A lot of people experience 'knee pain' at some point in their lives. Whether that's from years of high load sports or skipping the stairs at work, sore knees can stem from a multitude of factors. In particular, the knee is the most affected joint for osteoarthritis (OA) causing progressive wear and tear and potentially requiring a joint replacement.
How does knee OA cause pain?
Knee OA is a degenerative joint disease, causing progressive loss of the articular cartilage between the bones in the knee. The knee is a joint consisting of two articulations (connecting surfaces of bones). The primary joint surface of the knee is the tibiofemoral joint, joining the tibia (thigh bone) to the femur (shin bone). The secondary joint surface is the patellofemoral joint, joining the tibia to the patella (kneecap). Between these surfaces is cartilage that is disrupted through the process of OA. As this cartilage is poorly supplied by the blood, it does not recover so there is less cushioning between your bones where they may rub on each other during movements. This causes inflammation at the joint and changes the surfaces which may cause pain during certain movements as it is bone rubbing on bone.
How can a knee brace help me?
If you're reading this, you may be considering purchasing a knee brace to support the joint. This is true to a certain extent. However, it is important to consider the first line of treatment for knee OA is conservative, focusing on education (activity modification, weight loss) and physiotherapy exercise. These factors have been shown by the latest research to help reduce the load on the knee by minimising provocative movements but also through strengthening supporting muscles around the knee and at other joints (hip and ankle) to offload the knee which indirectly 'supports' the joint. Nonetheless, it can take a few weeks to start implementing these changes and seeing strength gains in your muscles to address your symptoms. Therefore, a knee brace can help provide temporary relief in conjunction with a reviewed physiotherapy program. Here are some indications that you may benefit from a knee brace:
GP, physiotherapist, orthotist recommends it
unable to modify activities (long standing hours at work)
high activity levels and loading through knee joint
feelings of giving way
anxious when performing exercises.
So which knee brace should I buy?
The number of knee braces on the market is overwhelming, with many promising to reduce pain instantly or leaving you looking like you have a cyborg leg. Therefore, it is important to understand what makes a knee brace effective specifically for knee OA to maximise effectiveness and minimise discomfort. To differentiate, these are the four main knee braces:
1. Unloader brace
These are specifically designed for knee OA, as they 'distract' or 'unload' the joint with the diagonal straps, increasing the joint space within your knee. These help with shifting the weight bearing force on the knee which is helpful if you predominantly have degeneration on one side. The brace applies a force limiting your knee adduction moment (knees caving in) as the 3-point mechanism applies counterforce to distribute load and correct alignment. This is an evidence-based brace with studies demonstrating patients having reduced pain, reduced medication usage and an increase in quality of life. This has been examined quantitatively with studies showing measurable increases in the joint space despite the cartilage loss.
2. Knee sleeve
These look like sport neoprene sleeves, with studies showing that this brace provides light compression on the skin and sensory awareness which may improve confidence but structurally does not add as much as the unloader. However, this brace may be helpful in terms of maximising comfort and allowing movement if your symptoms aren’t severe and wish to remain active.
3. Patellofemoral sleeve This sleeve is specifically for the patella (kneecap) instability as evident with the circular straps around the area. However, it does not target the joint surfaces deeper for the patellofemoral joint but may be helpful if your OA is localised at the patellofemoral joint preventing excessive movement of the kneecap.
4. Functional hinged brace
This brace looks very heavy duty and provides mechanical stability, but it's very bulky. The hinges allow you to lock your knee to certain ranges, but it may not be indicated by your physiotherapist. This is due to treatment for OA requiring you to maintain movement in your joint to perform exercises. These may be indicated if one aspect of your knee range of motion is very painful where restricting that portion may be advantageous to prevent further degeneration.
What else should I look out for?
As some of these braces can get very expensive, it is important to consult with your physiotherapist as to what is an appropriate brace for you as more expensive does not necessarily mean better. No design is necessarily better than the other but may be more suitable to certain individuals depending on their symptoms and progression of OA. An off-the-shelf model may also not be suitable for your knee compared to a custom-fit by an orthotist. It is also important to consider that knee braces will not slow your OA progression, but it will improve your ability to participate in rehab exercises, where while your muscles get stronger, you will be able to wean off wearing the knee brace.
If you have any questions about knee braces or knee OA, feel free to get in touch with us!
References
Alfatafta, H, Alfatafta, M, Alqaroot, B, Khanfar, A, Csernák, G, Boncz, I, & Molics, B. (2020). PMS73 EFFECTIVENESS OF USING THE UNLOADER - ONE KNEE BRACE ON THE PHYSICAL ACTIVITY AMONG PERSONS WITH MEDIAL KNEE OSTEOARTHRITIS (OA). Value in Health, 23, S228.
Briggs, Karen K, Matheny, Lauren M, & Steadman, J. Richard. (2012). Improvement in Quality of Life with Use of an Unloader Knee Brace in Active Patients with OA: A Prospective Cohort Study. The Journal of Knee Surgery, 25(5), 417-422.
Dessinger, Garett M, LaCour, Michael T, Dennis, Douglas A, Kleeman-Forsthuber, Lindsay T, & Komistek, Richard D. (2021). Can an OA Knee Brace Effectively Offload the Medial Condyle? An In Vivo Fluoroscopic Study. The Journal of Arthroplasty, 36(4), 1455-1461.
Gohal, Chetan, Shanmugaraj, Ajaykumar, Tate, Patrick, Horner, Nolan S, Bedi, Asheesh, Adili, Anthony, & Khan, Moin. (2018). Effectiveness of Valgus Offloading Knee Braces in the Treatment of Medial Compartment Knee Osteoarthritis: A Systematic Review. Sports Health, 10(6), 500-514.
Lee, Paul YF, Winfield, Thomas G, Harris, Shaun RS, Storey, Emerald, & Chandratreya, Amit. (2017). Unloading knee brace is a cost-effective method to bridge and delay surgery in unicompartmental knee arthritis. BMJ Open Sport & Exercise Medicine, 2(1), E000195.
Parween, Rizuwana, Shriram, Duraisamy, Mohan, Rajesh Elara, Lee, Yee Han Dave, & Subburaj, Karupppasamy. (2019). Methods for evaluating effects of unloader knee braces on joint health: A review. Biomedical Engineering Letters, 9(2), 153-168.
Yu, Shirley P, Williams, Matthew, Eyles, Jillian P, Chen, Jian Sheng, Makovey, Joanna, & Hunter, David J. (2016). Effectiveness of knee bracing in osteoarthritis: Pragmatic trial in a multidisciplinary clinic. International Journal of Rheumatic Diseases, 19(3), 279-286.