Fixation strength of tibial inlay graft with one versus two screws: a cadaveric study

Various modes of fixation have been advocated for posterior cruciate ligament reconstruction. This study compared pullout forces and modes of failure for 2 commonly used techniques. Ten Achilles tendon-bone plug grafts were fixed to tibial troughs using either one 6.5-mm or two 4-mm cancellous screws positioned anatomically and tested to failure. The constructs did not differ statistically in mean pullout forces (385.2 and 358.8 N for the 6.5-mm and 4-mm screw constructs, respectively). The 2-screw construct failed by pullout, whereas the single-screw fixation failed through fracture. This study provides insight into the fixation used for posterior cruciate ligament reconstruction.