Z. Perraton1, P. Lawrenson2,3, A. Mosler1, J. Elliott4, K.A. Weber5, J. Cornwall6, R. Crawford7, K. Crossley1, A. Semciw1,8
1La Trobe University, La Trobe Sport and Exercise Medicine Research Centre, Melbourne, Australia, 2University of Queensland, School of Health and Rehabilitation Sciences, Brisbane, Australia, 3University of Otago, Department of Anatomy, School of Biomedical Science, Dunedin, New Zealand, 4The University of Sydney and The Northern Sydney Local Health District, The Kolling Institute, Faculty of Medicine and Health, Sydney, Australia, 5Stanford University School of Medicine, Department of Anesthesiology, Perioperative and Pain Medicine, California, United States, 6The University of Otago, Centre for Early Learning in Medicine, Otago Medical School, Dunedin, New Zealand, 7Body Urbanism Consultancy, Rotterdam, Netherlands, 8Northern Health, Northern Centre for Health, Education and Research, Melbourne, Australia
Background: Optimal function of the lateral hip muscles may be essential to the maintenance of hip joint health.. Knowledge of muscle morphology and composition (e.g., fatty infiltration) can aid in the assessment and management of hip conditions, with such measurements being useful for monitoring pathology or the effects of interventions.
Magnetic resonance imaging (MRI) is increasingly been used for assessment of muscle morphology and composition, however there are currently no standard protocols or guidelines available to synthesise the heterogenous methods currently employed for evaluating these characteristics. Standardised methodology is necessary to guide future studies and allow the synthesis of data across studies to better understand the contribution of muscle morphology and composition to healthy ageing, pathology, symptom progression, and rehabilitation outcomes.
Magnetic resonance imaging (MRI) is increasingly been used for assessment of muscle morphology and composition, however there are currently no standard protocols or guidelines available to synthesise the heterogenous methods currently employed for evaluating these characteristics. Standardised methodology is necessary to guide future studies and allow the synthesis of data across studies to better understand the contribution of muscle morphology and composition to healthy ageing, pathology, symptom progression, and rehabilitation outcomes.
Purpose: This scoping review aims to collate and synthesise current MRI protocols and make recommendations on a standardised method for the MRI assessment of lateral hip muscle morphology and composition.
Methods: Five electronic databases (Medline, CINAHL, Embase, SportDISCUS and AMED) were searched. All musculoskeletal studies that described MRI investigation to assess lateral hip muscle size and fatty infiltration were included. Lateral hip muscles of interest included: tensor fascia latae (TFL), gluteus maximus, gluteus medius, and gluteus minimus. Details on MRI parameters, anatomical region of interest, muscle size and fatty infiltrate protocols were collected.
Results: From 2,560 studies, seventy-five met inclusion criteria for this review. A range of musculoskeletal conditions were identified that used MRI muscle morphology assessment including: hip osteoarthritis, gluteal tendinopathy, and total hip replacement. A range of studies used MRI to assess intervention outcomes for hip-focused rehabilitation programs, and sports and lower limb strength specific exercises.
MRI scanner strength ranged from 1.5 to 3 Tesla. Slice thickness ranged from 3mm to 10 mm, with a third of the studies not reporting thickness. The majority of studies incorporated T1 weighted MRI sequencing. Other sequencing included DIXON, STIR and T2 fat supressed images. Field of view measures ranged from 80 x140mm to 400 x400mm. Muscle size was measured either by cross sectional area (CSA) or by volume. Fatty infiltrate was either measured on a percentage scale or on previously determined five-point Likert-type scales (Goutallier classification system). The anatomical landmarks used to report on individual muscle characteristics were inconsistent and highly variable, such as CSA reference levels for gluteus minimus which were variably reported at the anterior inferior iliac spine, upper border of the acetabulum, and below the ipsilateral sacroiliac joint.
MRI scanner strength ranged from 1.5 to 3 Tesla. Slice thickness ranged from 3mm to 10 mm, with a third of the studies not reporting thickness. The majority of studies incorporated T1 weighted MRI sequencing. Other sequencing included DIXON, STIR and T2 fat supressed images. Field of view measures ranged from 80 x140mm to 400 x400mm. Muscle size was measured either by cross sectional area (CSA) or by volume. Fatty infiltrate was either measured on a percentage scale or on previously determined five-point Likert-type scales (Goutallier classification system). The anatomical landmarks used to report on individual muscle characteristics were inconsistent and highly variable, such as CSA reference levels for gluteus minimus which were variably reported at the anterior inferior iliac spine, upper border of the acetabulum, and below the ipsilateral sacroiliac joint.
Conclusion(s): This review has summarised MRI parameters and anatomical regions of interest for the lateral hip muscles from existing literature. Generated data are intended to support the establishment of a standardised method for examination of lateral hip musculature by MRI.
Implications: Establishing a standardised method for the MRI assessment of lateral hip musculature will aid in the examination of musculoskeletal conditions around the hip joint by facilitating more accurate data synthesis and improvements in the validity of future between studies analyses. This may help further knowledge on disease characteristics, progression of pathology, and muscular response to health, injury and management.
Funding, acknowledgements: Zuzana Perraton is supported by a NHMRC postgraduate scholarship (APP1191009)
Keywords: Hip, MRI, muscle morphology
Topic: Research methodology, knowledge translation & implementation science
Did this work require ethics approval? Yes
Institution: N/A
Committee: N/A
Ethics number: N/A
All authors, affiliations and abstracts have been published as submitted.
