Anterior cruciate ligament (ACL) injury

An anterior cruciate ligament (ACL) injury is a common knee injury in sport, whether you are an athlete or play sport socially, and even in work requiring high physical demands. This injury can occur due to sudden stops, changes in direction, or jumping/landing. An ACL injury can be a painful and generate a lot of swelling, which is a frustrating experience when trying to return to work daily life or sports.

The symptoms of an ACL injury can vary, but some of the most common include:

  1. A popping sound or sensation in the knee at the time of injury.
  2. Pain and swelling in the knee, which usually develops within a few hours of the injury.
  3. Difficulty trying to straighten or bend the knee.
  4. Feeling of instability or looseness in the knee joint when trying to weight bear.


Did you know that the ACL

  • Is one of 4 main ligaments of the knee.
  • Connects the tibia and the femur.
  • Prevents anterior translation of the tibia on the femur or posterior translation of the femur on the tibia.
  • Limits medial rotation of the femur on the tibia in closed-chain movement.
  • Provides stability to the knee joint:
    • Helps prevents tibia moving forward.
    • Helps prevents tibia rotating.
    • Helps prevent knee opening up sideways (varus/valgus)



The good news is, with comprehensive assessment, diagnosis and treatment, many people can return to their normal activities.

Having spent 10 years working in the Acute Knee Clinic Service and alongside Orthopaedic Consultants, we have the expertise to diagnose and support you get back to your desired activity with a bespoke plan that is right for you.


To diagnose an ACL injury, we will perform a physical exam of your knee, which may include moving your knee in various directions to test the knee stability and whether there is meniscus (cartilage) involvement. If an MRI is required, we have direct links with Orthopaedic Consultants to arrange an MRI privately, or we will write to your GP communicating the likely diagnosis and suggesting an MRI to confirm if appropriate.


This depends on your overall health and your overall level of activity you would like to return to. If for example the goal is to return to running, this does not involve quick change of direction, it’s very likely that non-surgical treatment may be recommended, such as physical therapy, to help strengthen the muscles around the knee and improve stability.

Surgery may be necessary to repair or reconstruct the ACL. If the knee continues to be unstable regardless of rehabilitation or if the client is returning to change of direction sport when there is a rupture of the ACL along with a meniscus injury. The surgery most frequently involves using part of the hamstring tendon to create a new ligament.


Recovery from an ACL injury can take many months involving physical therapy to regain strength, range of motion, and co-ordination, which all help to provide stability to the knee. The recovery following surgery in most cases is likely to be 12 months for return to change of direction sport.


While not all ACL injuries can be prevented, there are steps you can take to reduce your risk of injury.

  1. Warming up properly before physical activity.
  2. Strength and conditioning exercises.
  3. Using proper techniques and form when jumping or pivoting during sports activities.

We can provide a comprehensive plan to address any strength deficits for injury prevention and teach you correct jumping techniques to reduce your risk of an ACL injury.

In conclusion, an ACL injury can be a painful and frustrating experience, but with proper treatment and care, many people can return to their normal activities. If you think you may have an ACL injury, book into our clinic and we will support you with your journey, whether its rehabilitation to prevent the need for surgery, prehabilitation to get you strong before surgery or rehabilitation following surgery.

rehab explained

Although every patient is different and there is a significant variety in when people achieve different milestones, here is a generalised guideline/timeframe for return to some key activities

rehab timetable