Written by Mark Robbins, Senior Physiotherapist APPI Clinics
What is Osteoarthritis?
Osteoarthritis (OA) has been previously explained as simple “wear and tear” or an inevitable part of ageing which leads to joint damage and cartilage breakdown. However, with newer scientific research it shows this in a very different picture. OA is now understood as a whole-joint condition, involving not just the cartilage but bone, synovium, ligaments and surrounding tissues (OARSI, 2019). Normalised findings are thickening of bone lining, bony growths (osteophytes), joint capsule thickening and synovial fluid changes.
Rather than seeing OA as being destructive, these changes represent the body’s attempt to adapt and stabilise the joint in response to altered load (Hunter& Bierma-Zeinstra, 2019). OA isn’t about your joint falling apart, it’s your joint trying to protect itself.
Why loading the joint matters
One helpful way to understand why loading the joint matters is to imagine the joint like a sponge. As we compress a sponge, through weight bearing activities for example a squat, fluid is squeezed out and then reabsorbs fresh fluid in. This fluid is crucial as this carries all the nutrition for our joint to remain healthy (Mobasheri et al., 2019). Therefore, a reason why osteoarthritis is becoming more prevalent within weight bearing joints is because people are not loading their joints enough which leads to deconditioning and poor joint health (Briggs et al., 2018). Think of it like WD-40 for your joints.
Alongside good joint health, when we load our joint, it also helps strengthen muscles. Think of muscles like shock absorbers, if they are not absorbing any force this can go directly towards the joints which can lead to them becoming grumpy.
Why weight matters
As we get older, it’s normal for our weight to change, shifts in metabolism, activity levels, or even medication can all play a role. There’s no single “perfect” weight for everyone. What matters most is finding a balance that supports your joints and overall health.
Weight influences osteoarthritis in two main ways:
1) Systemic Inflammation
Body fat isn’t just storage it releases inflammatory chemicals, known as adipokines, into the bloodstream. These can increase how sensitive our joints feel, even in places that don’t carry weight, such as the hands. This systemic inflammation can contribute to flare-ups and ongoing discomfort (Griffin & Guilak, 2008; Francisco et al., 2018).
2) Load on our joints
Extra body weight increases the force going through weight-bearing joints. Research shows that for every 1 kg of weight gained, around 4 kg of force is added through the knees with each step (Messier et al., 2005). In fact, gaining 5 kg can raise the risk of knee or hip OA by around 35% (Coggon et al., 2001).
The focus isn’t on achieving a specific number on the scales but it’s about making small, sustainable lifestyle changes that reduce stress on your joints, improve function and support long- term health.
Why Imaging is not the best tool for diagnosing Osteoarthritis
Structure does not equal symptoms.
Scans take a picture of a joint which only shows structure but not pain. Many people have ‘OA changes’ on scans but have no pain at all, while others can experience significant symptoms but may only show mild changes on imaging (Englund et al., 2008; Bedson & Croft, 2008). Pain is our bodies protective mechanism and can be influenced by so many factors including, inflammation, load tolerance, lifestyle, general health and nervous system sensitivity, none of which can be seen on an X-ray.
Secondly scans do not predict function.
Imaging cannot tell how well someone is functioning for example their muscle strength, how the joint responds to load, how active they are. Function is a far better indicator to how someone is coping (NICE OA Guidelines, 2022).
Negative labelling can harm rehabilitation.
When we have a scan, professional practitioners will describe what they see on an image. However, these words can be very damaging. The language used to describe OA has a powerful effect on how someone understands and manages their condition. Words like “your knee is worn out”, “bone on bone”, “wear and tear” can sound alarming and often lead people to believe their joint is fragile or damaged beyond repair. As result these fear-based messages can increase worry, reduce confidence and make people avoid using or loading their joint (Bunzil et al., 2017). This cycle reinforces the belief that the joint is ‘damaged’ even though the body is simply responding to reduced activity. Therefore, diagnosing OA should be done through a thorough assessment which looks at a detailed history of their symptoms and general health. Ruling out other causes of pain, seeing how the joint behaves with load through it and monitor to see how function may change over time. Therefore, imaging is helpful to rule out other conditions but it should never be the standalone tool to diagnose or guide OA treatment.
Summary
Osteoarthritis is no longer viewed as a “wear-and-tear” problem it’s a condition of change and adaptation. Your body is aiming to protect and stabilise your joints, not damage them. The most effective way to support this process is through regular exercise or loading, building muscle strength, managing pain and flare-ups, improving your overall health and focusing on how the joint functions rather than what a scan looks like.
Your joints are made to move.
At APPI Clinics, we’re passionate about helping people with osteoarthritis stay active, informed, and confident. If you’d like tailored guidance, a review of your symptoms, or support in building a plan that feels right for you, one of our physiotherapists will be happy to see you. You’re always welcome to reach out or pop in; we also offer a free 15-minute phone call with one of our physiotherapists.
From January, we’re excited to be introducing an OA and OP mat Pilates and strength class with our senior physiotherapist Sneha Kamat, designed to help you build confidence, strength, and mobility in a supportive group setting. We’d love to welcome you and be a part of your active lifestyle!
Reference List
Bunzli, S., Smith, A., Schütze, R., Lin, I. & O’Sullivan, P. (2017) ‘Beliefs underlying pain-related
fear and how they evolve: A qualitative investigation of people with knee osteoarthritis’, BMJ
Open, 7(5), e016195.
Coggon, D., Croft, P., Kellingray, S., Barrett, D., McLaren, M. & Cooper, C. (2001) ‘Knee
osteoarthritis and obesity’, International Journal of Obesity, 25, pp. 622–627.
Englund, M., Guermazi, A., Gale, D., Hunter, D.J., Aliabadi, P., Clancy, M. & Felson, D.T. (2008)
‘Incidental findings on knee MRI in middle-aged and elderly persons’, New England Journal of
Medicine, 359(11), pp. 1108–1115.
Francisco, V., Perez, T., Romero, A. et al. (2018) ‘Adipokines in osteoarthritis: pathogenic role and
potential therapeutic implications’, Frontiers in Physiology, 9, p. 794.
Griffin, T.M. & Guilak, F. (2008) ‘The role of mechanical loading in the onset and progression of
osteoarthritis’, Exercise and Sport Sciences Reviews, 36(4), pp. 195–202.
Hunter, D.J. & Bierma-Zeinstra, S.M.A. (2019) ‘Osteoarthritis’, The Lancet, 393(10182), pp. 1745–
1759.
Messier, S.P., Gutekunst, D.J., Davis, C. & DeVita, P. (2005) ‘Weight loss reduces knee-joint loads
in overweight and obese older adults with knee osteoarthritis’, Arthritis & Rheumatism, 52(7), pp.
2026–2032.
Mobasheri, A., Saarakkala, S., Finnilä, M.A.J., Karsdal, M., Bay-Jensen, A.C. & van Spil, W.E.
(2019) ‘Recent advances in understanding the pathophysiology of osteoarthritis’, F1000Research, 8,
F1000 Faculty Rev 2091.
National Institute for Health and Care Excellence (NICE) (2022) Osteoarthritis in over 16s:
diagnosis and management (NG226). London: NICE.
Osteoarthritis Research Society International (OARSI) (2019) OARSI guidelines for the non-
surgical management of knee osteoarthritis. OARSI.