No difference in clinical results between femoral transfixation and bio-interference screw fixation in hamstring tendon ACL reconstruction. A preliminary study

Abstract

Hamstring tendon autograft has become a popular graft choice for anterior cruciate ligament (ACL) reconstruction, but there is no consensus on the ideal technique of fixation. We performed a pilot randomized controlled study to compare the clinical and mechanical outcome of two femoral fixation techniques for anterior cruciate ligament (ACL) reconstruction using hamstrings graft. We recruited 30 patients with a chronic unilateral tear of the anterior cruciate ligament. In all patients, quadrupled hamstring graft was used for ACL reconstruction. In 15 patients, femoral graft fixation was performed using Bio-interference Screws fixation (Arthrex, Inc. Naples USA) (Group 1). In the other 15 patients, femoral graft fixation was performed using BioTransFix femur extra cortical transverse fixation (Arthrex, Inc. Naples USA) (Group 2). In both groups, tibial fixation was achieved with a Delta bio-absorbable interference screw (Arthrex). Both groups were comparable with regard to demographic data, pre-operative activity level, mechanism of injury, interval between the injury and the operation, and pre-operative knee laxity measurements. An independent observer, who was blinded with regard to the involved leg and the type of graft, performed the outcome assessment with the use of a Rolimeter arthrometer (Aircast), and the International Knee Documentation Committee. At 13 months follow up, all patients except one had functionally normal or nearly normal IKDC objective scores. The mean IKDC subjective score was 83.38+/-9.4 in Group 1 and 79.92+/-11.01 in Group 2 (P>.05). The side to side laxity as measured with the Rolimeter arthrometer was 1.5 mm+/-1 (range 0-3) for Group 1, and 2 mm+/-1 (range 0-3) for Group 2 (P>.05). Femoral Biotransfix fixation and Bio-interference Screws fixation provide comparable mechanical stability and clinical outcome at 13 months follow up. BiotransFix fixation is an effective alternative to other devices. Our preliminary study shows that there is no evidence to prefer femoral transfixation to the more traditional, technically less demanding, and more economical interference screw fixation. A full study requires 368 participants.