Biomechanical comparison between BioScrew and titanium alloy interference screws for bone-patellar tendon-bone graft fixation in anterior cruciate ligament reconstruction

This investigation compared the maximum load at failure of BioScrew (Linvatec Corp, Largo, FL) and titanium alloy interference screw femoral fixation using a human cadaveric model that approximated the anatomical orientation and physiological strain rate of in vivo bone-patellar tendon- bone (BPTB) graft loading following anterior cruciate ligament reconstruction. Eighteen fresh-frozen human BPTB allografts (10-mm wide, 10- mm thick, 25-mm long bone plugs) with either BioScrew or titanium alloy (Ti 6Al4V) screw (7 x 25 mm) fixation were compared for maximum load at failure at a strain rate of 20 mm/minute. Nine cadaver femurs with bone mineral densities of 0.88 ± 0.18 g/cm² (anterior/posterior) and 1.3 ± 0.24 g/cm² (lateral) received the allografts. No statistical differences were observed in maximum load at failure (P = .95) or failure mode (P = .11) between specimens fixed with either screw type. When biomechanically tested with anatomic orientation and at functionally relevant strain rates, the BioScrew provided maximum load at failure equal to a titanium alloy screw.