What is Osteoarthritis?

What is Osteoarthritis?


By Dr. Anil Raheja, Orthopaedics

Osteoarthritis is a joint disease that mostly affects cartilage. Cartilage is the slippery tissue that covers the ends of bones in a joint. Healthy cartilage allows bones to glide over each other. It also helps absorb shock of movement. In osteoarthritis, the top layer of cartilage breaks down and wears away. This allows bones under the cartilage to rub together. The rubbing causes pain, swelling, and loss of motion of the joint. Over time, the joint may lose its normal shape. Also, bone spurs may grow on the edges of the joint. Bits of bone or cartilage can break off and float inside the joint space, which causes more pain and damage

What causes osteoarthritis?

The cause of osteoarthritis is unknown. Factors that might cause it include:

  1. Being overweight
  2. Getting older
  3. Joint injury
  4. Joints that are not properly formed
  5. A genetic defect in joint cartilage
  6. Stresses on the joints from certain jobs and playing sport

Osteoarthritis has as its main symptoms:

  • Pain – from moderate to severe
  • Problems moving affected joints.
  • Stiffness – more severe on waking up in the morning, and improves within 30 minutes when the individual starts moving about.

In some cases people with osteoarthritis may have no symptoms. Symptoms are usually only felt in either one joint, or a just a few at any one time. In many cases the symptoms come on slowly.

Other signs and symptoms may include:

  • Affected joints are larger than usual
  • After not moving the joint for a while pain and stiffness may worsen
  • Joints are warm
  • Loss of muscle bulk
  • Tenderness in the affected joint
  • The affected joints will have a limited range of movements
  • The patient may experience a grating or crackling sound/sensation in the affected joint.

Diagnostic & Tests-

A diagnosis of osteoarthritis may be suspected after a medical history and physical examination is done. Blood tests are usually not helpful in making a diagnosis. However, the following tests may help confirm it:

  1. Joint Aspiration. The doctor will numb the affected area and insert a needle into the joint to withdraw fluid. The fluid will be examined for evidence of crystals or joint deterioration. This test can help rule out other medical conditions or other forms of arthritis.
  2. X-ray. X-rays can show damage and other changes related to osteoarthritis to confirm the diagnosis.
  3. MRI. Magnetic resonance imaging (MRI) does not use radiation. It is more expensive than X-rays, but will provide a view that offers better images of cartilage and other structures to detect early abnormalities typical of osteoarthritis. If you wish to discuss about any specific problem, you can consult a orthopedist and ask a free question.