Find information on thousands of medical conditions and prescription drugs.

Osteoarthritis

Osteoarthritis (OA, also known as degenerative arthritis or degenerative joint disease, and sometimes referred to as "arthrosis" or "osteoarthrosis"), is a condition in which low-grade inflammation results in pain in the joints, caused by wearing of the cartilage that covers and acts as a cushion inside joints. As the bone surfaces become less well protected by cartilage, the patient experiences pain upon weight bearing, including walking and standing. Due to decreased movement because of the pain, regional muscles may atrophy, and ligaments may become more lax. OA is the most common form of arthritis. more...

Home
Diseases
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
Obesity
Obsessive-compulsive...
Occipital horn syndrome
OCD
Ochronosis
Oculocutaneous albinism,...
Oculopharyngeal muscular...
Odontophobia
Odynophobia
Oikophobia
Olfactophobia
Olivopontocerebellar atrophy
Omenn syndrome
Onchocerciasis
Oncocytoma
Ondine's curse
Opportunistic infections
Oppositional defiant...
Optic atrophy
Optic neuritis
Oral leukoplakia
Ornithosis
Orthostatic intolerance
Osgood-Schlatter disease
Osteitis deformans
Osteoarthritis
Osteochondritis
Osteochondritis dissecans
Osteochondroma
Osteogenesis Imperfecta
Osteomalacia
Osteomyelitis
Osteopetrosis, (generic...
Osteoporosis
Osteosclerosis
Otosclerosis
Otospondylomegaepiphyseal...
Ovarian cancer
P
Q
R
S
T
U
V
W
X
Y
Z
Medicines

The word is derived from the Greek word "osteo", meaning "of the bone", "arthro", meaning "joint", and "itis", meaning inflammation, although many sufferers have little or no inflammation.

OA affects nearly 21 million people in the United States, accounting for 25% of visits to primary care physicians, and half of all NSAID (Non-Steroidal Anti-Inflammatory Drugs) prescriptions. It is estimated that 80% of the population will have radiographic evidence of OA by age 65, although only 60% of those will be symptomatic (Green 2001). Treatment is with NSAIDs, local glucocorticoid injections, and in severe cases, with joint replacement surgery. There is no cure for OA, as it is impossible for the cartilage to grow back.

Signs and symptoms

The main symptom is chronic pain, causing loss of mobility and often stiffness. "Pain" is generally described as a sharp ache, or a burning sensation in the associated muscles and tendons. OA can cause a crackling noise (called "crepitus") when the affected joint is moved or touched, and patients may experience muscle spasm and contractions in the tendons. Occasionally, the joints may also be filled with fluid. Humid weather increases the pain in many patients.

OA commonly affects the hand, feet, spine, and the large weight-bearing joints, such as the hips and knees, although in theory, any joint in the body can be affected. Progressive degeneration of cartilage, technically known as synovium (joint lining), in the knees can lead to them curving outwards in a condition known as "bow legged". As OA progresses, the affected joints appear larger, are stiff and painful, and usually feel worse, the more they are used throughout the day, thus distinguishing it from rheumatoid arthritis.

In smaller joints, such as at the fingers, hard bony enlargements, called Heberden's nodes and/or Bouchard's nodes, may form, and though they are not necessarily painful, they do limit the movement of the fingers significantly. OA at the toes leads to the formation of bunions, rendering them red or swollen.

Causes of disease

The crucial factor in the development of OA is the wearing out and eventual disappearance of synovium, and later, all cartilage of the affected joints. OA may be divided into two types:

  • Primary OA: This type is caused by ageing. As a person ages, the water content of the cartilage increases, and the protein composition in it degenerates, thus degenerating the cartilage through repetitive use or misuse. Inflammation can also occur, and stimulate new bone outgrowths, called "spurs" (osteophyte), to form around the joints. Sufferers find their every movement so painful and debilitating that it can also affect them emotionally and psychologically.
  • Secondary OA: This type is caused by other diseases or conditions such as:
    • obesity. Obesity puts added weight on the joints, especially the knees.
    • diabetes
    • repeated trauma. Certain sports, such as weightlifting, or even football, put undue pressure on the knee joints.
    • hormonal disorders
    • osteoporosis
    • surgery to the joint structures
    • congenital hip luxation (which is genetically determined)
    • inflammatory diseases (such as Perthes' disease), and all chronic forms of arthritis (e.g. rheumatoid arthritis and gout). In gout, uric acid crystals cause the cartilage to degenerate at a faster pace.
    • People with abnormally-formed joints are more vulnerable to OA, as added stress is specifically placed on the joints whenever they move.
    • Ligamentous deterioration or instability may be a factor.

OA often affects multiple members of the same family, suggesting that there is a hereditary basis for this condition. A number of studies have shown that the there is a greater prevalence of the disease between siblings, and especially twins, indicating a hereditary basis. In the population as a whole up to 60% of OA is thought to be as a result of genetic factors.

Read more at Wikipedia.org


[List your site here Free!]


Chondroitin in patients with severe knee osteoarthritis
From American Family Physician, 7/15/05 by Henry Barry

Clinical Question: Is chondroitin sulfate effective in relieving pain or preventing the progression of osteoarthritis of the knee in patients with severe disease?

Setting: Outpatient (specialty)

Study Design: Randomized controlled trial (double-blinded)

Allocation: Concealed

Synopsis: Patients 40 to 85 years of age with clinically symptomatic osteoarthritis of the knee (according to American College of Rheumatology criteria) were eligible to participate in this study unless they had severe changes on radiography (i.e., severely narrowed joint space with sclerosis of the subchondral bone). Those who had secondary osteoarthritis or the most severe symptoms were excluded. Patients were assigned randomly to receive 800 mg of chondroitins 4 and 6 sulfate (n = 150) or placebo (n = 150) daily for two years.

The main outcomes, assessed via intention to treat, were radiographic progression and symptom relief as measured by the Western Ontario and McMaster Universities Osteoarthritis Index. Participants and study personnel did not know to which group the patients were assigned until the conclusion of the study.

Although only 219 patients (73 percent) completed the two-year study, the researchers carried forward the final observation and performed radiography at the time each patient dropped out. At the end of two years, patients taking chondroitin experienced no change in joint space width from baseline; in the patients taking placebo, joint space narrowed by an average of 0.14 mm ([+ or -] 0.57 mm; P = .04). It appears that chondroitin protected the joint from further deterioration. However, it had no effect on pain.

Bottom Line: After two years of treatment, chondroitin sulfate has no effect on comfort in patients with severe degenerative arthritis of the knee. Compared with placebo, however, it appears that chondroitin may have a small protective effect on the joint. The clinical relevance of this effect is not known. (Level of Evidence: 1b)

Study reference: Michel BA, et al. Chondroitins 4 and 6 sulfate in osteoarthritis of the knee: a randomized, controlled trial. Arthritis Rheum March 2005;52:779-86.

Used with permission from Barry H. Chondroitin ineffective for pain relief in patients with severe knee OA. Accessed online April 27, 2005, at: http://www.InfoPOEMs.com.

COPYRIGHT 2005 American Academy of Family Physicians
COPYRIGHT 2005 Gale Group

Return to Osteoarthritis
Home Contact Resources Exchange Links ebay