Osteoarthritis is commonest cause of knee pain and discussed here. Osteoarthritis is one of the commonest joint problems with 80% of general population of radiologic evidence of osteoarthritis by 65 yrs of age. The disease process starts by age of around 20 yrs and manifest around 40 yrs. More than 40% of sufferers have no radiological evident of osteoarthritis.
Exact etiology is not known. By chemical stress on articular cartilage and subchondral bone leads to wear and tear to these structures. Joint inflammation is very minimum compare to other arthritis and seen mostly in advanced disease. Pain of osteoarthritis may be due to following reasons:
Pain around the joint that increases with weight bearing and movement and improves with rest is the commonest presenting symptom. It may be associated with morning stiffness and swelling of the joints. Clinical signs are tenderness, crepitus, joint effusion, decreased range of movement, valgus/varus deformity etc. X-ray shows decreased joint space, osteophytes formation and osteoporosis of subchondral bone.
X-Ray of Osteo-arthritis of Knee