Knee Osteoarthritis (OA)

  • Knee OA is one of the most common causes of disability in the aging population and can have an effect on quality of life affecting physical and psychological parameters. 

  • Most common form of arthritis 

  • Affects more than 250 million people world wide (27 million in US) 

  • The Knee is the largest synovial joint in the human body

    • Due to the high use and stress of this joint - frequent site for painful conditions 

  • 2 types of arthritis

    • Primary - non-traumatic

    • Secondary- due to trauma or mechanical misalignment 

  • Knee OA signs/symptoms:

    • Pain

    • Stiffness

    • Crepitus (popping)

    • Tenderness

    • Swelling

  • This may be caused by the cartilage at the end of your bones wearing down, trauma, inflammation, biochemical reactions and metabolic derangements 

  • Risks of Knee OA

    • Repetitive Overuse without allowing for healing

    • History of knee injuries

    • Age: typically > 50, most often >65 years old 

    • Other conditions such as rheumatoid arthritis or gout

    • Family history/genetics 

    • Obesity

    • Stress 

    • Females > Males 

    • Weakness and joint laxity 

  • Management of OA is to control the painful signals originated from the joints but also to improve functionality and quality of life. 

  • Non-pharmacological therapies should always be attempted as the first line of treatment for knee OA

  • The absence of mechanics stimulation (movement) induces a more rapid cartilage degeneration due to cartilage softening/thinning and impaired joint mechanics and flexibility 

  • Light to moderate physical activity provides so many benefits besides mechanical and functional improvements → reduction of diabetes, cardiovascular events, falls, disability and improvement in mood and self efficacy 

  • Treatment

    • Cycling

    • Walking

    • Climbing stairs 

    • Isometrics

    • concentric/eccentric strengthening

    • Balance and stability 

    • Stretching 

    • Aquatics is also great starting point before land therapy - bridge the gap if fearful of movement 

    • Weight management 

  • Fun fact:: during walking the knee joint has to support 3-5 time the body weight - small changes in weight can change the forces on the joint

  • 10% risk reduction of knee OA per Kg of body weight decreased 

Reference: Mora JC, Przkora R, Cruz-Almeida Y. Knee osteoarthritis: pathophysiology and current treatment modalities. J Pain Res. 2018 Oct 5;11:2189-2196. doi: 10.2147/JPR.S154002. PMID: 30323653; PMCID: PMC6179584.