title: Ischiofemoral impingement: evaluation with new MRI parameters and assessment of their reliability.
abstract: OBJECTIVE
  The aim of this study was to describe the magnetic resonance imaging (MRI) findings in patients with ischiofemoral impingement (IFI) and to evaluate the reliability of these MRI findings.
  
  
  METHODS
  Seventy hips of 50 patients with hip pain and quadratus femoris muscle (QFM) edema and 38 hips of 30 control cases were included in the study. The QFM edema and fatty replacement were assessed visually. Ischiofemoral space (IFS), quadratus femoris space (QFS), inclination angle (IA), hamstring tendon area (HTA), and total quadratus femoris muscle volume (TQFMV) measurements were performed independently by two musculoskeletal radiologists. The intra- and interobserver reliabilities were obtained for quantitative variables.
  
  
  RESULTS
  IFS, QFS, and TQFMV values of the patient group were significantly lower than those of controls (P < 0.001). HTA and IA measurements of the patient group were also significantly higher than in controls (P < 0.05). The QFM fatty replacement grades were significantly higher in the patient group than in the control group (P < 0.001). Inter- and intra-observer reliabilities were strong for all continuous variables.
  
  
  CONCLUSIONS
  Clinicians and radiologists should be aware of IFI in patients with hip or groin pain, and MRI should be obtained for the presence of the QFM edema/fatty replacement, narrowing of the IFS-QFS, and other features that may help in the clinical diagnosis of IFI for the proper diagnosis and treatment of the disease.
authors.affiliation: Department of Radiology, Ankara Ataturk Education and Research Hospital, Bilkent, Ankara, Turkey. drozgurtosun@gmail.com
authors.forename: Ozgur
authors.initials: O
authors.lastname: Tosun
authors.forename: Oktay
authors.initials: O
authors.lastname: Algin
authors.forename: Nadir
authors.initials: N
authors.lastname: Yalcin
authors.forename: Nurdan
authors.initials: N
authors.lastname: Cay
authors.forename: Gokhan
authors.initials: G
authors.lastname: Ocakoglu
authors.forename: Mustafa
authors.initials: M
authors.lastname: Karaoglanoglu
mesh_terms: D018771:Arthralgia / Q000209:etiology*; D004487:Edema / Q000175:diagnosis* / Q000209:etiology; D005260:Female; D006119:Groin / Q000473:pathology; D006621:Hip Joint / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D007592:Joint Diseases / Q000150:complications / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology; D009220:Myositis / Q000175:diagnosis / Q000209:etiology; D016059:Range of Motion, Articular; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D052256:Tendinopathy / Q000175:diagnosis* / Q000209:etiology; D013710:Tendons / Q000473:pathology