Osteoarthritis and physical activity
What is osteoarthritis?
Osteoarthritis (OA) encompasses a spectrum of mechanical abnormalities that can be best described as degeneration or degradation of joints, without inflammation, which can generate symptoms such as pain, tenderness, stiffness and locking. Over time and due to a variety of factors, the space within the joint narrows and loss of the protective cartilage ensues, causing further damage to surrounding muscles and ligaments. The pathogenesis of OA is unclear, but is attributed to an improper loading of the joint. In younger patients, osteoarthritis is often a secondary result of injury to the joint. . In seniors, osteoarthritis is the most common cause of physical inactivity . General risk factors include age, genetics, and gender. Joint overload, muscle weakness, and being overweight are additional contributing factors . In the early stages of the disease, treatment is generally conservative, and involves modified activity and rest.
What are the effects of physical activity on osteoarthritis?
Physical activity that incorporates moderate joint loading is beneficial in both prevention and treatment of OA . Joint stability is increased with physical activity due to improvements in muscle strength and neuromuscular function. Careful physical training can also improve joint cartilage degeneration . In patients with OA, aerobic exercise reduces pain via increased endorphin levels in the brain, and is associated with weight loss, which can reduce total load on the joint. Running in particular, through its association with lower body mass index (BMI) reduces OA and hip replacement risk , although in advanced cases of OA it may cause an increase in pain and physical activity should be modified. Generally speaking, dynamic strength training beginning with body weight is advised. Type of physical activity is also based on the joint in question. For knee OA, strength training of the quadriceps and gluteus muscles may be key, while hip flexibility is also important .
What are the risks?
The most obvious risk to the patient is further injury to the joint, as this is often associated with physical activity. Careful selection of suitable physical activities (i.e. avoidance of contact sports such as football) will decrease the chance of injury. In addition, sports involving high loading forces (axial compression and twisting) or repetitive shocks can increase risk of OA . These include sports such as basketball, football, rugby and waterskiing, among others. In severe cases of patellofemoral OA, even walking up and especially downhill can increase pain, in which case Nordic walking sticks are recommended to unload the knee.
- Roos E. Osteoarthritis, in Physical activity in the prevention and treatment of disease, Professional associations for physical activity (Sweden), Editor. 2010, Swedish National Institute of Public Health: Stockholm. 498-509.
- Hootman JM, Fitzgerald SJ, Macera CA, Blair SN. Lower extremity muscle strength and risk of self-reported hip or knee osteoarthritis. J Phys Act Health 2004;1(4):321.
- Manninen P, Riihimaki H, Heliovaara M, Suomalainen O. Physical exercise and risk of severe knee osteoarthritis requiring arthroplasty. Rheumatology (Oxford) 2001;40(4):432-7.
- Roos EM, Dahlberg L. Positive effects of moderate exercise on glycosaminoglycan content in knee cartilage: a four-month, randomized, controlled trial in patients at risk of osteoarthritis. Arthritis Rheum 2005;52(11):3507-14. Available at: http://dx.doi.org/10.1002/art.21415.
- Williams PT. Effects of running and walking on osteoarthritis and hip replacement risk. Med Sci Sports Exerc 2013;45(7):1292-7. Available at: http://dx.doi.org/10.1249/MSS.0b013e3182885f26.
- Bennell KL, Hinman RS. A review of the clinical evidence for exercise in osteoarthritis of the hip and knee. J Sci Med Sport 2011;14(1):4-9. Available at: http://dx.doi.org/10.1016/j.jsams.2010.08.002.
Authors & expert
Expert: Romain Seil3.
1 Centre Hospitalier Universitaire Vaudois, Policlinique Médicale Universitaire, CH-1011 Lausanne, Switzerland
2 Luxembourg Institute of Health, Sports Medicine Research Laboratory, L-1460 Luxembourg, Luxembourg
3 Centre Hospitalier de Luxembourg - Clinique d'Eich, Département de l'Appareil Locomoteur, L-1460 Luxembourg, Luxembourg