Updated: we now have a full, illustrated guide to this operation — see Lateral Extra-Articular Tenodesis (LET) for the technique, the evidence and who benefits.
Why Do ACL Grafts Fail?
While ACL reconstruction is a generally successful procedure, graft re-rupture remains a significant concern. The reasons for graft failure are multifactorial and typically involve factors such as the type of graft used, technical aspects of the surgery, or a traumatic re-injury.
The anterior cruciate ligament (ACL) is crucial for providing stability to the knee, particularly with regard to:
- Front-to-back motion (sagittal plane)
- Rotational control
It is important to note that rotational control of the knee is not solely provided by the ACL. Other structures, such as the iliotibial band (ITB) and Kaplan’s fibers on the outer knee, also play a significant role in rotational stability. Additionally, the meniscus within the knee contributes to overall knee stability.
When ACL reconstruction is performed without addressing damage to these additional stabilizing structures, the risk of graft failure increases.
Patient-related factors also influence graft success. For instance, individuals with hyperlaxity (increased joint flexibility) may place more stress on the ACL graft, potentially leading to failure. Similarly, patients with a significant tibial slope may experience additional strain on the graft.
Over time, it has become increasingly clear that ACL reconstruction involves more than just repairing the ACL itself. A comprehensive approach that takes into account the involvement of other knee structures and individual patient factors is essential for minimizing the risk of graft failure.
What is a Lateral Tenodesis?
Lateral tenodesis is an additional surgical procedure that can be performed during ACL reconstruction to enhance knee stability. It involves harvesting a strip of tissue (about 1 cm thick and 8–10 cm long) from the iliotibial band on the outer side of the knee. This tissue is then re-routed beneath the lateral collateral ligament, which acts as a pulley, helping to better control rotational movement at the knee.
Is There Evidence Supporting This Procedure?
Yes, recent high-quality studies have demonstrated that lateral tenodesis significantly reduces the risk of ACL graft re-rupture in younger patients, particularly those who undergo ACL reconstruction using a hamstring graft. In one study, the re-rupture rate dropped from 11% to 4% in this patient group.
Are There Any Drawbacks?
As with any procedure, lateral tenodesis has potential drawbacks. It adds an extra incision on the outer side of the knee and may cause some additional pain in the first few months after surgery. However, by 12 months post-surgery, the pain typically resolves, and there is no significant difference in long-term outcomes compared to ACL reconstruction without lateral tenodesis.
Does Everyone Need a Lateral Tenodesis?
No, not every patient undergoing ACL reconstruction requires a lateral tenodesis. The procedure is typically recommended for patients who meet specific criteria, including:
- Young age (under 25 years)
- Hyperlaxity (increased joint flexibility)
- Professional Athlete
- Female patient who participates in pivot sports i.e football, netball, and skiing
- Clinical signs of poor rotational control (such as a positive pivot shift test)
- Revision ACL surgery
In Summary
Lateral tenodesis is a valuable adjunct to ACL reconstruction, particularly for patients at higher risk of graft failure. By enhancing rotational stability, it has been shown to reduce the likelihood of graft re-rupture, offering an added layer of protection for patients undergoing ACL reconstruction.
References:
- Kittl C, El-Daou H, Athwal KK, et al. The Role of the Anterolateral Structures and the ACL in Controlling Laxity of the Intact and ACL-Deficient Knee. Am J Sports Med. 2016;44(2):345-354. doi:10.1177/0363546515614312
- Getgood AMJ, Bryant DM, Litchfield R, et al. Lateral Extra-articular Tenodesis Reduces Failure of Hamstring Tendon Autograft Anterior Cruciate Ligament Reconstruction: 2-Year Outcomes From the STABILITY Study Randomized Clinical Trial. Am J Sports Med. 2020;48(2):285-297. doi:10.1177/0363546519896333