Dr. David Liu: 07 5598 0205
Dr. Haig Lennox: 07 5598 0531
Dr. Sonja Schleimer: 07 5598 0094
Dr. Michael Facek: 07 5611 5050

Anterior Cruciate Ligament (ACL) Reconstruction

The Anterior cruciate ligament is one of the four major ligaments of the knee that connects the femur (thigh bone) to the tibia (shin bone) and helps stabilize your knee joint. It is a strong rope like structure located in the centre of the knee. It prevents excessive forward movement of the lower legbone (the tibia) in relation to the thigh bone (the femur) as well as limiting rotational movements of the knee.

When this ligament tears, usually following an injury, it does not heal. An ACL deficient knee may lead to a sense of instability, usually with twisting and pivoting type manoeuvres. Repetitive subluxations may result in further injuries to the knee e.g. Meniscal and chondral injuries.

ACL reconstruction is a commonly recommended and performed surgical procedure. With recent advances in arthroscopic surgery, it can now be performed with small incisions, minimal morbidity and low complication rates. Options for reconstruction are hamstring tendons, patella tendon or less frequently allograft or synthetic material. Repairs (suturing the ACL) are rarely performed in adults and have unpredictable results.

ACL Reconstruction Procedure

  • Performed in theatre under anaesthetic
  • Usually performed arthroscopically
  • Knee assessed arthroscopically and other injuries assessed and managed
  • Surgeons choice of auto-graft (hamstring or bone patella tendon bone) is harvested
  • Less commonly and in specific scenarios, allograft or synthetic material is used
  • Special surgical instrumentation and on occasions X-rays are used to guide tunnel position into the femur and tibia
  • The graft is passed into the knee and stabilised in both bony tunnels with a variety of implant options
  • The knee is assessed for stability and range of movement
  • On occasions, additional ligaments are reconstructed to control persistent rotatory instability (Antero-lateral or Postero-lateral corners)
  • The incisions are closed with sutures and a dressing applied

Post-operative care

  • Usually overnight hospital stay
  • May require hinge knee brace if associated meniscal surgery performed
  • Usually partial weight bear with crutches till confident ~1-2 weeks
  • Recommend regular icing in the first week
  • Pain control may require patient controlled analgesia (PCA)
  • Depending on the risk profile of the patient, anticoagulants may be prescribed
  • The patient will be supplied and instructed in basic exercises to perform at home prior to the 2-week follow-up. Formal physiotherapy will commence after 2 weeks
  • Water therapy is encouraged after wound healing ~ 2 weeks

Goals and Outcomes

The aim of the reconstruction is to restore functional stability of the knee to allow patients to return to pre-injury sport and activity with confidence and no pain.

Reconstructions are good operations when performed correctly and when post-operative rehabilitation is diligently performed. Patients should avoid pivoting and contact sports for 6-9 months following biological reconstructions.

There is always the risk of re-rupture of the ACL (~10%), particularly when returning to contact sports. Re-rupture is higher if rotatory instability is not corrected at the time of surgery.
Outcomes are less predictable in patients with associated cartilage, meniscal or other knee ligament injuries.

Risks and complications

Possible risks and complications associated with ACL reconstruction include:

  • Anaesthetic complications
  • Blood clots(Deep vein thrombosis/Pulmonary embolus)
  • Numbness around scars and lower leg
  • Infection
  • Persistent instability
  • Persistent knee swelling
  • Nerve and blood vessel damage
  • Failure of the graft or the fixation of the graft
  • Decreased range of motion or stiffness
  • Crepitus (crackling or grating feeling of the kneecap)
  • Pain in the knee or anterior (Bone patella tendon bone)
  • Repeat injury to the ACL graft

The patient is a very important part of the pathway pre and post surgery. Patients need to be responsible for there own health and follow treatment instructions. Informing the doctor or appropriate professional if there is a concern. Early diagnosis and treatment of complications will improve the success of treatment.

Anterior Cruciate Ligament (ACL) Reconstruction