Osteoarthritis

What is osteoarthritis?
Osteoarthritis is the most common type of arthritis affecting about 16 million Americans, usually middle-aged and older people. This is a noninflammatory degenerative joint disease characterized by the breakdown of the joint's cartilage. Cartilage that cushions the bones of the hip starts to erode, eventually allowing the bones to grind or rub together and causing hip pain and stiffness. The exact cause of osteoarthritis is unknown
Why it causes pain? - cartilage that cushions the bones of the hip starts to erode, eventually allows the bones of the joint to grind or rub together. 
Symptoms: pain and stiffness 
About 16 million affected in USA- (most common type of arthritis) 

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