The anterior cruciate ligament (ACL) is one of the main stabilisers of the knee joint.
When then ACL is torn the knee may become unstable and give out. This typically occurs when a pivoting, cutting or side-stepping maneuver is attempted. Thus many people often have difficulty doing their job or playing sport.
When the knee gives way the other structures inside the knee may also be injured. The menisci (the shock absorbers) and articular cartilage (the cushioning cartilage) are damaged. Repeated giving way may lead to increasing pain, instability and locking. The more the knee gives out the more the knee is damaged. This can lead to osteoarthritis at an early age. Thus we recommend surgery in the young active patient
The ACL rarely heals thus we need to reconstruct this ligament from other tissue around your knee. The most commonly used grafts are the smallest hamstring tendons; or the middle third of your patella tendon. There is little difference between the two grafts. Each graft has it’s advantages and disadvantages so we use the graft that best suits you
The success of the operation is very dependent on you. A lot of hard work is required to get the knee as strong as possible before the operation and to rebuild the muscles and restore the knee motion after the operation. Your knee may not be normal following the surgery but if all goes well and you work hard it should be greatly improved from the painful unstable knee you currently have.
The operation is usually done as a daystay case ie you don’t stay in hospital. You go home that night. The operation is moderately painful however you are given strong painkillers to take home. You will go home with a cryocuff that keeps the knee cool and comfortable and crutches. You will then start an intensive rehabilitation program.
The knee will be swollen, sore, stiff and bruised for a number of weeks. You will be on crutches until you can walk normally. This takes about 7-10 days. Return to work is dependent on your job. An office worker is off for 1-3 weeks & manual labourer 6-12 weeks.
You will not be able to play cutting or pivoting sports for 9 months as it takes time for the graft to mature. Early return may result in failure. There is a greater than 90% chance your knee will be stable after the surgery and rehabilitation period if you look after it. If you don’t look after it the graft may rupture or stretch out. Other complications include infection and numbness around your scars. If you have a hamstring graft this comes from your inner thigh which maybe sore for up to 6 weeks. These grow back over a 1-2 year period. Sometimes this scar tissue can snap, feeling like a pulled hamstring. Don’t worry this will settle. With a patella tendon graft you can get pain in the front of the knee and if you fall you may fracture your kneecap
Very occasionally the screw to secure your graft backs out and requires removal.