Anterior Cruciate Ligament (ACL) Reconstruction - Orthopaedic Surgery

Complete ACL tears cannot be stitched back together and a tissue graft taken from another location in the body is used, hence why the surgery is called a reconstruction and not a repair. The surgery involves making a small incision and inserting a small camera, an arthroscope, to examine the inside of the knee and check that ACL is torn as well as look for damage to other parts of the knee. The remnants of the torn ACL are removed with keyhole surgery and tunnels are then made in the femur and tibia bones to allow the graft to be positioned across the knee. The new reconstructed ligament is then fixed at both ends with screws or staples to secure it in place and the incisions are stitched up. The operation takes somewhere from 1 hour to 1 1/2 hours and the success rate is 90-95%.

The most important decision the patient makes is deciding which tissue the surgeon will use to take the tissue graft from, as this is the tissue that will replace the ACL. There are multiple options and the surgeon will discuss which is the best option for the patient. These include:

• A strip of the patellar tendon - the tendon connecting the bottom of the kneecap to the top of the shinbone at the front of the knee.
• A part of the hamstring tendons - the tendon running from the back of the knee on the inner side, all the way up to the thigh.
• A part of the quadriceps tendon - the tendon attaching the kneecap to the quadriceps muscle on the front of the thigh.
• An allograft (donor tissue) - the patellar tendon or Achilles tendon from a donor.
• A synthetic graft - a tubular structure designed to replace a torn ligament. These are currently only used in certain situations such as revision surgery (a surgery to fix mistakes made in a previous surgery).

The first three options are all autograft tissues - these tissues come from elsewhere in the patient's body and all have strong success rates. The different tissues have different results such as some studies showing the hamstring tendon replacement to result in less pain after surgery than the patellar tendon but conversely that the patellar tendon replacement to have a higher success rate.

An allograft (donor tissue) tissue may be the preferred option for people who are not going to be playing high-demand sports, such as basketball or football, as these tissues tend to be slightly weaker and have a higher failure rate. These tissues are treated before being selected for use in reconstruction to minimise the chance the patient's body rejects the tissue.

There are two options regarding anaesthetic choice for this procedure; a general anaesthetic or a spinal anaesthetic. The patient is asleep under general anaesthesia and feels no pain while they are awake but feel no pain under spinal. There are studies that suggest that rates of complications and mortality are lower under spinal anaesthesia than under general anaesthesia but the risks under either are very low.

After the surgery the knee is bandaged, pain-relieving medication may be given, and the patient may be given a Cryo/Cuff to wear on the knee. This is a waterproof bandage that contains iced water to reduce the swelling in the knee. Painful bruising, swelling and redness down the front of the shin and ankle, caused by the fluid inside the knee joint and blood leaking down the shin are common in the first weeks after the surgery however, these are temporary and should start to improve after a week. The surgeon will advise about the post-operation plan based on the patient and the usual full recovery time is 8-12 months.

The time to return to work depends on the type of work they do; if they work in an office they could potentially return to work after 3 weeks but if manual labour is involved then it could be up to 3 months until they can return to work. Driving is usually possible again after 4 weeks or after they can comfortably put weight on the foot.