This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pediatric orthopedics, Subject name: Orthopaedics
Causes of Psedoahrosis is all of the following except - 
Select and explain. 
A. Idiopathic, B. multiple compound Fractures, C. Osteomyelitis, D. Neurofibromatosis
C: Osteomyelitis
Answer: C: Osteomyelitis 
Explanation: Pseudoahrosis is pseudo joints * it can be seen after a fracture - non union of a fracture may be painless if pseudojoint forms between fracture ends. *it can be idiopathic *can be seen in neurofibromatosis *congenital pseudoahrosis of tibia - rare condition , in 50-90% cases neurofibromatosis is present * in established cases - Boyd dual onlay graft is the treatment of choice in patients with street fracture. REF:textbook of ohopedics, John ebnezer, 4th edition ,pg.no.501