Arthritis in Humans


A chronic degenerative disease due to gradual progressive damage to the joint characterized by:

  • Loss of cartilage
  • Joint dysfunction
  • Inflammation
  • Pain
  • Disability
  • Calcification of the cartilage

With progression, joints appear swollen, become stiff and are extremely painful.

Osteoarthritis, or degenerative joint disease, is the most common form of arthritis.

Healthy Knee Joint

Arthritic Knee Joint


Arthritis is caused by mechanical stress with insufficient self-repair resulting from:

  • Misalignment of bones
  • Excess weight
  • Loss of muscle supporting joints
  • Repetitive strain from daily activities (work or sport)
  • Joint injury
  • Breakdown of the synovial fluid in the joint
  • Potentially hereditary
  • Potential metabolic link to body fat
  • Possibly sex hormones play a role

Osteoarthritis has a relationship with, but is not caused by aging

Cause Mechanisms

As a person ages, the water content of the cartilage decreases as a result of reduced cartilage tissue components (aggrecan, chondroitin sulphate and hyaluronic acid) reducing the cartilage's resilience.

With the loss of proteoglycans (aggrecan is an important component) the collagen fibers in the cartilage become susceptible to degeneration.

Degeneration and breakdown of cartilage leads to inflammation in the joint which is aggravated by activity and leads to the development of pain.

New bone growths called ‘spurs’ or osteophytes can form in the margins of the joints which are:

  • Painful
  • Debilitating


Osteoarthritis can occur in all synovial joints that allow movement.

The most common areas for osteoarthritis are:

  • Knees
  • Hips
  • Hands
  • Spine


Cartilage Structural Changes

Osteoarthritis results in progressive cartilage degradation characterized by the softening and erosion of the cartilage surface.

Breakdown of cartilage components (proteoglycans – aggrecan) leads to a decrease in the compressive stiffness of the cartilage that in turn accelerates the rate of collagen loss in the cartilage.

Osteophyte (bone spurs) formation, bone remodelling and synovial membrane inflammation occur, resulting in further tissue degradation.

In the early phase of osteoarthritis, destructive enzymes are expressed due to repeated mechanical activity which enhances cartilage breakdown.

Osteoarthritis induced cartilage damage follows multiple cell destructive cascades that once activated result in irreversible damage to the tissue. 


Non-Surgical Treatments

There is no cure for osteoarthritis. A combination of treatment options to control the symptoms are:

  • Medications – acetaminophen and NSAID’s
  • Resting the joint
  • Losing weight, if necessary (slows down progression)
  • Physical therapy, including walking and swimming, to increase joint mobility
  • Braces for alignment
  • HA injections into the joint or supplementation
  • Steroid injections

Surgical Treatments

Surgical procedures include:

  • Joint resurfacing
  • Surgery to remove loose cartilage, bone spurs or loose bone
  • Osteotomy or bone removal to realign deformed joints
  • Joint replacement