AANA/SOMOS Course Materials (August 2021)-2021The Anterolateral Ligament

2021The Anterolateral Ligament_ Basic Training for Why, When, and How

Pdf Summary

This presentation by Dr. Kevin F. Bonner discusses the anterolateral ligament (ALL) and lateral extra-articular procedures in anterior cruciate ligament reconstruction (ACLR), focusing on why, when, and how to implement them. Historically, extra-articular reconstructions were standard before ACLR became prevalent, but isolated extra-articular techniques showed poor long-term outcomes, largely due to biomechanical inadequacies.<br /><br />Renewed interest in lateral procedures, including lateral extra-articular tenodesis (LET) and ALL reconstruction, arises from recognition that ACLR alone may not fully control anterolateral rotatory instability—manifested as coupled anterior translation and internal rotation—especially in young athletes with high failure rates and persistent pivot shift.<br /><br />Anatomically, the anterolateral complex (ALC), including the ALL and Kaplan’s fibers of the iliotibial band (ITB), acts as secondary stabilizers to anterolateral rotation after ACL injury. Biomechanical studies reveal that combined injuries to ACL and ALC cause abnormal kinematics not fully corrected by ACLR alone, supporting lateral augmentation in some cases. However, conflicting data suggest that if the ITB is intact or with certain grafts like bone-patellar tendon-bone (BTB), lateral procedures may not be necessary and might risk overconstraint.<br /><br />High-level clinical evidence, including the STABILITY trial (Level 1), demonstrates that adding LET to hamstring tendon ACLR in high-risk young patients reduces graft rupture rates and persistent rotatory laxity at two years without significant long-term functional compromises. Similar trends are noted in elite athletes, revisions, and patients with high-grade pivot shifts or chronic laxity.<br /><br />Current indications for lateral augmentation include high-grade or persistent pivot shift, revision ACLR without technical errors, chronic ACL deficiency, and "high-risk" patient profiles. Risks include potential overconstraint, infection, hardware morbidity, and cost.<br /><br />Surgical approaches contrast lateral extra-articular tenodesis (non-anatomic, open, below lateral collateral ligament) versus anatomic ALL reconstruction (minimally invasive, superficial to LCL). Biomechanical superiority favors LET, though clinical data are insufficient to definitively prefer one technique.<br /><br />In summary, lateral extra-articular procedures offer valuable rotational stability augmentation in selected patients with ACL injury, particularly in high-risk or revision settings, but patient selection, surgical technique, and risk-benefit assessment remain critical.

Keywords

anterolateral ligament

lateral extra-articular procedures

anterior cruciate ligament reconstruction

anterolateral rotatory instability

lateral extra-articular tenodesis

ALL reconstruction

anterolateral complex

pivot shift

STABILITY trial

high-risk ACL patients