Related DDx ⬇
Etiology ⬆
- Trauma, eg, fracture, ligament or meniscal injury, overuse
- Infection, eg, gonococcal, Staphylococcus aureus, Lyme disease, tuberculosis
- Gout or pseudogout
- Seronegative spondyloarthropathy, eg, reactive arthritis (Reiter’s syndrome)
- Rheumatoid arthritis
- Osteoarthritis or inflammatory osteoarthritis
- Hemarthrosis due to bleeding disorder
- Malignant or benign tumor