Ischiofemoral Impingement Syndrome: A Case Report and a Review of Literature

The quadratus femoris muscle anatomy: Do we know everything?

INTRODUCTION

The purpose of this study was to characterize the morphological variations in the quadratus femoris muscle (QF) and to create an anatomical classification that could be used in the planning of surgical procedures in this area, radiological imaging, and rehabilitation.

MATERIALS AND METHODS

Ninety-two lower limbs from 46 cadavers, fixed in 10% formalin solution, were examined.

RESULTS

The QF muscle was present in all specimens. According to morphology, the QF muscle was classified into three types. The most common type was Type I, characterized by one muscular belly (78.3%), while the second most common type was Type II, characterized by two bellies, was observed in 17.4% of cases. The rarest type was Type III. It was characterized by three bellies and was found in 4.3% of the cases.

CONCLUSIONS

The current classification system on quadratus femoris morphological variability is novel. Morphological variants may contribute to clinical issues, such as the ischiofemoral impingement syndrome, that could arise from type I quadratus femoris. Hence, the current study may be applicated to planning surgical procedures, imaging, and rehabilitation.

MRI measurement assessment on ischiofemoral impingement syndrome

BACKGROUND

To explore the value of MRI upon diagnosis of ischiofemoral impingement syndrome (IFI) and to recognise deformation or oedema of the quadratus femoris muscle. MRI applied to measure the ischial femoral space (IFS), the average width of quadratus femoral space (QFS), and the ischial intertuberal diameter.

METHODS

A retrospective analysis was carried out of 213 hip joints MRI images of 58 cases diagnosed with IFI and 61 cases of normal subjects. IFS, QFS and ischial intertuberal diameter were measured by axial T1WI sequence. The morphological and signal changes of the quadratus femoris muscle were observed through proton density weighted image fat suppression sequence (PDWI-FS).

RESULTS

The widths of IFS and QFS in the normal group were larger than those in the case group, while the ischial intertuberal diameter was significantly smaller (p < 0.05). Pearson correlation analysis revealed that there was a positive correlation (r = 0.824) between IFS and QFS in all hip joints and a negative correlation between the ischial intertuberal diameter and the widths of IFS and QFS (r = -0.213, -0.222, p < 0.05) respectively. As the grade of oedema in quadratus femoris muscle increased, the corresponding IFS gradually decreased. The corresponding IFS width of grade 0 oedema of the quadratus femoris muscle oedema was significantly higher than that of grade 1, grade 2 and grade 3. The receiver operating characteristic curve (ROC) of the subjects was applied to determine the diagnostic boundary value of the IFS and QFS in IFI patients, which was 1.98 cm and 1.05 cm respectively. The area under the curve (AUC) was 0.948 and 0.953 respectively.

CONCLUSIONS

MRI examination could provide a reliable basis for the diagnosis of ischiofemoral impingement syndrome. The narrowing of IFS and QFS with deformation and oedema in the quadratus femoris muscle may be the features of manifestation of IFI.

Ischiofemoral impingement syndrome: a case report and review of literature

Introduction

The etiology of ischiofemoral impingement (IFI) syndrome, an unusual and uncommon form of hip pain, remains uncertain. Some patients demonstrate narrowing of the space between the ischial tuberosity and lesser trochanter from trauma or abnormal morphology of the quadratus femoris muscle. Combined clinical and imaging aid in the diagnosis.

Case report

A 32-year-old female presented with a 3 years history of pain over the lower aspect of the right buttock, aggravated by movements of the right hip, and partially relieved with rest and medications. The right hip showed extreme restriction of abduction and external rotation. MRI of the right hip showed reduced ischiofemoral space and quadratus femoris space when compared to the left hip. The patient underwent endoscopic resection of the right lesser trochanter, with no recurrence of pain at 2 years.

Conclusion

An unusual cause of hip pain, IFI syndrome, should be suspected when hip pain at extremes of movement is associated with signal abnormality of quadratus femoris muscle. Management is tailored to address the inciting factors that precipitated the IFI syndrome.

Normal Ischiofemoral Distance and Its Associated Factors: Computed Tomography-Based Study

PURPOSE

The purposes of this study are (1) to measure the ischiofemoral distance (IFD) in nondiseased hips and (2) to reveal patient demographic and anatomical factors associated with IFD.

METHODS

In this retrospective study, we identified patients who had unilateral osteonecrosis of the femoral head on computed tomography (CT) scan from November 2005 to July 2018 and assessed the unaffected contralateral hips of the patients. Among the contralateral hips, we excluded hips with hip pain, incomplete or poor-quality CT image, incomplete medical record, degenerative arthritis of the hip, or previous hip surgery. IFD was measured on the axial CT image, and correlated demographic factors (age, sex, height, weight, and body mass index) and anatomical parameters (neck-shaft angle of the femur and femoral anteversion) with IFD were evaluated.

RESULTS

Five hundred seventeen patients (517 hips) were evaluated. There were 302 men and 215 women, and their mean age was 51.7 years (range 15-83 years). The mean IFD was 33.2 (±9.2) mm in men and 24.3 (±8.9) mm in women (P < .001). Interobserver and intraobserver reliability (intraclass correlation coefficients) were 0.99 (95% confidence interval 0.98-1.0) and 0.98 (95% confidence interval 0.97-0.99), respectively. The mean neck-shaft angle was 129.31° ± 5.04° in males and 129.93° ± 6.29° in females. The mean femoral anteversion was 9.72° ± 7.95° in males and 12.61° ± 8.91° in females. IFD was positively correlated with height (correlation coefficient [r] = 0.464, P < .001) and weight (0.286, P < .001), whereas it was negatively correlated with age (-0.198, P < .001), neck-shaft angle (-0.123, P = .005), and femoral anteversion (-0.346, P < .001). There was no correlation between body mass index and IFD (P = .522). In multivariate regression analysis, IFD was positively associated with height (β = .632), and negatively associated with neck-shaft angle of the femur and femoral anteversion (β = -0.155 and -0.328. respectively).

CONCLUSIONS

In asymptomatic hips, the mean IFD was 33.2 ± 9.2 mm in males and 24.3 ± 8.9 mm in females. The IFD was positively correlated with height and negatively with neck-shaft angle of the femur and femoral anteversion.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Variability of ischiofemoral space dimensions with changes in hip flexion: an MRI study

OBJECTIVE

The primary aim of this study was to determine if ischiofemoral space (IFS) dimensions vary with changes in hip flexion as a result of placing a bolster behind the knees during magnetic resonance imaging (MRI). A secondary aim was to determine if IFS dimensions vary between supine and prone hip neutral positions.

DESIGN

The study employed a prospective design.

SETTING

Sports medicine center within a tertiary care institution.

PARTICIPANTS

Five male and five female adult subjects (age mean = 29.2, range = 23-35; body mass index [BMI] mean = 23.5, range = 19.5-26.6) were recruited to participate in the study.

METHODS

An axial, T1-weighted MRI sequence of the pelvis was obtained of each subject in a supine position with their hips in neutral and flexed positions, and in a prone position with their hips in neutral position. Supine hip flexion was induced by placing a standard, 9-cm-diameter MRI knee bolster under the subject's knees. The order of image acquisition (supine hip neutral, supine hip flexed, prone hip neutral) was randomized. The IFS dimensions were then measured on a separate workstation. The investigator performing the IFS measurements was blinded to the subject position for each image.

MAIN OUTCOME MEASUREMENTS

The main outcome measurements were the IFS dimensions acquired with MRI.

RESULTS

The mean IFS dimensions in the prone position were 28.25 mm (SD 5.91 mm, standard error mean 1.32 mm). In the supine hip neutral position, the IFS dimensions were 25.1 (SD 5.6) mm. The mean difference between the two positions of 3.15 (3.6) mm was statistically significant (95 % CI of the difference = 1.4 to 4.8 mm, t₁₉ = 3.911, p = .001). The mean IFS dimensions in the hip flexed position were 36.9 (SD 5.7) mm. The mean difference between the two supine positions of 11.8 (4.1) mm was statistically significant (95 % CI of the difference = 9.9 to 13.7 mm, t₁₉ = 12.716, p < .001).

CONCLUSIONS

Our findings demonstrate that the IFS measurements obtained with MRI are dependent upon patient positioning with respect to hip flexion and supine versus prone positions. This finding has implications when evaluating for ischiofemoral impingement, an entity resulting in hip and/or buttock pain secondary to impingement of the quadratus femoris muscle within a pathologically narrowed IFS. One will need to account for patient hip flexion and supine versus prone positioning when evaluating individuals with suspected ischiofemoral impingement.

Can Ultrasound Accurately Assess Ischiofemoral Space Dimensions? A Validation Study

BACKGROUND

Ischiofemoral impingement is a potential cause of hip and buttock pain. It is evaluated commonly with magnetic resonance imaging (MRI). To our knowledge, no study previously has evaluated the ability of ultrasound to measure the ischiofemoral space (IFS) dimensions reliably.

OBJECTIVE

To determine whether ultrasound could accurately measure the IFS dimensions when compared with the gold standard imaging modality of MRI.

DESIGN

A methods comparison study.

SETTING

Sports medicine center within a tertiary-care institution.

PARTICIPANTS

A total of 5 male and 5 female asymptomatic adult subjects (age mean = 29.2 years, range = 23-35 years; body mass index mean = 23.5, range = 19.5-26.6) were recruited to participate in the study.

METHODS

Subjects were secured in a prone position on a MRI table with their hips in a neutral position. Their IFS dimensions were then acquired in a randomized order using diagnostic ultrasound and MRI.

MAIN OUTCOME MEASUREMENTS

The main outcome measurements were the IFS dimensions acquired with ultrasound and MRI.

RESULTS

The mean IFS dimensions measured with ultrasound was 29.5 mm (standard deviation [SD] 4.99 mm, standard error mean 1.12 mm), whereas those obtained with MRI were 28.25 mm (SD 5.91 mm, standard error mean 1.32 mm). The mean difference between the ultrasound and MRI measurements was 1.25 mm, which was not statistically significant (SD 3.71 mm, standard error mean 3.71 mm, 95% confidence interval -0.49 mm to 2.98 mm, t₁₉ = 1.506, P = .15). The Bland-Altman analysis indicated that the 95% limits of agreement between the 2 measurement was -6.0 to 8.5 mm, indicating that there was no systematic bias between the ultrasound and MRI measurements.

CONCLUSIONS

Our findings suggest that the IFS measurements obtained with ultrasound are very similar to those obtained with MRI. Therefore, when evaluating individuals with suspected ischiofemoral impingement, one could consider using ultrasound to measure their IFS dimensions.

LEVEL OF EVIDENCE

III.