<unk>  is a chronic arthropathy characterized by degeneration of joint cartilage and underlying bone
Alternatively called arthrosis
Most common progressive joint disease
Joints in the hands, knees, hips, and spine are the most frequently affected.
Age (almost exclusively in elderly)
Female versus male sex
Obesity
Lack of osteoporosis
Occupation
Previous injury
Muscle weakness
Genetic elements
Osteoarthritis
Acute osteoarthritis
Rheumatoid arthritis
Avascular necrosis
Ankylosing spondylitis
Crystal-induced 
Reactive arthritis
Gonococcal arthritis, arthritis-dermatitis syndrome