Many people experience new symptoms and change in function of their knee, and it is important to know this is normal and common after ACL reconstructive surgery. This page is designed to give you an overview of what to expect, and the best evidence based management of your knee now and into the future.
Up to one third of people may experience symptoms, poor function or quality of life in the early years following their injury(1). The timing of onset and severity of symptoms varies, and it is poorly understood which individuals may experience symptoms. It is likely a large variety of factors (i.e. age, other injuries at the time of or after initial injury, being overweight, muscle strength, physical activity levels) play a part.
Knee osteoarthritis (OA) is a common musculoskeletal condition with incidence increasing with age. It is characterised by the presence of cartilage thinning, bone spurs/cysts, and narrowing of space between the joint.
Isn’t osteoarthritis just a normal part of ageing?
Now that you have had an ACL injury and surgery your knee is at greater risk of osteoarthritis (OA) development at an earlier age
Does surgery reduce my risk of osteoarthritis?
No, it restores the stability of the knee joint but it does not reduce the risk of OA.
Does running or playing impact sports after ACL injury increase my risk of osteoarthritis?
No, there is no evidence to suggest this relationship. Remaining physically active with your normal activities, within your functional capabilities is the most important consideration.
Do I need to be worried about the risk of osteoarthritis? 
No, osteoarthritis is not always associated with symptoms. I.e. 50% of people over age 75 have knee osteoarthritis on X-ray, however only 25% have knee symptoms.
However, further research into osteoarthritis following ACL injury is required to determine this relationship.
There is good research to suggest the symptoms and functional impairments associated with knee osteoarthritis can be improved and controlled by exercise therapy and education (3). These are the top 2 recommendations by the American Academy of Orthopaedic Surgeons Treatment of Knee Osteoarthritis Guidelines (3)
1.Exercise therapy should include stren
gth training, balance training, and cardiovascular activity (i.e. walking, running, bike riding). These can be performed independently once prescribed by an appropriate health professional
2. Education regarding weight loss +/- referral to dietician from GP. Weight loss can improve symptoms and function (4). Note, this relationship is not proven specifically in people following ACL injury. 
However, healthy diet and weight are beneficial for many other chronic health conditions and should always be a priority.
3. In combination with the above, a individualised medication regime (i.e. non steroidal anti-inflammatory drugs/NSAIDS)prescribed by your GP may be useful.
There is currently inconclusive evidence for the use of other modalities such as intra-articular injections, braces, massage and acupuncture.
- Graded exercises and return to activity following injury is important to ensure the knee joint is gradually loaded.
- Progression should be based on achieving strength/functional goals not a time point
- Continue seeing a health care professional (i.e. exercise physiologist or physiotherapist) until all strength and functional deficits are restored.
- Continue resistance training even when returned to sporting activities and even if you didn’t do it before
- Maintain healthy diet and weight
- Wasserstein, D., et al. (2015). “KOOS pain as a marker for significant knee pain two and six years after primary ACL reconstruction: a Multicenter Orthopaedic Outcomes Network (MOON) prospective longitudinal cohort study.” Osteoarthritis Cartilage 23(10): 1674-1684.
- Brown, G. A. (2013). “AAOS clinical practice guideline: treatment of osteoarthritis of the knee: evidence-based guideline, 2nd edition.” J Am Acad Orthop Surg 21(9): 577-579.