Body > Common Knee Surgeries > ACL Reconstruction

ACL Reconstruction

An Anterior Cruciate Ligament (ACL) reconstruction is performed to restore knee joint stability.

A graft, usually from your hamstring tendons, is used to replace the damaged ligament. The graft is obtained through incisions at the front of your knee. The remainder of the surgery is done arthroscopically, with the aid of a telescope, and without actually opening the knee joint. This results in less pain and scarring within the knee post-operatively and ultimately a quicker recovery. As the hamstring tendon is used for the graft the hamstring usually feels sore for up to 6 weeks post-op.

The graft is fed through a tunnel drilled into the tibia (shin bone), across the knee joint and then into the femur (thigh bone). The graft is fixed at each end and is therefore initially very strong, allowing early movement and weight bearing on the leg.

Because the ACL graft has no initial blood supply, time is needed for the graft to establish its own blood supply. The graft loses strength during the first 6-8 weeks, and is at its weakest 6 weeks post-op. It is vulnerable at this time as the knee feels strong, but the graft is only beginning to establish its new blood supply. The graft does not have good blood supply until at least 10 weeks post-op. At 12 months post-op, the graft is 92% as strong as the original ACL, and this is as much strength as it develops.

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Exercises

  • After your knee operation it is very important to perform regular exercises to regain your mobility, and later strength.
  • Only perform exercises taught to you by your physiotherapist or surgeon.
  • Exercises should be performed 3-5 times a day.  It may be helpful to take pain medication 30-40 minutes prior to exercise (as prescribed by your doctor).
  • Schedule an appointment to see your physiotherapist 2 weeks after your operation.
  • Ensure your exercises are not too painful or cause more swelling. If there are problems contact your physiotherapist.

Swelling

  • You may have considerable swelling around your knee after surgery.
  • If this swelling persists it may impede healing and knee movement.
  • This can be treated by elevation, and applying ice for 20 minutes following exercises.
  • Ice (crushed, cubes, frozen peas, gel pack etc.) should be wrapped in a towel and placed directly on the knee.
  • Your physiotherapist can fit some compression stocking to your knee if necessary

Crutches

  • You will be asked to bring your own crutches prior to admission by your surgeon.
  • You are immediately allowed to place weight on the leg after your surgery – unless indicated otherwise by your surgeon or physiotherapist.
  • Make sure you stay active, attempting to walk on the leg as much as tolerated after the operation, ensuring the knee does not swell afterwards.

Splint

  • Depending on the type of surgery, you may have a splint on after your operation.
  • The splint is for comfort and protection.
  • It is safe to stop using it only when instructed by your physio or surgeon.
  • Your physiotherapist can show you how to put on and take off your splint after the operation.