title: [Analysis of the causes of X-ray misdiagnosis of avascular femur head necrosis].
abstract: OBJECTIVE
  To study the cause of X-ray misdiagnosis of the avascular femur head necrosis, so as to reduce the misdiagnosis rate and raise the early diagnosis level.
  
  
  METHODS
  The clinical and X-ray data of 99 patients(123 hips) with avascular femur head necrosis diagnosed by MRI were analyzed retrospectively. Among the patients, 56 patients were male and 43 patients were female,ranging in age from 21 to 84 years old,with an average of 53 years old. The patients had symptoms such as hip pain,functional restriction in flexion, adduction, abduction and internal rotation,and some patients had limping. The duration of the disease ranged from 1 week to 2 years.
  
  
  RESULTS
  Among 99 patients(123 hips),46 patients(52 hips) was misdiagnosed by the X-ray, the misdiagnosis rate was 42.27%, 100.00% in 0 stage, 100.00% in I stage, 83.67% in II stage, 18.18% in II stage, 0.00% in IV stage, 0.00% in V stage; the X-ray stage was negatively correlated with the rate of misdiagnosis. The careless film-reading and invigorating large enterprises while relaxing control over small ones was the main reason of misdiagnosis,then the lack of clinical histories and low-quality of X-ray projection.
  
  
  CONCLUSIONS
  The relevant clinical history and comprehensive careful film-reading is the key to reduce the rate of misdiagnosis.
authors.affiliation: Department of Radiology, People's Hospital of Jiangshan, Quzhou 324100, Zhejiang, China.
authors.forename: Xi-Yuan
authors.initials: XY
authors.lastname: Wu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003951:Diagnostic Errors; D005260:Female; D005271:Femur Head Necrosis / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011859:Radiography; D014965:X-Rays