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Osteoarthritis Overview

Osteoarthritis (OA) is not a single disease but rather the end result of a variety of disorders leading to the structural or functional failure of one or more of your joints. Osteoarthritis is the most common cause of chronic joint pain, affecting over 25 million Americans. Osteoarthritis involves the entire joint, including the nearby muscles, underlying bone, ligaments, joint lining (synovium), and the joint cover (capsule).

  • Osteoarthritis also involves progressive loss of cartilage. The cartilage tries to repair itself, the bone remodels, the underlying (subchondral) bone hardens, and bone cysts form. This process has several phases.
    • The stationary phase of disease progression in osteoarthritis involves the formation of osteophytes and joint space narrowing.
    • Osteoarthritis progresses further with obliteration of the joint space.
    • The appearance of subchondral cysts (cysts in the bone underneath the cartilage) indicates the erosive phase of disease progression in osteoarthritis.
    • The last phase in the disease progression involves bone repair and remodeling.
  • Definitions
    • Joint cartilage is a layer of tissue present at the joint surfaces that sustains joint loading and allows motion. It is gel-like, porous, and elastic. Normal cartilage provides a durable, low-friction, load-bearing surface for joints.
    • Articular surface is the area of the joint where the ends of the bones meet, or articulate, and function like a ball bearing.
    • Bone remodeling is a process in which damaged bone attempts to repair itself. The damage may occur from either an acute injury or as the result of chronic irritation such as that found in osteoarthritis.
    • Collagen is the main supportive protein found in bone tendon, cartilage, skin, and connective tissue.
    • Osteophytes are bony outgrowths or lumps, especially at the joint margins. They are thought to develop in order to offload the pressure on the joint by increasing the surface area on which your weight is distributed.
    • Synovium is a membrane surrounding the joints that secretes a fluid that lubricates and provides nutrition to tissues.
    • Subchondral bone is the part of bone under the cartilage.
    • Osteoarthritis is also known as degenerative joint disease.
    • Related to its effect on joints, osteoarthritis is sometimes referred to as osteoarthrosis.
Medically Reviewed by a Doctor on 8/11/2015

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Learn diet tips that may prevent osteoarthritis.

Diet & Osteoarthritis

Author: William C. Shiel Jr., MD, FACP, FACR

For centuries, we humans have considered that our health is influenced by what we eat. Let's face it, if you eat a taco with hot sauce and have diarrheafollowed by anal burning the next morning, the food affected your body!

The concept that diet can, in any way, affect osteoarthritis (degenerative arthritis) is being evaluated by researchers. Keep in mind that this field is just developing and few hard conclusions can be reached. Here is the latest:

  • Obesityincreases the risk for developing osteoarthritis. Overweight people might reduce their chances for developing or aggravating their osteoarthritis by losing weight. Furthermore, if a person already has substantial osteoarthritis in a weight-bearing joint, such as a knee or hip, weight reduction can significantly improve their ability to rehabilitate after joint surgery as well as decrease their risk of surgical complications.

  • Vitamin C is important in the development of normal cartilage. A deficiency of vitamin C might lead to the development of weak cartilage. Vitamin C is commonly available in citrus fruits. Supplementation with a vitamin C tablet may be advised if dietary fruits are unavailable.

  • People with low bone mineral density, such as in osteoporosis, may be at increased risk for osteoarthritis. Exercise and adequate calcium intake, as recommended for age and gender, can help to maintain bone density.

Read What Your Physician is Reading on Medscape

Osteoarthritis »

Osteoarthritis (OA) is the most common articular disease worldwide, affecting over 20 million individuals in the United States alone.

Read More on Medscape Reference »

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