​Differential diagnosis of causes of knee effusion

​Differential diagnosis of causes of knee effusion 
-malignant tumor 
-benign tumor 
-hemarthrosis due to bleeding disorder
-osteoarthritis 
-inflammatory osteoarthritis 
-rheumatoid arthritis 
-seronegative spondyloarthropathy 
-reactive arthritis 
-Reiter’s syndrome 
-gout 
-pseudogout 
-infection such as gonoccoal, lyme disease, tuberculosis, staphylococcus aureus 
-trauma,fracture, overuse, ligament injury, meniscal injury