What are the key clinical signs and symptoms of OA? How do these differ from inflammatory arthritis?
OA is characterized by dull joint pain that worsens with activity. Patients often describe stiffness after prolonged immobility (gelling), and creaking/sandy/gritty sensation in the joints. Unlike inflammatory arthritis, morning stiffness lasting over 30 minutes and other systemic signs and symptoms of inflammation are absent. Longstanding inflammatory arthritis can lead to secondary OA; however, deciphering the etiology of a painful joint in this setting (ongoing inflammatory arthritis versus secondary OA) is crucial to ensure proper treatment of the patient. On physical examination, crepitus, bony enlargement, and mild swelling (especially in the knees) may be noted. Joint instability and periarticular muscle atrophy are common.
