| Term | Definition |
| Reumatoid Arthritis | Boutoniere and Swan Neck Deformities, HLA DR4 |
| Heberden's nodes (DIP), Bouchard's nodes (PIP) | Osteoarthritis |
| pain with use, limited morning stiffness | Osteoarthritis |
| Rheumatoid Arthritis | significant morning stiffness improve with use |
| Septic Arthritis | Staph Aureus, Streptococcus, Neisseria gonorrhoeae |
| Gonococcal arthritis | monoarticular, migratory arthritis, asymmetric |
| Chronic infectious arthritis | TB, Lyme Disease |
| Joint is swollen, red, and painful | Infectious, Gout |
| Gout | painful MTP joint of the big- Podagra |
| Gout | precipitation of urate crystals in joints due to hyperuricemia, negetively birefringent |
| Exogenous causes of gout | alcohol, thiazide diuretics, large meal |
| Pseudogout | deposition of calcium pyrophosphate crystals with the joint, weakly positively birefringent |
| Spondyloarthropathies | Arthritis without rheumatoid factor, HLA B27 |
| Ankylosing spondylitis | inflammatory disease of SI joints and spine, stiff spine, uveitis, aortic regurg |
| Reiter's syndrome | conjuctivitis, urethritis, arthritis, Post chlam or GI infections |
| Psoriatic arthritis | joint pain, psoriasis, sausage fingers (dactylitis), pencil in cup deformity on X-ray |
| Osteoarthritis | X-ray- narrowed joint space, osteophytes, subchondral cysts, sclerosis |
| Lyme disease | erythema chronicum migrans, bilateral bell's palsy, myocarditis, arthritis |