Distinguishing Rheumatoid Arthritis from Osteoarthritis

Morning Stiffness Duration

Morning stiffness in RA typically lasts 1 hour or longer, reflecting the significant inflammatory process that occurs during periods of inactivity, according to the American College of Rheumatology 3, 4
OA morning stiffness is typically mild and brief, usually lasting less than 30 minutes 5, 6, 3
The duration of morning stiffness is considered an important differentiating feature between RA and OA, with a threshold of at least 1 hour being characteristic of RA 3, 4

RA characteristically presents with symmetric involvement of multiple joints, particularly affecting metacarpophalangeal (MCP), proximal interphalangeal (PIP), and wrist joints, according to the American College of Rheumatology 1, 2
A higher number of tender and swollen joints with symmetrical involvement is strongly associated with RA, as recommended by the American College of Rheumatology 1, 2
OA typically affects one or a few joints at any one time with symptoms that are often intermittent 5, 6

Prior hand injury is actually listed as a risk factor for osteoarthritis, not rheumatoid arthritis, according to the Annals of the Rheumatic Diseases 7, 6
OA risk factors include occupation or recreation-related joint usage and prior joint injury, as stated by the American Academy of Orthopaedic Surgeons 7, 6

RA primarily targets MCP and PIP joints while typically sparing distal interphalangeal (DIP) joints, as noted by the American College of Rheumatology 5
OA commonly affects DIP joints (Heberden nodes), PIP joints (Bouchard nodes), and thumb base, according to the American Academy of Orthopaedic Surgeons 7, 5