Why is Osteoarthritis Painful?

Osteoarthritis is painful because it involves the gradual breakdown of cartilage in the joints, leading to:

Cartilage Loss – Cartilage acts as a cushion between bones. As it wears down, bones start rubbing against each other, causing pain and stiffness.

Inflammation – The body responds to joint damage by releasing inflammatory chemicals, leading to swelling and pain.

Bone Spurs – As cartilage deteriorates, bones may grow extra bony projections (osteophytes), which can press on nerves and tissues, increasing pain.

Joint Fluid Changes – The synovial fluid, which lubricates joints, can become less effective, reducing shock absorption and making movements more painful.

Muscle Weakness & Stiffness – OA can cause muscles around the joint to weaken, leading to instability and discomfort.

How Does Exercise Help?

  • Strengthens Supporting Muscles

    The knee joint relies on surrounding muscles. Primarily the quadriceps, hamstrings, glutes, and calf muscles to provide stability and support. When these muscles are weak, the knee joint takes on more stress, accelerating cartilage breakdown. Strengthening these muscles helps:

    • Reduce direct pressure on the joint
    • Improve knee alignment and stability
    • Prevent excessive strain on the ligaments and tendons

  • Reduced Pain and Stiffness

    Knee OA causes pain and stiffness due to joint inflammation, cartilage degeneration, and reduced joint lubrication. Exercise helps by:

    • Increasing blood flow: This delivers oxygen and nutrients to the joint, aiding in repair.
    • Stimulating synovial fluid production: This natural lubrication reduces joint stiffness.
    • Releasing endorphins: These natural painkillers can help reduce discomfort.

  • Improves Joint Stability

    Knee instability can make it difficult to walk, climb stairs, or perform daily tasks. Strengthening exercises improve neuromuscular control, ensuring that the muscles around the knee work together to keep the joint stable. This helps:

    • Prevent buckling or giving way of the knee
    • Reduce the risk of falls and injuries
    • Improve confidence in movement

  • Enhances Mobility and Function

    Many people with knee OA experience difficulty with movements like standing, walking, and bending. Exercises help improve muscle endurance and coordination, making everyday tasks easier and less painful.

  • Slows the Progression of Osteoarthritis

    While OA is a progressive condition, studies suggest that regular strength training can slow cartilage degeneration and preserve joint function. This is because:

    • Stronger muscles absorb impact forces, reducing stress on cartilage.
    • Improved joint alignment decreases uneven wear on the joint.
    • Better circulation promotes cartilage repair and reduces inflammation.

    By strengthening the knee-supporting muscles, individuals can delay the need for invasive treatments like surgery.

  • Reduces Load on the Knee Joint

    Every extra pound of body weight puts approximately 4 pounds of additional pressure on the knee joint. Exercise helps with weight management by:

    • Building muscle mass, which increases calorie burn.
    • Enhancing metabolism, aiding in weight control.
    • Improving movement efficiency, so less effort is required for daily activities.