Anterior cruciate ligament reconstruction using navigation: a comparative study on 60 patients.
BACKGROUND
Poor outcome in anterior cruciate ligament reconstruction is often related to tunnel position.


OBJECTIVE
Improving accuracy of the tunnel position will lead to improved outcome.


METHODS
Randomized controlled trial; Level of evidence, 1.


METHODS
Sixty patients were randomized to either standard instrumentation or computer-assisted guides to position the tibial and femoral tunnels. The results were evaluated on clinical outcome based on International Knee Documentation Committee form (laxity) and radiologic assessment: radiologic Lachman (Telos at 150 and 200 N) and analysis of the tunnel positions.


RESULTS
International Knee Documentation Committee laxity was level A in 22 knees in the conventional group (mean, 1.5 mm at 200 N) compared with 26 navigated knees (mean laxity, 1.3 mm; P = .49). Laxity was less than 2 mm in 96.7% of the navigated group and 83% of the conventional group (P = .292). The variability of laxity in the navigated group was significantly less than in the conventional group, with the standard deviation of the navigated group being smaller than that in the conventional group (P = .0003 at 150 N and .0005 at 200 N Telos). A significant difference (P = .03) was found between the groups in the ATB value (distance between the projection of the Blumensaat line on the tibial plateau and the anterior edge of the tibial tunnel), characterizing the sagittal position of the tibial tunnel (negative ATB values imply graft impingement in extension). In the conventional group, mean ATB was -0.2 (-5 to +4), whereas it was 0.4 (0 to 3) in the navigated patients. There were no negative ATB values in the navigated group.


CONCLUSIONS
This study confirms that the accuracy and consistency of tibial tunnel position can be improved by the use of computer-assisted navigation and that the clinical result in terms of laxity is more reliable.
Orthopaedic Department, University of Grenoble, CHU Grenoble, BP 217, 38043 Grenoble, France. SPlaweski@chu-grenoble.fr
Stephan
S
Plaweski
Julian
J
Cazal
Philip
P
Rosell
Philippe
P
Merloz
D000293:Adolescent; D000328:Adult; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D000070598:Anterior Cruciate Ligament Injuries; D001696:Biomechanical Phenomena; D016009:Chi-Square Distribution; D005260:Female; D005269:Femur / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D019651:Plastic Surgery Procedures / Q000295:instrumentation*; D025321:Surgery, Computer-Assisted / Q000295:instrumentation*; D013977:Tibia / Q000601:surgery; D016896:Treatment Outcome