Osteoarthritis

What is Osteoarthritis?

Osteoarthritis is the most common type of non-inflammatory joint disorder. It begins with primary changes in the joint surfaces (articular cartilage) from hereditary factors and aging or secondary to damage from injury. Osteoarthritis (OA) can be localized to one or two joints, or involve multiple joints. The disease is not systemic, unlike rheumatoid arthritis and other diseases that involve the joints.

Osteoarthritis begins with painless changes in the articular cartilage and the joint lining (synovium). The cartilage starts to erode with particles irritating the synovium, causing stiffness, and swelling of the joint. When the underlying bone (subchondral bone) is eventually exposed by complete loss of the articular cartilage, exposed nerve endings cause significant pain. Changes of the bone from direct pressure and friction may lead to a need for corrective surgery. The most commonly affected joints are the fingers, hips, knees, and spine. Weight bearing joints, primarily the hips and knees, are especially vulnerable to osteoarthritis from obesity or secondary degenerative changes from injury. In the younger population (under 45), osteoarthritis is more prevalent in men, probably resulting from more injuries in the younger male population.

How is it diagnosed?

History: Individuals will relate morning stiffness that lasts less than 30 minutes. They have painful, stiff, and swollen joints aggravated by activity and relieved with rest. The pain worsens with increased activity and weight bearing throughout the day. There may be complaints of intermittent catching, grinding sensations, and decreased mobility of the joint.

Physical exam reveals swollen joints from increased synovial fluid and bone overgrowth, which may be warm to the touch. Heberden's or Bouchard's nodes may be palpated and seen on the fingers. Joint lines may be distorted with spurs and the area is often painful to the touch. Crepitus and pain with decreased range-of-motion (ROM) with both active and passive motion are noted. As the disease progresses, deformity and contractures may develop.

Tests: The diagnosis is confirmed with x-ray findings of decreased joint space, spurs or osteophytes, increased density or sclerosis of the subchondral bone and subchondral cysts.

There are no blood tests to confirm the diagnosis of osteoarthritis, but many tests will be ordered to rule out other causes of the symptoms and x-ray findings. These include a complete blood count (CBC), rheumatoid panel, and urinalysis. The joint fluid may be aspirated and examined to rule out infection, rheumatoid arthritis, and gout. Cartilage debris may be detected, but all other findings should be normal.

How is Osteoarthritis treated?

The main objectives are pain relief and slowing the progression of the disease. There are no medications for the direct treatment of osteoarthritis. Aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used to control these symptoms.

Education can help with understanding the importance of weight control and the effects of activity on the joints in relieving the symptoms and slowing the degenerative process. The use of supportive braces, crutches, canes and change in lifestyle may be necessary. If conservative measures are not successful in providing pain relief, surgery may be indicated to stimulate articular cartilage growth, to replace the joint surfaces, or to fuse the joint preventing joint motion.

Medications

Activity

• Rest is important only during acute phases of the disease when joints are very painful. Resume normal activity as soon as symptoms improve.
• Physical therapy for muscle and joint rehabilitation (severe cases only).
• May need to protect joints from overuse (crutches, cane, walker, elastic knee support).

Diet

If you are overweight, lose weight.

What might complicate it?

An inflammatory arthritis that occurs after osteoarthritis has developed will complicate treatment and recovery. Infection, fracture, contractures, and joint deformity will greatly complicate treatment, as well. Osteoarthritis may, itself, lead to joint fusion from bone overgrowth and spur generation. It is important to note that while the disease is diagnosed by x-ray findings, the symptoms of pain, swelling and stiffness may not correlate well with the findings. For example, an individual's knee films may look horrible, with large spurs, narrow joint space and loose bodies floating in the joint, indicating a long standing problem, and yet the individual may have only mild symptoms or even no symptoms at all. The same individual may have only had symptoms causing him to seek medical care after a seemingly insignificant injury or prolonged activity that aggravated his symptoms. This situation can greatly complicate cases related to cause and effect settlements.

Predicted outcome

Osteoarthritis is a progressive, degenerative disease. Treatment goals should include control of the symptoms of pain, stiffness, and swelling.

Alternatives

Osteochondritis dissecans, osteonecrosis, aseptic necrosis, mechanical joint derangement, infection, chronic inflammatory diseases such as rheumatoid arthritis, systemic lupus erythematosus, and gout are possible diagnoses.

Rehabilitation

Physical therapy (heat packs, ultrasound, electrostimulation, may need an assistance device such as a cane), three times a week for a period of two to four weeks. To control acute symptoms, pool exercise may be helpful.

Appropriate specialists

Rheumatologist, orthopedic surgeon, physiatrist, and anesthesiologist.

Last updated 28 May 2015