Treatment of Ligament Injuries of the Knee

What are ligaments?

Ligaments are bands of tough, elastic connective tissue that surrounds a joint to give support and limit the joint’s movement. When ligaments of the knee are damaged, the knee joint may become unstable. Oftentimes ligament tears are a result of sports injuries.

There are 4 major ligaments in the knee. These ligaments connect the femur (thigh bone), to the tibia (shin bone).

  1. The anterior cruciate ligament (ACL):
    This ligament is in the centre of the knee, and it controls rotation and forward movement of the tibia (shin bone).
  2. Posterior cruciate ligament (PCL):
    This ligament is also located in the centre of the knee, but it controls backwards movement of the tibia (shin bone).
  3. Medial collateral ligament (MCL):
    This ligament gives stability to the inner side of the knee.
  4. Lateral collateral ligament (LCL): This ligament gives stability to the outer side of the knee.

Early treatment is normally referred to as RICE:


Ice pack application or cold packs to reduce swelling.

Compression with an elastic bandage or a brace.


Pain medication is normally given.

The medial collateral ligament is more often injured than the lateral collateral ligament and is normally a result of a force from the outer side of the knee like a rugby tackle. Usually most of the collateral injuries heal without the need for surgery. Between the cruciate ligaments, the ACL, is more commonly injured.

This is normally as a result of a twisting injury - where the foot is planted and the knee is twisted. This results in stretching or rupture of the ligaments. It is normally associated with sports, like netball, basketball, rugby, and soccer.

The PCL is normally injured by a backward force on the lower leg like car accidents, or a full on, or straight on tackle.

Following the initial treatment, the ligament injury might be treated by a protective knee brace, limitation of activities and referral to a physiotherapist to start strengthening of the muscles.

With this treatment, surgery is often not necessary, and most people can return to their activities without any problems.

Surgery to treat ligament injuries of the knee is normally reserved for complete tears of the ligaments and for people with ongoing instability of the knee where the knee gives way with normal activities and during sports.

The surgery to address the torn knee ligament, normally involves replacing the torn ligament with a healthy tendon. This is usually a tendon taken from the patient (autograft) and the most used tendons are hamstring tendons or tendons around the kneecap. In special circumstances a tendon graft can be from an organ donor (called an allograft)

What are the Risks of Knee Ligament Repair?

Although surgery to reconstruct knee ligament injuries is normally safe and effective, complications can occur as with any surgical procedure.

General risks of surgery:

  • Surgery to repair ligaments is usually done using general anaesthesia when a patient is put to sleep. Unexpected death from an anaesthetic is very rare.
  • Antibiotics are routinely used during surgery to prevent infection – some patients may have an allergic reaction or anaphylaxis.
  • Wound infection.
  • Bleeding in the wound with haematoma (big collection of blood) formation.
  • Pain / numbness around the incision.
  • Allergies to antiseptic solutions used to clean the surgical site.
  • Allergies to sutures and / or dressings.
  • Deep vein thrombosis – there is always a risk of DVT with surgery of the lower limb.
  • Nausea and vomiting after surgery.

Specific Risks with ACL Surgery:

  • Surgery is performed using a tourniquet around the thigh. You might experience pain and bruising in the area.
  • During harvesting of the donor tendon, the tendon can snap. If this happens, an additional tendon might need to be harvested from the same or the other knee.
  • Injury to a nerve.
  • Injury to blood vessels.
  • Persistent pain in front of the knee.
  • Stiffness of the knee happens in about 3 – 5% of people – this might need further surgery.
  • The operation may not work, and the knee might continue to feel loose, despite a healthy graft.
  • Ongoing swelling and grinding noises.
  • The graft can rupture like a normal ligament if you have another injury.
  • There is a risk of developing “wear and tear” arthritis down the line.

Recovery after ACL Surgery:

Following reconstruction of your cruciate ligament, you will wake up in the recovery room. You may have a knee brace applied to your knee.

The nurses in the recovery room will monitor your recovery by doing the vital signs (pulse, blood pressure etc). Once you get to the ward, and ice pack may be applied to your knee to help with pain and swelling. Most people are able to be discharged the next day. Make sure that you arrange for somebody to pick you up and take you home.

When you get home, you will need to continue with elevation of the leg, application of ice packs for 30 minutes periods, 4 –
6 times a day. You will need to continue to use crutches and a knee brace for a while. You will be discharged home with

strong pain medication. Try to only use the stronger pain medication, if regular pain medication like paracetamol is not effective.

It is important to keep the surgical area clean and dry and to keep the wound dressings intact.

You will be supplied with a follow-up date for removal of sutures and a wound review.

A physiotherapist will see you in hospital and will supply you with some initial exercises. It is important for you to book an appointment with a physiotherapist of your choice to continue with your rehabilitation.

Recovery after surgery is different for every patient. It is important to avoid any twisting or sideways movement initially. You will be able to start cycling around 6 – 8 weeks after the surgery. You will be advised when you can assume normal activities. Usually, it will take around 6 – 12 months to return to twisting sports.

Please contact the surgery immediately if you have any of the following:

  • Any redness, swelling, bleeding or drainage from your incision site.
  • Any fever or chills.
  • Any increase in pain around the incision site.
  • Any pain in your calf or thigh with increased swelling in the leg.


Please find links to some useful information below:

You can also follow the link to a wonderful animation of an ACL repair:

ACL Repair