Interpretation of ischiofemoral impingement via a clinical test using hip triaxial dynamic magnetic resonance imaging

Abstract

Background: The present study aimed to use magnetic resonance (MR) to explore the dynamic changes of the ischiofemoral space (IFS) under the triaxial motion of the hip joint and verify the clinical test mechanism for ischiofemoral impingement (IFI).Methods: A prospective design was used to screen 37 patients with clinically confirmed IFI, which included a total of 67 lateral hips, and 39 healthy controls with a total of 69 lateral hips. A dynamic MR examination was performed in positions designed by a simulated IFI test (adduction, adduction with 30° external rotation, 30° internal rotation, supine with 30° flexion, and prone with 30° backward extension). The IFS (mm) and quadratus femoris space (QFS, mm) were measured in different positions. All the data were evaluated independently by three musculoskeletal radiologists. The differences between the two groups were compared using the two-tailed t-test. Results:The IFS and QFS in the case group were smaller than those in the control group. The IFS and QFS were significantly reduced in the prone with backward extension and adduction with external rotation positions of the hip. The correlation coefficients of the IFI test and long-stride walking (LSW) test were -0.621 and -0.715 for IFS and -0.653 and -0.696 for QFS, respectively.Conclusions: In this study, the mechanism of the IFI-specific clinical examination (IFI and LSW tests) was verified by triaxial dynamic MR imaging of the hip joint, which provided a dynamic imaging basis for the clinical application of the IFI-specific impingement test. The IFI impingement test can be used as a specific clinical test for IFI screening.

A novel method for in vivo measurement of dynamic ischiofemoral space based on MRI and motion capture

“…The results show that the largest ischiofemoral space measurement occurred with the hip in the abduction and internal rotation (51.8 mm; 95% confidence interval [CI], 49.2–54.5 mm), whereas hip adduction and external rotation resulted in the narrowest ischiofemoral space measurement (30.8 mm; 95% CI, 25.5–36.0 mm). Li and his colleagues ( Li et al, 2022 ) used repeated MRI to examine IFS and QFS in different positions. They found that the IFS and QFS were significantly reduced in the prone with backward extension and adduction with external rotation positions of the hip.…”

“…The quadratus femoris space could also be evaluated using the ischiofemoral space (IFS) ( Huang et al, 2022 ), which is a bone-to-bone distance indicating the shortest distance between the lateral cortex of the ischial tuberosity and the medial cortex of the lesser trochanter of the femur. However, the traditional measurement methods are based on static methods, such as repeated X-ray, MRI, or CT ( Park et al, 2016 ; Johnson et al, 2017 ; Shoji et al, 2017 ; Li et al, 2022 ), to measure IFS in different postures which do not reflect a complete bone movement process. The walking activity of the hip joint depends on the dynamic interaction between the pelvis and femur, and the changes of the bone-to-bone distance during the movement state can reflect the patient’s movement mechanism more comprehensively.…”

Hip MRI in flexion abduction external rotation for assessment of the ischiofemoral interval in patients with hip pain—a feasibility study

“…Previous attempts to improve the understanding of the pathomechanics in IFI using MRI have demonstrated dynamic, position-dependent changes [ 25 , 26 ]. Vincentini et al investigated the effect of external rotation on IFS dimension with kinematic MRI.…”

“…They reported narrowing of the IFS in the supine position when moving from 30° internal rotation (25 ± 7 mm) to combined adduction and external rotation (11 ± 3 mm). In addition, they also reported narrowing of the IFS in the prone position during 30° extension (9 ± 3 mm) [ 26 ].…”