This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Orthopaedics
A 7-yr-old boy with abrupt onset of pain in the hip with hip held in the abduction. Hemogram is normal. ESR is raised. What is the next line of management- 
Select and explain. 
A. Hospitalize and observe, B. Ambulatory observation, C. Intravenous antibiotics, D. USG guided aspiration of hip
D: USG guided aspiration of hip
Answer: D: USG guided aspiration of hip 
Explanation: Usually the treatment of a clinically suspected case of transient synovitis of hip is Bed rest, NSAIDS and observation.
USG guided aspiration is indicated for :-


Temperature > 99.5° F
ESR > 20 (Raised ESR)
Severe hip pain with ROM