Osteoarthritis

Overview
Osteoarthritis (OA) is the most common joint disorder, which is due to aging and wear and tear on a joint.  Cartilage that cushions your bones at the joints breaks down and wears away, causing the bones to rub together.

Causes
Aging
Genetics
Being overweight
Trauma earlier in life
Occupational risks
Some sports
Bleeding disorders
Other types of arthritis

Symptoms
Stiffness in the joints, especially in the mornings
Rubbing, grating, or cracking sound
Pain that may worsen with activity

Diagnosis
Physical examination
X-rays

Treatment
Anti-inflammatory drugs
Injections
Skin creams
Application of ice and heat
Lifestyle changes
Physical therapy
Braces
Surgery

Source: https://www.ncbi.nlm.nih.gov/