Dr. Lynch

Orthopaedic Surgeon

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Knee Arthritis

Knee Arthritis

What is Knee Arthritis?

Arthritis is a general term covering numerous conditions where the joint surface or cartilage wears out. The joint surface is covered by a smooth articular surface that allows pain-free movement in the joint. This surface can wear out for several reasons; often the definite cause is not known. Arthritis often affects the knee joint.

When the articular cartilage wears out, the bone ends rub on one another and cause pain. This condition is referred to as Osteoarthritis or "wear and tear" arthritis, as it occurs with aging and use. It is the most common type of arthritis.

Causes of Knee Arthritis

There are numerous conditions that can cause arthritis but often the exact cause is never known. In general, but not always, it affects people as they get older (Osteoarthritis).

The causes include:

  • Trauma (fracture)
  • Increased stress such as overuse and overweight
  • Infection of the bone
  • Connective tissue disorders
  • Inactive lifestyle and obesity (overweight). Your weight is the single most important link between diet and arthritis, as being overweight puts an additional burden on your hips, knees, ankles and feet.
  • Inflammation (rheumatoid arthritis)

Symptoms of Knee Arthritis

Knee arthritis causes pain and decreased mobility of the knee joint. In the arthritic knee, there is an absent joint space that shows on X-ray. In the normal knee, there is a normal joint space.

The cartilage lining is thinner than normal or completely absent. The degree of cartilage damage and inflammation varies with the type and stage of arthritis. The capsule of the arthritic knee is swollen. The joint space is narrowed and irregular in outline; this can be seen in an X-ray image. Bone spurs or excessive bone can also build up around the edges of the joint. The combinations of these factors make the arthritic knee stiff and limit activities due to pain or fatigue.

Diagnosis of Knee Arthritis

Doctors diagnose knee arthritis with a medical history, a physical examination and X-rays of the affected joint. During the physical examination, your doctor will examine the affected joint for swelling, pain, tenderness, and assess the joint's range of motion. An X-ray of the knee may show a loss of the joint space and bone spur formation.

There is no blood test for knee arthritis.

Treatment for Knee Arthritis

There is no known cure for knee arthritis. However, there are several treatments and lifestyle modifications that can help you ease your pain and symptoms. The objective of the treatment is to reduce pain, improve joint movement, and prevent further damage to the joint. The treatment of knee arthritis involves:

  • Medications: Medications may include different classes such as anti-inflammatory drugs, steroid injections, artificial joint fluid injections, and other drugs.
  • Lifestyle Modifications : Some of the lifestyle modifications include:
    • A moderate exercise program
    • Use of heat or cold treatments
    • Eating a healthy and well balanced diet
    • Getting adequate rest
    • Losing weight
    • Protecting your joints with the use of assistive devices such as splints or braces to support the weakened joints
  • Physical Therapy : Your physical therapist will teach you exercises to keep joints flexible and improve muscle strength.
  • Surgery: Surgery is usually considered if non-surgical treatment fails to provide relief. Joint replacement surgery is considered as an option when the pain is so severe that it affects your ability to carry out normal activities.

Quick Links

  • American Association of Orthopaedic Surgeons (AAOS)
  • AANA | Arthroscopy Association of North America
  • American Orthopaedic Society for Sports Medicine (AOSSM)
  • The Perry Initiative
  • Tru Ortho