The graft/tunnel angles in posterior cruciate ligament reconstruction: a cadaveric comparison of two techniques for femoral tunnel placement.

Purpose: In posterior cruciate ligament reconstruction, the tibial tunnel/graft angle (or killer turn) has been implicated in graft failure when using transtibial tunnel placement. The graft/femoral tunnel angle (or critical corner) can also contribute to shear stress and early graft failure. The purpose of this study was to quantitate the killer turn angle in flexion and extension and to compare critical corner angles using outside-in and inside-out techniques for femoral tunnel placement.