Osteoarthritis: Degenerative disease. Obese, athlete, weight bearing joints, DIP> PIP, Herbeden nodescrepitus, stiffness less than 15mins, normal labs, jt space narrowing, osteophytes, bone cysts, dense subchondral bone.
Rheumatoid arthritis: Autoimmune disease. Female, PIP, MCP, wrists,ankles, knees, morning stiffness longer than 30mins, nodules, systemic involvement, Baker cyst, Carpal tunnel syndrome, anti-CCP (sensitive), raised ESR. Most common COD is CAD.
Gout: Metabolic. Male, sudden big toe swelling, pain and redness at night after binge drinking. Tophi, kidney stones, asymptomatic periods.
SLE: Autoimmune. Female. Other features of SLE, normal X ray, present in 90%
Reactive (Reiter's) arthritis: preceeded by an infection by chlamydia, Yersinia, shigella, salmonella or campylobacter. "Can't see, can't pee, can't climb a tree." Uveitis, non gonococcal urethritis, arthritis, archilles tendon pain, circinate balanitis, oral ulcers, nail changes etc Treat the preceeding infection + NSAIDS or Sulfasalazine if no response