A prospective evaluation of the anterior horn of the lateral meniscus as a landmark for tibial tunnel placement in anterior cruciate ligament (ACL) reconstruction.

BACKGROUND

The goal of this study was to prospectively evaluate the accuracy and consistency of the anterior horn of the lateral meniscus as a landmark in achieving the desired tibial tunnel location during primary anterior cruciate ligament (ACL) reconstruction.

METHODS

One hundred consecutive adult patients undergoing primary ACL reconstruction were enrolled in the study. One sports-fellowship trained surgeon performed all ACL reconstructions using independent tunnel drilling with an accessory anteromedial portal for the femoral tunnel. All guide pins for the tibial tunnel were placed using a 55-degree guide using the posterior border of the anterior horn of the lateral meniscus as a landmark. Following pin placement, a true lateral fluoroscopic image was obtained. These were digitally analyzed to measure the location of the pin along the length of the tibial plateau.

RESULTS

The average anteroposterior (A-P) distance achieved using the posterior border of the anterior horn of the lateral meniscus as a landmark for tibial tunnel placement was 37.0%±5.2% (mean±standard deviation) [range 26.4%-49.2%]. 66% of tibial tunnels were located between 30.0% and 39.9% of the A-P tibial distance. Only 18% of tibial tunnels localized between 40.0% and 44.9%, the area of the anatomic footprint described by Staubli and Rauschning [9] 16% of patients were significant outliers, with tunnels localizing to 25.0%-29.9% (6 patients) or 45.0%-49.9% (10 patients).

CONCLUSIONS

Use of the posterior border of the anterior horn of the lateral meniscus as a landmark for tibial tunnel placement during anatomic ACL reconstruction yields an inconsistent tunnel location.

LEVEL OF EVIDENCE: II, Prospective study.