Factors Distinguishing Septic Arthritis from Transient Synovitis of the Hip in Children

This prospective study of children who presented with findings that were highly suspicious for septic arthritis of the hip builds on the work of previous authors. We found fever (an oral temperature >38.5 degrees C) was the best predictor of septic arthritis followed by an elevated C-reactive protein level, an elevated erythrocyte sedimentation rate, refusal to bear weight, and an elevated serum white blood-cell count. In our study group, a C-reactive protein level of >2.0 mg/dL (>20 mg/L) was a strong independent risk factor and a valuable tool for assessing and diagnosing children suspected of having septic arthritis of the hip.