Hi, I am an American Board Certified Neurologist and I am very glad to help you with your health concerns.
The following are the major differences between rheumatoid arthritis and the ordinary form of arthritis (also called as osteoarthritis).
1) what causes these arthritis - the rheumatoid arthritis is an autoimmune connective tissue disorder or an inflammatory disorder, whereas the osteoarthritis is due to aging process (related to the wear and tear phenomenon) or it may be related to prior traumas or injuries affecting the joint
2) what joints are commonly involved – the rheumatoid arthritis can affect any joint however bilateral involvement of the finger joints is usually an important feature of this type of arthritis. The osteoarthritis generally involves the joints which are commonly used or weight bearing like the knee and hip joints, the spine joints etc
3) severity of the illness – in general the rheumatoid arthritis is more severe and may progress more rapidly than the osteoarthritis, unless properly treated.
4) what else may get involved – the rheumatoid arthritis is considered as a systemic illness so in addition to the joints other parts of the body too may get involved like heart, kidneys, nerves, arteries, or other organs and tissues, whereas the osteoarthritis is not expected to involve any organs or tissues other than the joints
5) diagnosis wise – both show x ray or scan changes; the rheumatoid arthritis can be confirmed with blood tests like RA factor (Rheumatoid factor), raised ESR or CRP in the blood etc, whereas the osteoarthritis does not have any such markers in the blood. A biopsy of the soft tissue structures related to the joint (synovial biopsy) too can be used to help with the diagnosis of rheumatoid arthritis.
6) treatment wise – rheumatoid arthritis is treated with symptomatic treatments and also treated commonly with what are called as disease modifying treatments (which may include steroids, immunosuppressive agents etc), whereas the osteoarthritis is commonly treated with symptomatic treatments, nutritional supplements, steroid joint injections, lubricant injection to the joint etc and if these fail then surgical treatments are tried.
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