Treatment : ACL surgery

What is the ACL and when is an ACL operation needed?

The ACL is located inside the knee joint and can be compared to an elastic band, when it is damaged, an ACL operation might be needed.

Why is it called "cruciate"?

There are actually two ligaments – the anterior cruciate ligament and the posterior cruciate ligament – that cross each other and work together to perform the same function: maintain the connection between the tibia and the femur, thereby stabilising the knee during flexion and extension movements or rotation of the leg.

Thus, the ACL prevents the tibia from moving or rotating too far relative to the femur, which would risk displacing the elements constituting the knee joint from their positions.

How do you know if your ACL is injured?

When the ACL is completely ruptured, an ACL reconstruction surgery may be required for patients to regain full usage of their knee.
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Depending on the type of anterior cruciate ligament injury, the symptoms and their intensity can vary. Mobility is significantly reduced due to pain in the knee. Patients often describe a sensation of the knee "giving way" when walking or changing directions.

Symptoms and Diagnosis

The knee will be unstable, painful, swollen, locked, and walking will be difficult. A quick medical consultation is crucial.

After an X-ray, a magnetic resonance imaging (MRI) scan will help to refine the diagnosis. This will confirm (or rule out) rupture of the ACL and look for the presence of other potential injuries such as meniscal tears or collateral ligament injuries.
The most common symptom of an ACL injury is that patients feel intense pain when the injury occurs. This can cause them to stop the activity immediately. A "pop" or cracking sound may also occur, indicating a more severe injury. The inflammation caused by the injury can lead to swelling around the knee within hours. In some cases, it is difficult to put weight on the affected leg.

Why ACL reconstruction surgery?

It is important to know that a ruptured ACL cannot heal on its own, even if the knee is immobilised. That’s why ACL reconstruction operation is essential. In many cases, the patient will have an unstable knee that gives way, hindering daily movements, preventing sports activities, and increasing the risk meniscal injuries in the future, damage to other ligaments, cartilage degradation, and eventually, osteoarthritis.

ACL tear surgery is necessary to remove the laxity, stabilize the joint, and restore full function. The surgeon will reconstruct your ACL and treat any secondary injuries.

What is an ACL reconstruction surgery?

A ruptured ACL can be treated using a reconstruction surgery for a torn ACL. You can refer to the knee exploration video here.

Just before the operation, the surgeon will check the exact anatomy of your knee and its injuries using ultrasound imaging. This will allow him to adapt the surgery by adding lateral reinforcement, for example.

An ACL knee surgery involves replacing the ruptured ligament. This can be done by minimally invasive surgery, using arthroscopy. A camera is inserted into the knee through a small incision to visualize the ruptured ligament. Through other small incisions, surgical instruments are used to take part of a nearby tendon and use it to replace the ruptured ligament.

The tendon graft is then inserted into two small bone tunnels drilled in the femur and tibia. The specialist knee surgeon then fixes this tendon with resorbable screws or cortical supports – a system that attaches the tendon graft to the hard part of the femur, called the cortex.

In most cases, a second stabilisation procedure is necessary to ensure optimal knee stability. This involves using the gracilis to stabilize the anterolateral aspect of the knee.

For practical information, watch the video "ACL and ALL Reconstruction Technique with Hamstrings Using Independent Graft" on YouTube.

During knee ligament reconstruction surgery, any meniscal injuries will be treated at the same time. The tendon from which the graft was taken will heal quickly on its own. For a torn ACL, this operation usually lasts 30 minutes and is performed as an outpatient surgery (entry in the morning and exit in the evening).

What techniques can be used?

After an ACL injury, the type of operation can vary. Indeed, there are several techniques for performing this surgery, including the STG and ST4 methods.

STG uses two tendons: semitendinosus and gracilis. This approach is more invasive as it involves harvesting two tendons, which may potentially weaken the hamstring muscles. In contrast, ST4 uses only the semitendinosus tendon, sparing the gracilis tendon. This has the advantage of weakening the hamstring muscles less, which facilitates the postoperative rehabilitation.

Other techniques include using the patellar tendon (Kenneth Johns), the quadriceps tendon, or even an allograft.

The choice depends on several factors, including the surgeon's preferences, the specific condition of the patient's knee, and expectations regarding recovery and return to sports. Professor Etienne Cavaignac will discuss the options with you and suggest which surgical technique he feels is best for your case.