Computer-assisted, anatomic, double-bundle anterior cruciate ligament reconstruction.

Accurate placement of the separate anteromedial bundle and posterolateral bundle bone tunnels required for anatomic, double-bundle anterior cruciate ligament reconstruction remains a concern, and the advantages the technique confers, in terms of laxity control, may be lost with incorrect tunnel positioning. We present an image-free, computer-assisted, double-bundle reconstruction technique using specifically designed software. This assists tunnel positioning and allows the behavior of virtual anteromedial and posterolateral bundle grafts to be modeled. Data on graft length change, obliquity, and possible notch impingement are fed back to the surgeon via the interactive, touch-screen navigation display. Tunnel length and obliquity may also be determined. In addition, the software allows preoperative and postoperative navigated laxity analysis, which includes objective measurement of pivot shift.