Anterior Cruciate Ligament Reconstruction

Anterior_1ACL reconstruction can improve the stability and the function of your knee following an injury. The ACL is a strong ligament that runs diagonally through the middle of your knee. It helps to keep your knee stable, especially when you turn, or when your knee joint moves from side to side. The ACL is one of the most commonly injured ligaments. It's usually torn when you slow down very quickly while turning or sidestepping at the same time. You’re more likely to injure your ACL if you play sport, particularly basketball, volleyball, rugby or football, or if you ski.   ACL reconstruction involves replacing your torn ligament with a graft. The graft is usually taken from a tendon in another part of your knee, for example, your hamstring or patella tendon. ACL reconstruction is carried out to try to make your knee stable. This means that you may be able to return to playing sport. However, it will depend on whether there are other problems with your knee, such as torn cartilages, other ligament injuries or arthritis.  

Preparing for an anterior cruciate ligament reconstruction

You will usually have ACL reconstruction three to eight weeks after your injury. This allows any swelling to go down. Your surgeon may ask you to have physiotherapy during the weeks after your injury. This is to make sure you can move your knee as fully as possible before your operation. Your surgeon will explain how to prepare for your operation. For example, if you smoke, you will be asked to stop. This is because smoking increases your risk of getting a chest and wound infection, which can slow your recovery. ACL reconstruction can be done using either local or general anaesthesia. A local anaesthetic completely blocks pain from your knee area and you will stay awake during the operation. If you have a general anaesthetic, it means you will be asleep during your operation. You will usually be asked to not eat or drink for about six hours beforehand. Your surgeon will have a chat with you about your procedure and any pain you might have. Take this time to ask any questions you’d like answered so you understand what will happen. It can be helpful to prepare some questions beforehand. You may also be asked to give your consent for the procedure to go ahead by signing a consent form.  

What happens during an anterior cruciate ligament reconstruction?

Your surgeon will examine your knee to check how badly your ligament is torn and if any other tendons or ligaments have been damaged. Your surgeon will make a number of small cuts in the skin over your knee that is being treated. These cuts are called portals. He or she will insert an arthroscope and otherAnterior_2 surgical instruments into your knee through these cuts. An arthroscope has a thin, flexible tube with a light and camera on the end of it. This allows your surgeon to see inside your knee. Your surgeon will remove the piece of tendon that will be used as the graft. He or she will usually take the graft from your patella tendon, which connects your kneecap and shin-bone or from one of your hamstring tendons at the back of your knee.   Your surgeon will drill a tunnel through your upper shin bone and lower thigh bone. He or she will put the graft into the tunnel, attach it to your bones and fix it in place, usually with screws. These are normally left inside your knee permanently. Your surgeon will close the cuts with stitches or adhesive strips. Your operation will usually last between one and a half and two hours.  


You will wake up in recovery with the knee bandaged. You will be given pain medications if required. It is safe to move the knee, but you will be encouraged when resting to keep the knee straight. It is safe to fully weight bear through the knee straight away, but often it is more comfortable to start walking with some elbow crutches. Most patients will only use these for the first few days. By one to two weeks you should be walking normally. It is normally safe to drive when you are walking normally and putting all your weight through the leg (you can perform an emergency stop). Please check with your insurance company that you are covered before starting to drive again. The knee will have a tendency to swell in the first six weeks. It is important to ice the knee between exercises and when resting to keep it elevated. You will be given some exercises to help rehabilitate the knee. The rehabilitation is split into three phases: PREHABILITATION / REHABILITATION Pre-operative exercises Before the operation, it is important that you have as near to full pain-free movement as possible. Ideally, a few weeks before the surgery you should start exercises building up your quadriceps and hamstring strength. This trains the muscles up and makes it easier to get going after the surgery. Phase1. (0-1weeks following surgery) This phase involves regaining a full range of movement (especially full extension). It is important that these exercises are performed for short periods but regularly (rather than one longer period). It starts as soon as you recover from anaesthesia. You will be allowed to put full weight on your operated leg. You may or may not need a brace to support your leg. (depends upon your preoperative quadriceps and hamstring muscle strength) Calf exercises Move the foot up and down from the ankle to maintain good circulation as soon as you recover from anaesthesia. Calf exercises Extension exercises Sit on a firm surface and fully straighten your knee. To help the knee go straighter tighten the front thigh muscles (quadriceps). Pull your toes up towards your face and at the same time push your knee back into the floor. Hold for 10 seconds and repeat. Extension exercises Knee bends Slide your heel up and down a firm surface bending and straightening your knee. Knee bends Static hamstrings With the knee bent to about 20 degrees from fully straight push the heel into the floor and hold for 10 seconds. Static hamstrings  Phase 2 (1-8weeks following surgery) This phase is about improving muscle strength and continuing to improve movement back to full. It is important to perform these exercises regularly and we recommend at least twice a day. The more effort that is put into the rehabilitation the better the recovery and quicker the return to full activities. Straight leg raise Lie on your front. Lift the leg straight up in the air and lower. Try and stop the downward fall of the leg by “quickly” contracting your muscles. As you progress you can add weight to your ankle. Static hamstrings   Leg raise in-side lying Lie on your side with your operated leg uppermost. Lift and lower the leg using your outer thigh muscles. Leg raise in side lying Sit to Stand Slowly stand up from a chair. As you progress put the unoperated leg forward so more of the work is done by the operated leg. One leg balance Stand on the operated leg with it slightly bent. Try to balance for 30 seconds. As you progress try closing your eyes. Hamstring catches Stand on your un-operated leg. Bring your other heel to your bottom. Then lower your foot, try and stop the downward movement by “quickly” contracting your hamstring muscles. Rope Walk Place a skipping rope along the floor. Walk along it carefully keeping your balance Phase 3 (8-16 weeks following surgery) At this stage phase 2 exercises can be progressed at increased speed, weight and number of repetitions. You can now start building in some exercises to help proprioception (joint stability coordination).
  1. Skipping
  2. Step-ups and down
  3. Quadriceps stretch
  4. Jogging
  5. Cycling
  6. Swimming
  7. Gym work.
  8. Wobble board
  9. Single leg squats
Phase 4 (16 weeks following surgery) Rehabilitation can now be directed at graded return to sports. When jogging you can start to build in some direction changes initially running long curves, but as you progress making the direction changes more acute. At 6 months following surgery if the musculature is sufficient sport specific training exercises can be started. We would not recommend return to competitive sport until at least nine months following surgery. As with all operations if at any stage anything seems amiss it is better to call for advice rather than wait and worry. A fever, or redness or swelling around the line of the wound, an unexplained in- crease in pain should all be brought to the attention of your doctor.