Diagnostic Effectiveness of Ischiofemoral Space and Quadratus Femoris Distance Measurements in Ischiofemoral Impingement Syndrome

Objective: To ascertain whether measurements of the quadratus femoris and ischiofemoral intervals obtained on pelvic magnetic resonance imaging (MRI) examinations are useful for diagnosing ischiofemoral impingement (IFI) syndrome. Methods: MRIs of 178 patients (104 females and 74 males) were reinterpreted bilaterally for signal changes on T2-weighted sequences in the ischiofemoral space (IFS) and quadratus femoris space (QFS), indicating IFI. Receiver operating characteristic (ROC) curves were plotted for each measurement parameter, and the corresponding area under the curve (AUC) values were reported. A P value of less than 0.05 was considered to indicate a significant difference, and the results were assessed at the 95% confidence level. Results: There was no significant difference in age between females and males (P = 0.064). Radiologically, 17.7% of all participants were diagnosed with IFI. Significant differences were observed between IFS and obturator femoris space values by gender, with both values being significantly lower in women. A higher percentage of patients testing positive for IFI was observed in women compared with men. In the ROC analysis conducted according to IFS, the AUC was 0.840. The highest value of sensitivity × specificity was 21.29 mm. The sensitivity at this value was 0.676. The specificity at this value was 0.857. In the ROC analysis using QFS, the AUC was 0.856. The highest value of (sensitivity × specificity) was 16.17 mm. The sensitivity at this value was 0.765. The specificity at this value was 0.794. Conclusion: The results of the current study indicated a significant relationship between the IFS and QFS measurements and IFI. These intervals showed a significant negative correlation with age. This study also identified important cut-off values for IFS and QFS intervals that indicate IFI, with relatively high sensitivity and specificity.