact areas for double-bundle applications were 392.7 mm2 for the femoral and 419.3 mm2 for the tibial tunnels, with increases by 39.9% and 37.2%, respectively. Increases in the contact areas were significantly different for the double-bundle technique (p=0.000).
Conclusion: Increased graft contact areas both in the femoral and tibial tunnels by the use of the double-tunnel technique may provide a better graft-bone attachment, a more rapid healing, and promote the biomechanical strength of ACL reconstructions.