Lateral Tenodesis (LET) and ALL Reconstruction with ACL Surgery

ACL reconstruction alone restores stability for the majority of patients. But some knees – particularly in young athletes returning to pivoting sport – have a worryingly high rate of re-rupture. The question I am asked most often in clinic is: "is there anything extra you can do to protect the graft?" In the right patient, the answer is yes.

Lateral extra-articular tenodesis (LET) and anterolateral ligament (ALL) reconstruction are procedures I perform alongside ACL reconstruction to improve rotational control and reduce the risk of re-injury. They are not appropriate for every ACL reconstruction – but when the risk profile warrants it, the evidence supports adding a lateral procedure.

Why rotation matters

The ACL prevents the shin bone sliding forward, but it also helps control knee rotation. Rotational stability is not the job of the ACL alone – structures on the lateral (outer) side of the knee contribute as well, including the anterolateral ligament (ALL).

When the ACL tears, these lateral structures are often stretched too. Even after a solid ACL reconstruction, some patients are left with residual rotational instability – the knee still "shifts" on pivoting, or the graft is under excessive rotational load every time they change direction. That is the problem LET and ALL reconstruction are designed to address.

When I add a lateral procedure

I do not add LET or ALL reconstruction routinely. I add it when the risk factors tell me the ACL graft needs protection. The clearest indications are:

High-grade pivot shift – if the knee demonstrates significant rotational laxity on examination, the ACL alone is unlikely to control it
Young athletes returning to pivoting/contact sport – football, rugby, netball, basketball, skiing – where re-rupture rates are highest
Generalised joint laxity or hypermobility – these patients put more load through every ligament, including the graft
Revision ACL surgery – if the first graft failed, I want to understand why and address rotational instability as part of the redo
Meniscus deficiency – loss of meniscal tissue reduces secondary stability, increasing the load on the ACL graft
Tibial slope or other anatomical risk factors – some knee shapes generate more rotational force than others

The decision is made in clinic by combining your examination findings, MRI, injury history, and what you need the knee to do. It is not a box-ticking exercise – it is a judgement call based on the overall risk picture.

LET versus ALL reconstruction

Lateral Extra-Articular Tenodesis (LET)

LET uses a strip of the iliotibial band (the tough fibrous tissue on the outer thigh) as a check-rein against excessive tibial rotation. I fix it to the lateral femoral condyle so that it tightens as the knee approaches the position where the pivot shift occurs. It is well-established, technically straightforward, and the evidence from the STABILITY trial and other studies is strong.

ALL reconstruction

ALL reconstruction places a graft along the anatomical course of the anterolateral ligament itself. Like LET, it controls internal rotation of the tibia and is performed alongside ACL reconstruction. I tend to use this approach when the ALL appears clearly damaged on MRI or when the anatomy suits a more anatomical reconstruction.

Both procedures achieve the same goal: reducing rotational laxity and protecting the ACL graft. The choice depends on the clinical scenario and what makes the most sense for that particular knee.

How I assess rotational instability

If you are being considered for ACL surgery with me, I assess rotational stability as part of the standard workup. The key elements are:

Pivot shift test – the single most important clinical test for rotational instability. I grade it from 0 to 3; a grade 2 or 3 shifts the conversation towards adding a lateral procedure
Overall laxity – I check the Beighton score and general joint flexibility
MRI – I look at the ACL, menisci, cartilage, and specifically the anterolateral structures for signs of injury
Sport and activity demands – a 19-year-old footballer returning to competitive pivoting sport is in a different risk category to a 40-year-old who wants to ski on holiday

If the assessment points towards a higher-risk knee, I plan the lateral procedure as part of the overall reconstruction – addressing meniscus injuries at the same time and building a rehabilitation plan around the combined surgery.

What happens during surgery?

I perform LET or ALL reconstruction at the same time as the ACL reconstruction, under the same anaesthetic. The procedure involves:

Reconstructing the ACL through standard arthroscopic (keyhole) techniques
Adding the lateral tenodesis or ALL graft through a small incision on the outer side of the knee
Checking stability and range of movement at the end to confirm the reconstruction is balanced

The additional lateral work typically adds 15–20 minutes to the operation. The incision is small – usually 4–5 cm on the lateral side of the knee.

Recovery and rehabilitation

Rehabilitation drives the outcome. The overall pathway is similar to standard ACL reconstruction, but the early phase is a little slower because the lateral soft tissues need time to heal.

Rehab priorities

Early swelling control and regaining full knee extension
Progressive quadriceps, hamstring, and hip strengthening
Neuromuscular training – landing mechanics, deceleration, change of direction
Graduated return to running when strength and control milestones are met
Return to sport based on objective testing (hop tests, strength ratios, movement quality) – not calendar dates

If I have also repaired a meniscus, the early phase is adjusted to protect the repair – this usually means restricted weight-bearing and limited flexion for the first few weeks.

Risks and considerations

Adding a lateral procedure is generally safe, but there are specific considerations I discuss with every patient:

Infection, blood clots, stiffness, swelling – the standard surgical risks
Lateral knee discomfort – some patients feel tightness or sensitivity on the outer side during early recovery. This almost always settles with time
Persistent instability – if the underlying problem is not fully addressed (for example a steep tibial slope, uncorrected alignment, or inadequate rehabilitation), instability can persist regardless of the lateral procedure

Frequently asked questions

Do I need a lateral tenodesis with my ACL reconstruction?

Not always. Most patients do very well with ACL reconstruction alone. I add LET or ALL reconstruction when the examination shows significant rotational laxity, or when the risk factors – age, sport, laxity, revision setting – suggest the graft needs additional protection.

Will adding a lateral procedure help me get back to sport?

It can improve rotational confidence and reduce the risk of re-rupture, which are both important for returning to pivoting sport. But the lateral procedure is only part of the picture – return to sport still depends on hitting rehabilitation milestones and passing objective testing.

Is LET only for revision ACL surgery?

No. I use it in primary ACL reconstruction when the risk profile justifies it – for example, a young pivoting athlete with a high-grade pivot shift and generalised laxity. It is also part of my standard approach in most revision ACL cases.

Can I be assessed for LET or ALL reconstruction in Bristol?

Yes. If you have an ACL injury and are considering surgery, I assess rotational stability as part of the standard evaluation and discuss whether a lateral procedure would benefit you.