The National Institute of Arthritis and Musculoskeletal and Skin Disease define a healthy joint as one in which the ends of the bones are covered by a smooth casing of cartilage. They are further encapsulated by what is called the synovial membrane and synovial fluid--which cushions movement and prevents the cartilage, muscles and connective tissue from damage. In an unhealthy joint--deterioration to this cushion system causes bone on bone rubbing and permanent, painful damage.
Osteoarthritis
According to the National Institute of Arthritis and Musculoskeletal and Skin Disease, osteoarthritis either results because of the general "wearing out" process in aging--or because of an injury. In either scenario, there is a compromise of cartilage covering the ends of bones which connect to forma a joint. Particles of bone or cartilage can end up breaking off and floating around in the fluid of these joints leading to tremendous aches and pain. Similarly, spurs can grow on the ends of the bones which can create tissue damage, inflammation and increase existing pain.
Rheumatoid Arthritis
The Centers for Disease Control and Prevention suggest that rheumatoid arthritis--also referred to as RA--is an autoimmune disorder resulting in the painful swelling, redness and tenderness of the joints and digits. RA is a genetically heritable disease found primarily in Native American ancestry and can strike at any age depending on environmental or accidental influences.
Autoimmune Diseases-Not Otherwise Specified
Other autoimmune deficiencies--besides RA--are also linked to causes of joint and muscle aches. The Merck Manual Home Edition suggests that autoimmune disorders comprise a malfunctioning immune system in which the body tissues are considered foreign antigens--or bacterium--that the body must produce antibodies to attack. Systemic lupus, diabetes, vasculitis, anemia, multiple sclerosis, Hashimoto's thyroiditis, Graves' disease, and Good Pasture's syndrome are but a few examples of autoimmune disorders which can increase joint aches and pain due to swelling.
References
- National Institute of Arthritis and Musculoskeletal and Skin Diseases:"Osteoarthritis"; May 2006
- Centers for Disease Control and Prevention:"Arthritis Basics, Definition Rheumatoid Arthritis"; Oct 2009
- "Merck Manual Home Edition: Autoimmune Disorders"; Jul 2007
- American Autoimmune Related Diseases Assoc. Online Support Group
