Anterior cruciate ligament reconstruction

Introduction

Ruptures of the anterior cruciate ligament are common sporting injuries. It results in painful instability, loss of mobility in the knee, makes it difficult to continue to play sport and possibly increases the chance of later developing arthritis in the knee joint.

Indications

Reconstruction is indicated when the knee has become unstable from the loss of function of the normal ligament after injury. This is a very common operation for a common condition.

Pre-operative instructions

It is essential to the success of this operation that you prepare your knee beforehand. You will need to work with your physiotherapist to regain your normal range of motion in the knee. Having strong muscles aids your rehabilitation as well.

Procedure

Anterior cruciate ligament reconstruction is an arthroscopic procedure. We use the hamstring tendons as the graft (and only very rarely these days the middle third of the patella tendon). We never use artificial ligaments due to risks of post-operative synovitis. The graft is fixed with screws into the bony tunnels in the tibia and femur. Although this is a very good method of fixation you will not be able to weight-bear on the knee for at least the first two weeks. The reason for this approach is to allow the graft to fix itself on the bone. Premature weight-bearing can slide the graft out of the tunnel and results in laxity in the knee the very thing we are trying to overcome. There is very little pain from the donor site and you will probably not notice any loss of knee flexion power after removing the two hamstring tendons as the remaining tendons function normally. Generally, you can go home on the day of surgery.

Post-operative instructions

No brace is required and you can move the knee immediately. If you can fully extend your knee by the first post-operative visit, you will be able to take weight on the leg as long as the knee is held in full extension. You can walk with a more normal stride at about the fourth post-operative week and this is when we start you on your physiotherapy. The recovery of your range of motion is dependent on the correct isometric positioning of the graft as much as your efforts at mobilisation. You will be seen by very experienced physiotherapists who will adjust their efforts to match your progress. You can expect to regain normal stability and a full range of motion by about six-week post-operative. By then, your knee will be comfortable enough to engage in some vigorous training to strengthen your quads and hamstring muscles.

Risks

As this is a minimally invasive procedure the risks are reasonably small but do exist. You may develop a blood clot or even an infection in the joint. These problems are exceedingly rare.

Treatment alternatives

Once the anterior cruciate ligament is ruptured and your knee remains unstable it is not possible to regain the stability by just training your muscles so there is no non-surgical alternative to deal with this form of knee instability.

Related Information

Anterior cruciate ligament injuries