The ACL (Anterior Cruciate Ligament) sits in the middle of the knee linking the tibia (shin bone) to the femur (thigh bone) and is important in controlling movement of the two bones, particularly during twisting pivoting sports and dancing.
Anterior cruciate ligament (ACL) reconstruction surgery is an arthroscopic (keyhole) surgical procedure. The same two small incisions as for arthroscopy are used at the front of the knee, with another small incision above the knee, and a 3-5cm incision at the front of the knee to obtain the graft and feed it into the knee. By operating with this technique we can perform this surgery as day case surgery under a general anaesthetic with a more rapid return to normal daily activities.
Anterior Cruciate Ligament Graft
The procedure involves excising the damaged ACL and replacing it with a graft of your own tissues. We recommend using a hamstring graft. In this technique tendons from the inside of your knee are removed via a 3-5cm incision just below the knee and used to reconstruct your ACL. Despite the loss of these tendons you are unlikely to notice a significant reduction in the strength of your hamstrings.The graft is threaded across the knee via 2 drill holes. The first drill hole enters the knee where the ACL attaches to the tibia and the second is across the knee in the femur, where the ACL is also attached. Both of these drill holes are made through the small incision used to remove the hamstring tendons as the entry point is at the hamstring insertion on the tibia. The graft is pulled through the knee and fixed in place using special devices and screws.
After ACL Reconstruction
Most ACL reconstructions are performed as a day case, but if the surgery is later in the day or if you live alone you may need to spend the night. The knee is filled with local anaesthetic at the end of the operation to numb the pain. You will be mobilised by a physiotherapist using crutches and given some exercises to perform. Your physiotherapy rehabilitation will start a week after surgery and is split into different phases. In the first 3 months you will regain a full range of movement mainly performing ‘closed chain exercises’. These are exercises with your foot on the floor or a pedal of a stationary bike that do not over stress the healing graft. After 3 months the graft has healed strongly to the bone in the tunnels either side of the knee joint and your rehabilitation can progress. Between 3 and 6 months you start ‘open chain exercises’ such as jogging in a straight line and progress to shuttle runs in the gym. You will also do ‘proprioception’ exercises to train the muscles to respond quickly. Between 6 and 9 months you can start sport specific training. If you want to play football you can return to training but should avoid tackling and competitive games. You can return to gentler sports such as tennis at this time.Finally, at 9 months your rehabilitation is complete and you can return to your chosen sport although it is often sensible to avoid full competitive contact until one-year post surgery.
Success of ACL reconstruction
Most patients should be able to get back to their chosen sport after an ACL reconstruction. However, some avoid it due to the risk of further injury to either or the same knee. The risk of ACL graft rupture is an approximately 6%, but this is also the risk of rupture of the normal ACL in the other knee.