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Anterior cruciate ligament (ACL) reconstruction is a type of knee surgery to replace your ACL – one of the main ligaments in your knee. Your ACL connects your thigh bone to your shin bone, and along with other ligaments in your knee, keeps your knee stable. You may need surgery if you have an ACL injury (your ligament is torn or sprained).


Why would I need an ACL Reconstruction?

If you have an ACL injury and your knee is unstable (it gives way), ACL reconstruction may be an option for you. Not everyone with an ACL injury needs surgery. Your doctor or surgeon will go through your treatment options and explain what would work best for you. However, there are certain situations when surgery is more likely to be recommended. These include if you:

  • play sports that include a lot of twisting and turning – such as football or basketball, to a high level – and you want to get back to it

  • have a very physical or manual job, for example you’re a firefighter, police officer or work in construction

  • have damage to other parts of your knee, which could also be repaired with surgery


Preparing for ACL Reconstruction

Your surgeon is likely to delay surgery until any swelling has gone down and you’ve regained near-to-full range of movement in your knee. This might be within a couple of weeks after your injury, but it varies from person to person. You’re likely to be asked to follow a preoperative rehabilitation programme during this time. This usually involves specific physiotherapy exercises designed to strengthen your leg muscles and improve your range of motion. It also incorporates more general light activities such as walking and swimming.

Your surgeon will explain what else you need to do to prepare for your operation. For example, if you smoke, you’ll be asked to stop because it increases your risk of getting a chest and wound infection, and slows healing time.

You’ll usually have the surgery as an out-patient (you won’t need to stay overnight), and you may have it under general or spinal anaesthesia. If you have a general anaesthetic, this means you’ll be asleep during the operation. With a spinal, you’ll stay awake but the lower part of your body will be numb. You’ll need someone who can drive you home after your operation and stay with you overnight.

If you're having a general anaesthetic, you’ll need to stop eating and drinking for a set amount of time before your surgery. This is usually for around six hours before your operation, but you should be able to drink water up to two hours before. Follow your anaesthetist/doctor's advice and if you have any questions, just ask.

On the day of your procedure, your surgeon will meet with you to check you are well and still happy to go ahead. The staff at the hospital will do any final checks and get you ready for surgery. This may include asking you to wear compression stockings, or having an injection of an anticlotting medicine to help prevent deep vein thrombosis (DVT).


What happens during an ACL Reconstruction?

ACL reconstruction is usually done by keyhole or arthroscopic surgery, meaning it’s carried out through several small cuts into your knee. Once the anaesthetic has taken effect, your surgeon will make these cuts in the skin over your knee. They’ll use an arthroscope – a thin, flexible tube with a light and camera on the end of it – to see inside your knee.

The surgery involves replacing your torn ligament with a graft, which your surgeon will take first. The graft is usually a piece of tendon from another part of your knee, for example:

  • hamstrings, which are tendons at the back of your thigh

  • the patellar tendon, which holds your kneecap in place

Sometimes, a graft from a donor may be used. This is called an allograft and will be collected before your surgery. You can find out more about grafts used in ACL reconstruction in our FAQs below.

Your surgeon will then drill a tunnel through your upper shin bone and lower thigh bone. They’ll thread the graft in through the tunnel and fix it in place, usually with screws or staples. Before finishing the operation, your surgeon will make sure there is enough tension on the graft and that you have full range of movement in your knee. Then they’ll close the cuts with stitches or adhesive strips.

Your operation will usually last between one and three hours.

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What to expect afterwards

You’ll need to rest until the effects of the anaesthetic have passed. You’re likely to have some pain, stiffness and discomfort as the anaesthetic wears off, but you'll be offered pain relief as you need it.
You’ll be encouraged to get up and move around, and to put weight on your leg as soon as possible. You may be given crutches and a knee brace to help support you.
This operation is usually done as an out-patient procedure. This means you’ll be able to go home once the anaesthetic has worn off. However, you’ll need someone who can drive you home and stay with you overnight.
You’ll have dressings over the wounds around your knee. Before you go home, you’ll be given some advice about caring for your healing wounds, signs of infection to look out for and pain relief you can take at home. You’ll also be given a date for a follow-up appointment.
Having a general anaesthetic can really take it out of you. You might find that you're not so co-ordinated or that it's difficult to think clearly. This should pass within 24 hours. In the meantime, don't drive, drink alcohol, operate machinery or make any important decisions.


Recovering from an ACL Reconstruction

It usually takes about six months to a year to make a full recovery from ACL reconstruction. You’ll see a physiotherapist within the first few days after your operation, who will give you a rehabilitation programme to follow with exercises specific to you. These will depend on many things, including the extent of the damage to your knee and the level of activity you’re hoping to get back to.

Following your rehabilitation programme will help you get your full strength and range of motion back in your knee. Many people are able to progress to walking without crutches within about two weeks after surgery. It usually takes about six to nine months to be able to go back to playing sport. This varies from person to person though and will depend on the sport you play and how well you’re recovering. Some people wear a knee brace when they return to playing sport. However, they can be bulky and awkward to wear. You don’t need to wear one – it doesn’t seem to make a difference to how well your knee functions. But you might find that it helps build your confidence as your knee will feel supported.

During your recovery, you can take over-the-counter painkillers such as paracetamol or anti-inflammatory medicines such as ibuprofen. Make sure you read the patient information that comes with your medicine and if you have any questions, speak to your pharmacist for advice. You can also apply ice packs (or frozen peas wrapped in a towel) to your knee to help reduce pain and swelling. Don't apply ice directly to your skin though, as it can damage it.

Your surgeon will be able to advise you about when you can return to work, driving, and other activities.

Information from BUPA UK

The content is intended for general information only and does not replace the need for personal advice from a qualified health professional.

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