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
[{'content': 'All are true regarding myositis ossificans progressive except - \nSelect and explain. \nA. Usually involve childs, B. Progressive form of normal myositis, C. Respiratory problems, D. Ankylosis', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Myositis ossificans is a misnomer as there is no inflammation in muscles (it is not a form of myositis).\nMyositis ossificans progressive begins in childhood, usually before the age of 6 years.\nThere may be restrictive chest wall disease.\nThere is fusion (ankylosis) of cervical spine.\nBiopsy shows edematous muscle with many inflammatory cells and fragmented myofibrils. Later, true bone forms, often in cartilage, and subsequent mineralizes.', 'role': 'assistant'}]