This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Injuries Around Shoulder, Subject name: Orthopaedics
[{'content': 'A 40-year-old patient presents with an inability to keep the arm in contact with the chest. When the arm is forcibly brought into contact with the chest there is winging of the scapula. There is a history of repeated intramuscular injections into the deltoid muscle. What is the diagnosis? \nSelect and explain. \nA. Serratus anterior muscle palsy, B. Poliomyelitis, C. Deltoid contracture, D. Neglected anterior dislocation of shoulder', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. C. Deltoid contractureThe above history and examination suggest a diagnosis of deltoid contracture.* Deltoid contracture can be congenital or acquired. Anatomical aberrations, repeated intramuscular injections into the deltoid, chronic infection due to the injected drugs and pressure ischemia are all causes of acquired contracture.* A patient with a deltoid contracture presents with inability to keep his arm in contact with the chest in the anatomical plane of the scapula. When the arm is forcibly brought into contact with the chest there is winging of the scapula. On palpation, a thick intermediate fibrotic deltoid is felt.', 'role': 'assistant'}]