This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pediatric Ohopedics, Subject name: Orthopaedics
[{'content': 'Causes of a painless limp in infancy includes: \nSelect and explain. \nA. Congenital dislocation of hip, B. Infantile coxa vara, C. Poliomyelitis, D. All of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Painless Limp Painful Limp 1-3 years age group: DDH Cerebral palsy Muscular dystrophy Infantile coxa vara 4-10 years age: Limb length discrepancy Poliomyelitis Legg Calve Pehes disease Slipped capital femoral epiphysis Osteochondritis dissecans -Lateral surface of medial femoral condyle Ahritis/Synovitis/Osteomyelitis', 'role': 'assistant'}]