ACL Reconstruction

What is an ACL reconstruction?

ACL reconstruction surgery is a procedure used to rebuild or repair a torn anterior cruciate ligament (ACL) in the knee. The ACL is one of the major ligaments that helps stabilise the knee joint. ACL injuries are common, especially among athletes, and can result from sudden twists, changes in direction, or direct impacts during sports such as football, rugby, or skiing.

ACL reconstruction surgery is usually recommended when the ligament is torn, causing instability and pain, particularly when trying to pivot or perform sports activities.

When is an ACL reconstruction recommended?

An ACL tear can cause the knee to feel unstable, often described as a "giving way" sensation. Without a functioning ACL, activities that involve pivoting, turning, or sudden stops become difficult, and patients may experience pain, swelling, and limited movement.

Surgery is often recommended in cases where:

• The knee is unstable and affects daily activities
• The patient is an athlete or physically active and wishes to return to sports
• Non-surgical treatments like physiotherapy have not resolved symptoms
• The injury involves damage to other parts of the knee, such as the meniscus

In cases where the patient is less active or can manage with lifestyle adjustments, non-surgical treatment like physiotherapy may be an option.

Preparing for ACL surgery

Before undergoing ACL surgery, patients will have an assessment with an orthopaedic surgeon. This includes physical examinations and imaging, such as MRI scans, to assess the extent of the damage. Patients are often required to undergo physiotherapy before surgery to strengthen the knee and restore as much function as possible. This prehabilitation can help with recovery after the procedure.

Patients may also be asked to stop taking certain medications, such as anti-inflammatories or blood thinners, prior to the surgery to minimise the risk of bleeding. A discussion regarding the use of a graft (tissue used to replace the torn ligament) will take place, as this tissue can be taken from the patient’s own body (autograft) or from a donor (allograft).

What does the procedure involve?

When patients arrive at the hospital, they will meet a nurse, the anaesthetist and their surgeon. ACL reconstruction is typically performed as a keyhole procedure is typically performed under general or spinal anaesthesia. The surgeon makes small incisions around the knee and inserts a camera (arthroscope) to view the damaged area.

The torn ACL is replaced using a graft, which is secured in place with screws or other fixation devices. The graft acts as a scaffold for new ligament growth. Once the repair is complete, the small incisions are closed with stitches or surgical tape, and a dressing is applied to the knee.

The procedure generally takes 1 to 2 hours, and most patients can go home the same day, though in some cases, an overnight hospital stay may be required.

What are the potential risks and complications?

While ACL reconstruction is generally successful, like all surgeries, it carries some risks. These include:

• Infection at the surgical site
• Blood clots in the legs (deep vein thrombosis)
• Stiffness or loss of range of motion in the knee
• Failure of the graft (rare but may require further surgery)
• Nerve damage around the knee (temporary or permanent)
• Ongoing knee instability or pain despite surgery

The surgeon will discuss these risks before the operation and provide advice on how to minimise complications during recovery.

After the procedure

Recovery from ACL reconstruction can take several months, and  requires commitment to physiotherapy and rehabilitation exercises. Immediately after surgery, the knee may be swollen and sore, but pain relief will be provided. Patients are usually advised to keep the leg elevated and to apply ice to reduce swelling in the first few days.

The use of crutches is typically required for 1 to 2 weeks to aid walking without putting too much weight on the knee. A knee brace may also be provided to keep the joint stable.

Physiotherapy begins soon after surgery and is essential for restoring strength, range of motion, and stability to the knee. Most patients can resume light activities within 3 to 6 months, but returning to sports can take 9 to 12 months, depending on the extent of the injury and individual recovery progress.

ACL reconstruction is highly effective in restoring stability and function to the knee, particularly for active individuals who wish to return to sports or physically demanding activities. A successful outcome depends on following a structured rehabilitation programme and adhering to the physiotherapist’s instructions.

In the long term, most patients regain full function and can resume their normal activities. In some cases, there may be a risk of osteoarthritis developing in the knee later in life, particularly if the injury involved damage to other structures in the knee.