ACCURACY OF NAVIGATED V/S JIG BASED TIBIAL AND FEMORAL TUNNEL PLACEMENT WITH REFERENCE TO ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION.

Abstract

Background: As many as 175,000 anterior cruciate ligament (ACL) reconstructions are performed annually in the United States at a cost > 1 billion dollars. Estimates of the rate of revision surgery are as high as 10%–20%, potentially resulting in as many as 35,000 revisions a year. In addition, errors that are not obvious at short-term or mid-term follow-up may have significant long--term effects in young patients. Studies have demonstrated that the majority of visions are related to technical errors, primarily tunnel placement. Computer-aided navigation systems provide enhanced precision in tunnel placement and may reduce the rate of revision surgery. Computer-aided systems can provide valuable data on rotational and translational laxity of the knee.

Aim: To assess the accuracy of tibial and femoral tunnel placement comparing the Acuflex and Arthrex guides with navigated technique.

Methods: Five formalin preserved cadavers were divided into two groups. An experienced Surgeon comfortable with the jigs and the navigation technique performed all the reconstructions. Group A knees had ACL reconstructions using the Arthrex guide (4 knees) and Group B using the computer navigated technique (5 knees). Quadrupled Hamstring tendon grafts were used for reconstruction. All 9 knees were examined following ligament reconstruction with plain radiography and CT scans to assess the accuracy of the tunnel placement. Computer navigation was performed using the Brain Lab software. Implants used for fixation were Ezlock (Arthrotek, UK) for the femur and interference screw for the tibia.

Results: The findings suggest variability of accuracy in tunnels placement using the two techniques. ACL reconstruction should be carried out with accurate tunnel placement. Care should be taken in placing the tunnel as errors will lead to failure of the reconstructed ligament. Computer aided navigation is recommended in performing ACL reconstructions.