OBJECTIVETo introduce the process and outline of fluoroscopy-based navigation system assisted anterior cruciate ligament (ACL) reconstruction, and evaluate its feasibility and accuracy.

METHODSFrom September 2005 to February 2006, there were 30 cases ACL rupture patients who received fluoroscopy-based navigation system assisted arthroscopy operations for ACL reconstruction (navigation group). At the same time, there were 40 patients who underwent traditional ACL operation (traditional group). For the navigation group, the proper placement of femoral and tibial tunnels was planned preoperatively in standard AP and lateral X-ray view. Intraoperative fluoroscopic images were taken and input into navigation computer system to form the virtual interactive working fields. After placement and registration, signals from patient trackers, which fixed on the distal femur and tibia respectively, and tool trackers, which attached with ACL tibial and femoral guide, were captured by the optic navigation camera and the navigation computer system could pursue the real-time position of the ACL tools and projected into working field to help precise placement of femoral and tibial tunnels. Then results of two groups were observed and evaluated.

RESULTSFor navigation group, the mean time extension was 20 min. The tibial tunnel position was measured in all these cases. The tibial tunnel position of navigation group was 45.90% (SD 2.36%), and the traditional group was 41.05% (SD 6.01%). The difference was statistically significant (P < 0.05).

CONCLUSIONFluoroscopy-based navigation system assisted ACL reconstruction improves the accuracy and reproducibility of the tunnel placement.