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How ACL (anterior cruciate ligament) surgery is done

What happens during ACL (anterior cruciate ligament) surgery

If you're having ACL (anterior cruciate ligament) surgery, you'll usually go into hospital on the day of the operation.

You may be asked not to eat or drink anything several hours before the operation.

Just before the operation, a healthcare professional will take you to the operating theatre.

You'll either have a general anaesthetic (you're asleep during the operation) or a local anaesthetic in your spine (you're awake but will have no feeling from the waist down).

The operation normally takes between 1 and 3 hours and you can usually leave hospital on the same day.

ACL surgery is usually done using a type of keyhole (arthroscopic) surgery, where only small cuts are made.

The main steps of keyhole ACL surgery are:

  1. The surgeon makes a small cut in the front of your knee and puts in a thin, flexible tube with a light and a camera at 1 end (an arthroscope) to check the ACL and look for damage to other parts of your knee.
  2. More small cuts are made for the surgeon to replace the torn ACL using a graft, usually taken from your hamstring.
  3. The graft is put in the same place as the damaged ACL and held in place with screws or staples. The screws or staples will be left inside your knee permanently.
  4. The surgeon checks your knee moves properly and the repair is strong enough.
  5. The surgeon closes the cut on your knee using stitches or clips, for example, and covers it with a dressing and bandage.
  6. After the operation, you'll stay in a recovery room until you're fully awake, where you may be given medicines to help with the pain.

Page last reviewed: 17 July 2025
Next review due: 17 July 2028