title: Features of acetabular labral tears on X-ray, magnetic resonance imaging and hip arthroscopy - the observational pilot study.
abstract: BACKGROUND
  To analyze the X-ray and magnetic resonance imaging (MRI) features of acetabular labral tears, so as to improve the recognition of the disease.
  
  
  METHODS
  Imaging features of 19 patients with acetabular labral tears confirmed by arthroscopy were analyzed retrospectively. All cases were examined by X-ray. Fourteen patients underwent MRI examinations.
  
  
  RESULTS
  Seventeen of the 19 patients had at least one osseous abnormality consistent with femoroacetabular impingement (FAI) under arthroscopy; among them 7 cases were cam impingement, 3 cases were pincer impingement and 7 cases were mixed impingement. X-ray manifestations: 12 of the 19 patients had FAI; among them 6 cases were cam impingement, 2 cases were pincer impingement and 4 cases were mixed impingement. Five cases showed various degrees of degenerations of hip joint. Two patients had no identifiable structural abnormalities. Magnetic resonance imaging showed various degrees of injury of labrum in 6 patients, joint effusion in 5 cases, and bone marrow edema of femoral head in 3 cases.
  
  
  CONCLUSIONS
  The FAI has much to do with acetabular labral tears. X-ray examination is important for FAI diagnosis. Given its high sensitivity and accuracy, MRI is an effective preoperative tool for defining the location and extent of labral tears. Combined with X-ray imaging and clinical manifestation, MRI can provide a reliable basis for clinical diagnosis and treatment of acetabular labral tears.
authors.affiliation: Department of Sports Medicine, Huashan Hospital, Fudan University, Shanghai, China.
authors.forename: Xi-Liang
authors.initials: XL
authors.lastname: Shang
authors.forename: Jia-Wen
authors.initials: JW
authors.lastname: Zhang
authors.forename: Ji-Wu
authors.initials: JW
authors.lastname: Chen
authors.forename: Yun-Xia
authors.initials: YX
authors.lastname: Li
authors.forename: Shi-Yi
authors.initials: SY
authors.lastname: Chen
keywords: acetabular labral tears; arthroscopy; femoroacetabular impingement; magnetic resonance imaging