Age - 6 mo to 8 yrs
Hematogenous spread or local infection
Staph, S. Pneumo, group A strep
Neonates: also Group B strep and gram negatives
Septic arthritis of the hip 
Acute rheumatic fever
Hip bursitis
Developmental dysplasia of hip
Avascular necrosis of hip
Femur fracture
Lens dislocation
Juvenile idiopathic arthritis