Femoral Malpositioning of Anterolateral Ligament Reconstruction Is a Significant Risk Factor for Anterior Cruciate Ligament Graft Failure

Abstract

Background:

The femoral attachment of the anterolateral ligament (ALL) reported by anatomic studies is posterior and proximal to the lateral femoral epicondyle.

Purpose:

To assess the femoral positioning of the ALL graft while performing a percutaneous technique and evaluate the correlation between this positioning and the graft rupture rate, as well as clinical and functional outcomes.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A total of 211 patients undergoing combined anterior cruciate ligament (ACL) and ALL reconstruction were included. Radiological measurements, Knee injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee (IKDC) score, and graft failure rate were collected at 24 months after surgery.

Results:

The rate of anatomic positioning of ALL femoral anchors was 79.1% (n = 167). The mean proximal and posterior distances relative to the ALL anatomic femoral position were 1.4 ± 2.8 mm and 0.2 ± 0.2 mm, respectively. The rate of outliers, defined as >5 mm from the anatomic position, was 20.85% (n = 44). The mean KOOS and IKDC score were 84 ± 10.9 and 80.1 ± 11.3, respectively. No statistically significant difference in KOOS and IKDC score was observed between the group of patients with anatomic positioning and the group of outliers (P = .1). The rate of ACL rerupture for all patients was 3.79% (n = 8). Of these, 87.5% (n = 7) were outliers. The correlation between ALL femoral malpositioning and ACL rerupture was statistically significant (P < .00001).

Conclusion:

Independent ALL reconstruction while performing a percutaneous technique enabled anatomic positioning of the ALL graft in 79% of cases. The femoral malpositioning was correlated with a higher ACL graft rerupture rate but not with a decrease in the functional outcomes.