Imaging parameters of ischiofemoral impingement - a systematic review

Abstract

Ischiofemoral impingement is a recently identified cause of hip pain, but, despite the recognized importance of imaging modalities in its detection, accurate diagnosis remains a challenge. This systematic review examined studies that evaluated qualitative and quantitative imaging parameters that may aid in the prediction of ischiofemoral impingement in adults. PRISMA guidelines were followed, and two databases, MEDLINE (PubMed) and Web of Science, were searched without date restriction. The final review included 24 highly heterogeneous studies. Studies quality was assessed using the National Heart, Lung and Blood Pressure Institute Study Quality Assessment Tools. Regarding qualitative imaging findings, eight studies found oedema, atrophy and/or tear of quadratus femoris, hamstring, iliopsoas and/or gluteus muscles. All of studies found quantitative parameters, with ischiofemoral space and quadratus femoris space being the most evaluated. Other quantitative imaging parameters associated with ischiofemoral impingement were hamstring tendon area, total quadratus femoris muscle volume, femur neck angle, femur neck version, the angle between femur neck version and lesser trochanter version, pelvic width, and ischial angle. In relation to femoral offset, inclination angle, and inter-tuberous distance, there was no consistent finding among studies. Less trochanter version was found not to be associated with ischiofemoral impingement. Moreover, seven studies found that adduction, extension and/or external rotation of the hip were also associated with the development of ischiofemoral impingement. Clinical Significance: Ischiofemoral impingement patients vary in hip morphology and kinematics, with imaging having a crucial role in this diagnose.