What is the problem?

A torn anterior cruciate ligament (ACL) can be reconstructed during surgery. The anterior cruciate ligament graft stabilises the knee but in less than 5% of cases, this graft can tear following another trauma with the risk of rendering the knee unstable again.

It is possible to carry out another anterior cruciate ligament reconstruction.

What examinations are necessary?

Immediately after the new sprain, knee x-rays need to be performed to rule out a joint fracture of which the initial symptoms are very similar to the rupture of an anterior cruciate ligament graft.

Once a fracture is ruled out, the patient must be examined by a doctor. A clinical examination immediately after a knee sprain is difficult due to the pain and thus needs to be reassessed two weeks later once the swelling has gone down and the pain receded. In most cases, the clinical examination is sufficient to diagnose an ACL graft tear. However, it is customary to perform a Magnetic Resonance Imaging (MRI) scan to confirm the rupture of the graft and highlight any other potential damage, especially to the menisci. Metal screws or staples may have been used during the primary ACL reconstruction to attach the graft. If this is the case, the metal may interfere with the MRI and thus make it impossible to interpret the images. A CT arthrogram can be requested instead.
The surgeon can also request other knee x-rays to assess any cartilage wear, which can modify the indication or the type of operation proposed.
Finally, the surgeon may request dynamic x-rays (TELOS) or a GeNouRoB® examination to assess anterior knee laxity caused by the anterior cruciate ligament graft tear.

What treatments are available?

Medical treatments, orthoses, and rehabilitation

The symptoms are often milder in the case of an ACL graft rupture than with the first sprain when the ACL ruptured.

The pain is treated with analgesics and anti-inflammatories. It is also recommended to put ice on the knee 4 to 6 times a day for the first few days following the trauma. If the knee is extremely taut and painful, the doctor may carry out a knee aspiration to drain the bruise and thus relieve the pressure inside the joint.

A rigid brace (orthosis) will also be worn of which the aim is twofold: to stop the knee giving way every time you put weight on it due to the quadriceps activation failure and to help the potentially torn lateral ligaments to heal at the same time as the anterior cruciate ligament.

Rehabilitation can begin early to recover joint range of motion and strengthen the quadriceps muscle.

When is surgery necessary?

An ACL graft tear may result in the the knee becoming unstable again, which can hamper sports and even daily life. The decision to carry out another ACL reconstruction depends on the patient’s functional impairment, age, and motivation to undergo another operation and commit to several months of postoperative rehabilitation.

It nevertheless seems preferable to propose such surgery to younger patients (age < 30 years), especially if there is repairable meniscal damage linked to the rupture of the ACL graft and this to prevent the onset of early osteoarthritis.

The operation proposed

Revision ACL reconstruction is proposed. This operation is technically more complex than the primary ligament reconstruction.

When is the best time to operate?

The best results are achieved when the ligament reconstruction is performed on a knee that has recovered from the sprain following rehabilitation sessions to reduce the swelling and recover normal mobility.

More rarely, the initial sprain is associated with a bucket handle meniscal tear causing the knee to lock during bending. In these circumstances, rehabilitation of the knee is not possible and the procedure must be performed rapidly to treat the meniscal tear at the same time as the ACL reconstruction and thus unlock the knee.

What are the risks if left untreated?

In the absence of surgery, there may be numerous consequences. The knee can become very unstable and it will be impossible to do some sports. Furthermore, the menisci may tear causing pain and even clicking of the knee. Ultimately, in the case of significant meniscal damage, osteoarthritis may develop.

The operation

If surgery is scheduled, the patient must consult an anaesthetist to determine the most appropriate anaesthesia with regard to the patient’s state of health. The anaesthesia will be either general (patient unconscious) or regional (spinal block) where only the lower part of the body is anaesthetised.

The operation takes place in an operating theatre in compliance with strict standards of cleanliness and safety. The patient is placed supine on an operating table and a tourniquet is placed around the thigh.

The main procedure: revision ACL reconstruction

  • Choice of tendon graft

The tendon graft used for this operation depends on the technique used for the primary ACL reconstruction. If the patellar tendon has already been harvested (Kenneth-Jones technique), the hamstring tendons (gracilis and semitendinosus) are used and vice versa.

In the case of reconstruction using the hamstring tendons (gracilis and semitendinosus), the tendon is harvested through a short incision of 2 centimetres on the anterolateral side of the leg, 5 centimetres below the knee.

In the case of reconstruction using the patellar tendon (Kenneth-Jones), the tendon is harvested through a vertical incision of 6 centimetres on the anterior side of the knee. The tendon can sometimes be harvested through two vertical incisions 2-3 centimetres each. The patellar tendon is harvested with two strips of bone, one from the patella and the other from the tibia.

  • Technical specificities of the operation

As with the first operation, the revision reconstruction is performed arthroscopically, a minimally invasive surgical technique that enables the operation to be carried out through small incision 5 millimetres in length located on the anterior side of the knee.

This second operation is more complex than the first reconstruction. The main technical difficulty stems from the fact that the bone tunnels in which the previous ligament grafts were attached are not always reusable and so new tunnels need to be created. This is not always possible straight away and in these more difficult cases it is necessary to fill the existing tunnels with a bone graft harvested in the pelvis then, a few months later, create the new tunnels in the correct positions. The tendon graft can then be attached.

Additional procedures

Revision ACL reconstruction is often combined with anterolateral ligament (LAL) reconstruction if this was not done during the primary ligament reconstruction. This additional procedure helps improve postoperative knee stability and requires an external incision of 5 centimetres to harvest a band located in the same zone called Fascia Lata of which the harvest is inconsequential.

In addition, any meniscal damage can be treated during the operation. The meniscus is repaired or the damaged part removed.

Before closing up, a drain (Redon) is often inserted in the incision to drain the blood and prevent the formation of a haematoma. This drain is generally removed just before the patient is discharged.

In general, the procedure lasts between 1 hour and 1 hour 30 minutes.
No blood transfusion is necessary for this operation.

After the operation

The initial pain is usually managed well with drugs or even a nerve block (placed in the operating theatre by the anaesthetist), which keeps the knee numb for several hours after the operation.

This operation is usually carried out during a short stay of fewer than 2 days, sometimes as outpatient surgery.

Weight-bearing is allowed from the outset but must be aided with crutches for 3 weeks. A knee brace is often used when going out for the first month after the operation. However, a brace is not necessary at home.

During the first month after the operation, you must reduce your level of activity. A nurse will visit you at home for the first three weeks to change the dressings and administer the anticoagulant injections.

Rehabilitation begins in the days following the operation. The initial aim is to wake up the muscles, help the swelling of the knee go down, and recover flexibility.

A check-up is scheduled one month after the procedure to assess recovery and progress made, as well as to adjust rehabilitation if progress is not as expected. Other check-ups are usually scheduled during the 3rd and 6th month after the operation.

You must remember that it is normal for your knee to remain swollen in the weeks following the operation. The pain will gradually fade over time and you will usually recover good knee function for daily life 6 weeks after the operation. However, this is an average and may take longer for some patients.

Resuming work and sport

The duration of medical leave depends on the patient’s profession and the type of operation but is usually between 1 and 3 months.

Sport can be resumed progressively. An exercise bike can be used soon after the operation. Running on flat ground (athletics track or treadmill) can be resumed from the 4th month and on any ground from the 6th month. Swimming with a flutter kick can also be resumed from the 3rd month. Most sports can be resumed after 6 months; however, particular caution must be taken with pivoting sports (football, ski, judo) for which it is necessary to wait until the 9th month.

The return to sport may differ depending on the additional procedures performed on the meniscus or cartilage.

Risks linked to the operation

Unfortunately, zero risk does not exist in surgery. Any operation has its risks and limitations, which you must accept or not undergo the operation. However, if an operation is proposed, the surgeon and the anaesthetist consider that the expected benefits far outweigh the risk incurred.

Some risks, such as microbial infections of the surgical site, are common to all types of surgery. Fortunately, this complication is rare but when it occurs requires another operation and a course of antibiotics. Bruising can also appear around the surgical site. This is usually prevented or reduced with a suction drain inserted at the end of the operation and removed in the days following the operation.
Knee surgery also increases the risk of phlebitis, which can lead to a pulmonary embolism. To minimise this risk, blood thinners (in the form of daily injections) are prescribed for 3 weeks following the operation.

In rare cases, the knee remains stiff, hot, and painful for several months after the operation. This complication, called algodystrophy or complex regional pain syndrome (CRPS), is unpredictable and sometimes takes a long time to heal.

Quite often, a small area of skin around the incision made to harvest the tendon or a larger area of the leg remains numb after the operation. This is caused by the stretching of the cutaneous branch of the internal saphenous nerve. Feeling is usually recovered within 6 months. More rarely, the loss of feeling persists but is not bothersome.

Finally, hypertrophic scar tissue (fibrosis) can appear at the site of the graft and can inhibit the total extension of the knee. This is called the Cyclops syndrome. It is often linked to problems with initial rehabilitation and may require another arthroscopy to remove the scar tissue and thus restore total knee extension. This complication is rare but must be verified with an MRI if it is suspected.

If you have any concerns about the operation, do not hesitate to talk to your surgeon or the anaesthetist and they will answer any questions you may have.

In Summary...

Who requires surgery?

Patients with an unstable knee or aged under 30 years, especially if there is also meniscal damage

Surgical technique


Which anaesthesia?

General or regional according to the patient’s history and wishes (determined with the anaesthetist)

Duration of hospitalisation

Short stay of 1 to 2 nights at the clinic

Resumption of weight-bearing

Immediate alleviated with crutches for 3 weeks

Duration of medical leave

1 to 3 months depending on the profession

Resumption of car driving

4 weeks after the operation

Resumption of riding a motorbike

3 months after the operation

Resumption of sport

Progressive from the 3rd month after the operation and from the 9th month for pivoting sports

Make an appointment

If you have any questions or wish to book a consultation,
please do not hesitate to contact us or make an appointment online via DoctoLib
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