Lateral Extra-Articular Tenodesis (LET)

The LET procedure involves tightening the lateral structures of the knee — specifically the iliotibial band — to prevent excess rotation and shift. Think of it as a “seatbelt” added to the outside of the knee that works alongside your ACL reconstruction to provide an additional layer of rotational control. While LET is no longer used as a standalone treatment for ACL insufficiency, its role as an adjunct to arthroscopic ACL reconstruction has received much greater attention in recent years.

Standard ACL reconstruction restores forward stability of the knee very reliably. However, some patients continue to experience a “giving way” sensation caused by rotational instability even after reconstruction. Patients at highest risk are generally those aged 14 to 25 years with two or more of the following factors: returning to a contact or pivoting sport, a high-grade pivot-shift test (grade 2 or higher) on examination, and generalized ligamentous laxity or knee hyperextension greater than 10 degrees.

Additional indications for adding LET at the time of primary ACL reconstruction include a Segond fracture seen on imaging, a lateral femoral notch sign on MRI, and concurrent meniscal surgery, high-level sports participation, and grade 2 or 3 pivot-shift findings. Meniscal root tears, total or subtotal meniscectomies, injury to the anterolateral soft tissue structures, and a posterior tibial slope greater than 12 degrees have all been shown to increase rotational instability — and therefore may tip the decision toward adding LET.

LET plays an even more prominent role when a previous ACL reconstruction has failed and revision surgery is required. In the setting of revision or primary ACL reconstruction with persistent anterolateral laxity — despite repair or reconstruction of other injured structures, or in the setting of increased tibial slope — a lateral extra-articular tenodesis procedure can be used to augment ACL reconstruction and aid in restoring anterolateral rotational stability while offloading stress on the new graft.

Strong evidence shows that an additional anterolateral stabilization procedure such as LET decreases the re-rupture risk after ACL reconstruction, which is especially important given that revision ACL surgery carries higher failure rates than primary surgery.

The addition of LET has been significantly associated with reduced odds of both asymmetric pivot shift and graft rupture. Adding LET was protective against re-tear, while younger age, greater posterior tibial slope, high-grade knee laxity, and earlier return to sport were associated with increased odds of graft rupture.