ACL Reconstruction & Repair

Introduction

The anterior cruciate ligament is one of the major stabilising ligaments in the knee. It is a strong ‘rope-like’ structure located in the centre of the knee attaching the femur (thighbone) to the tibia (shinbone).

When this stabilising ligament tears, it unfortunately fails to heal anatomically and often leads to instability of the knee joint.

ACL reconstruction to restore stability is a commonly performed surgical procedure and with recent advances in arthroscopic surgery can now be performed with minimally invasive incisions and low complication rates.

Function

The ACL is one of the major stabilizing ligaments in the knee. It prevents the tibia (shinbone) moving abnormally underneath the femur (thighbone). When this abnormal movement occurs, it causes instability and the patient may well be aware of this abnormal movement as the knee may collapse.

Often other structures, such as the meniscal cartilage (shock absorber), the articular cartilage (lining of the joint) or other ligaments may be damaged alongside an ACL injury and these may need to be addressed at the time of surgery.

History of Injury

Most injuries are sports related involving a twisting injury to the knee
It can occur with a sudden change of direction, a direct blow e.g., a tackle or landing awkwardly from a jump
Often there is a ‘popping’ sound when the ligament ruptures
Swelling usually occurs shortly after the injury
There is often the feeling of the knee collapsing or ‘slipping’ out of joint
It is rare to be able to continue playing sport after the initial injury

Once the initial injury settles down, the main symptom is instability or ‘giving-way’ of the knee. This usually occurs with twisting activities but can occur on simple walking or other activities of daily living.

Diagnosis

The diagnosis can often be made on the history alone.

Examination reveals instability of the knee, if adequately relaxed and not too painful.

An MRI (Magnetic Resonance Imaging) can be helpful if there is doubt as well as to look for damage to other structures within the knee.

More rarely, the final diagnosis can only be made after an examination under anaesthetic or with an arthroscopy.

Initial Treatment

Rest
Ice
Elevation
Bandaging

Long term

Some people can compensate for the injured ligament with strengthening exercises may be able to avoid the need for reconstruction. If the knee remains unstable, the evidence from scientific literature is that there is an ongoing and cumulative risk of further damage to the rest of the joint.

Episodes of instability can cause further damage to important structures within the knee that may result in early arthritis

Indications for surgery

patients wishing to maintain an active lifestyle.
Sports involving twisting activities e.g., Football, rugby, netball,

Giving way with activities of daily living.
People with active occupations e.g., Policemen, firemen, roofers, scaffolders.
It is advisable to have physiotherapy prior to surgery to regain motion and strengthen the muscles as much as possible.

Surgery

Surgical techniques have improved significantly over the last decade, complications are reduced and recovery much quicker than in the past. Mr Frame uses a minimally invasive technique called the Arthrex All Inside. This uses only one hamstring tendon instead of 2, reducing pain and maintaining your leg strength.

The surgery is performed arthroscopically. The ruptured ligament is removed and then small sockets rather than full traditional tbone tunnels are created in the bone to accept the ACL graft.

The graft is prepared to take the form of a new tendon and passed through one of the small keyhole incisions and in to the sockets.

The new tendon is then fixed into the bone with small titanium buttons rather than large traditional screws to hold it in place while the ligament heals into the bone (usually 3-6 months).

The rest of the knee can be clearly visualised at the time of surgery and any other damage is dealt with e.g., meniscal tears.

The wound is then closed and a dressing is applied.

Post-operation

Surgery is performed as a day-case procedure or an overnight stay.

You will have pain medication by tablet or in a drip (intravenous). Your anaesthetist may suggest a nerve ‘block’.

You will be seen by a physiotherapist who will teach you to use crutches and show you some simple exercises to do at home.

Leave any waterproof dressings on your knee until your post-op review.

You can put all your weight on your leg.

Put ice packs on the knee for 20 minutes at a time, as frequently as possible.

Your first post-op review will usually be at 12-14 days.

Physiotherapy will begin immediately.

If you have any redness around the wound or increasing pain in the knee, if you have a temperature or feel unwell, you should contact your doctor as soon as possible.

Risks & Complications

Complications are not common but can occur. Prior to making the decision to have this operation, it is important that you understand these so that you can make an informed decision regarding the advantages and disadvantages of surgery.

These can be Medical (Anaesthetic) complications and surgical complications

Medical (Anaesthetic) complications

Medical complications include those of the anaesthetic and your general wellbeing. Almost any medical condition can occur, so this list is not complete. Complications include

Allergic reactions to medications

Blood loss (potentially requiring transfusion with its low risk of disease transmission), heart attacks, strokes, kidney failure, pneumonia, bladder infections/urinary retention. Complications from nerve blocks such as infection, pain or nerve damage resulting in numbness and weakness. Serious medical problems can lead to ongoing health concerns and prolonged hospitalisation.

The following is a list of surgical complications. These are all rare but can occur. Most are treatable and do not lead to long term problems.

Infection

Approximately 1 in 200. Treatment involves either oral or antibiotics through a drip, or rarely, further surgery to wash the infection out.

Deep vein thrombosis

These are clots in the veins of the leg. If they occur, you may need blood thinning medication in the form of injections or tablets. Very rarely, they can travel to the lung (Pulmonary Embolism) which can cause breathing difficulties or even death.

Excessive swelling & Bruising

This can be due to bleeding in the soft tissues and will settle with time.

Joint stiffness

Can result from scar tissue within the joint and is minimized by advances in surgical technique and rapid rehabilitation. Full range of movements cannot always be guaranteed.

Graft failure

The graft can fail in the same way as a normal cruciate ligament can. Failure rate is approximately 5%. If the graft stretches or ruptures it can still be revised if required using alternative graft material (sometimes from the other leg).

Damage to nerves or vessels

These are small nerves under the skin which cannot be avoided and cutting them can lead to an area of numbness in the leg. This normally reduces in size over time and does not cause any functional problems with the knee. Very rarely there can be damage to more important nerves or vessels causing weakness/numbness in the leg.

Hardware problems

All grafts need to be fixed to the bone using various devices (hardware) such as screws or staples. These can cause irritation of the wound and may require removal when the graft has grown into the bone.

Donor site problems

‘Donor site’ means where the graft is taken from. In general, either the hamstrings or patella tendon are used. These can include pain or swelling in these areas which usually resolves over time. A subtle loss of function is not usually noticed.

Residual pain

Can occur especially if there is damage to other structures inside the knee

Complex Regional Pain Syndrome

An extremely rare condition that is not entirely understood, which can cause unexplained and excessive pain.

Summary

Anterior Cruciate Ligament reconstruction is a common and very successful procedure. If your surgery is carried out by experienced knee surgeons, such as Mr Frame, who perform a lot of these procedures, 95% of people have a successful result. It is generally recommended in a patient wishing to return to an active lifestyle especially those wishing to play sports involving running and twisting.

The above information has hopefully educated you on the choices available to you, the procedure and the risks involved. If you have any further questions you should consult with Mr Frame.