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

Insights into Imaging

Table 2 Measurement of the ischiofemoral interval depending on femoral torsion and the presence of a quadratus femoris muscle edema on MRI

		Femoral torsion^a			QFM edema
	Overall (N= 121)	High (N = 62)	Normal (N = 59)	p	Present (N = 8)	Absent (N = 113)	p
Proximal intertrochanteric distance (mean in mm ± SD)
Neutral position	40 ± 8	37 ± 8	43 ± 8	<.001*	30 ± 10	41 ± 8	.005*
FABER position	14 ± 9	11 ± 7	17 ± 9	.009*	4 ± 2	15 ± 9	< .001*
Mean difference	26 ± 7	26 ± 7	26 ± 8	.936	26 ± 9	26 ± 7	.831
Distal intertrochanteric distance (mean in mm ± SD)
Neutral Position	28 ± 8	25 ± 7	31 ± 7	<.001*	20 ± 6	28 ± 7	.003*
FABER position	21 ± 9	19 ± 8	24 ± 10	.021*	13 ± 3	22 ± 9	.004*
Mean Difference	6 ± 7	6 ± 7	7 ± 8	.938	7 ± 7	6 ± 7	.871
Ischiofemoral space (mean in mm ± SD)
Neutral position	27 ± 9	23 ± 8	31 ± 10	<.001*	17 ± 5	28 ± 9	< .001*
FABER position	n.a.	n.a.	n.a.	n.a.	n.a.	n.a.	n.a.

^aHigh and normal femoral torsion are defined as > 30°/≤ 30° according to Murphy [16, 17]
Numerical data are mean ± SD. Categorical data are N (%). QFM(E), quadratus femoris muscle (edema); FABER, flexion-abduction-external rotation; n.a., not applicable. *p < .05