Association of paraspinal muscle water–fat MRI-based measurements with isometric strength measurements
Chemical shift encoding-based water–fat MRI derived proton density fat fraction (PDFF) of the paraspinal muscles has been emerging as a surrogate marker in subjects with sarcopenia, lower back pain, injuries and neuromuscular disorders. The present study investigates the performance of paraspinal muscle PDFF and cross-sectional area (CSA) in predicting isometric muscle strength.
Twenty-six healthy subjects (57.7% women; age: 30 ± 6 years) underwent 3T axial MRI of the lumbar spine using a six-echo 3D spoiled gradient echo sequence for chemical shift encoding-based water–fat separation. Erector spinae and psoas muscles were segmented bilaterally from L2 level to L5 level to determine CSA and PDFF. Muscle flexion and extension maximum isometric torque values [Nm] at the back were measured with an isokinetic dynamometer.
Significant correlations between CSA and muscle strength measurements were observed for erector spinae muscle CSA (r = 0.40; p = 0.044) and psoas muscle CSA (r = 0.61; p = 0.001) with relative flexion strength. Erector spinae muscle PDFF correlated significantly with relative muscle strength (extension: r = -0.51; p = 0.008; flexion: r = -0.54; p = 0.005). Erector spinae muscle PDFF, but not CSA, remained a statistically significant (p < 0.05) predictor of relative extensor strength in multivariate regression models (R2adj = 0.34; p = 0.002).
PDFF measurements improved the prediction of paraspinal muscle strength beyond CSA. Therefore, chemical shift encoding-based water–fat MRI may be used to detect subtle changes in the paraspinal muscle composition.
• We investigated the association of paraspinal muscle fat fraction based on chemical shift encoding-based water–fat MRI with isometric strength measurements in healthy subjects.
• Erector spinae muscle PDFF correlated significantly with relative muscle strength.
• PDFF measurements improved prediction of paraspinal muscle strength beyond CSA.
KeywordsMagnetic resonance imaging Paraspinal muscle Muscle strength
Body mass index
Left erector spinae muscles
Right erector spinae muscles
International Physical Activity Questionnaire
Lower back pain
Muscle fat infiltration
Maximum voluntary isometric contraction
Proton density fat fraction
Left psoas muscle
Right psoas muscle
Root mean square coefficients of variation
Regions of interest
This study has received funding by Philips Healthcare, the German Research Foundation (DFG-SFB824/A9) and TUM Faculty of Medicine KKF grant H01.
Compliance with ethical standards
The scientific guarantor of this publication is Thomas Baum, MD.
Conflict of interest
The authors of this manuscript declare relationships with the following companies: Philips Healthcare.
Statistics and biometry
No complex statistical methods were necessary for this paper.
Written informed consent was obtained from all subjects in this study.
Institutional Review Board approval was obtained.
• Cross-sectional study
• Performed at one institution
- 21.Crawford RJ, Cornwall J, Abbott R, Elliott JM (2017) Manually defining regions of interest when quantifying paravertebral muscles fatty infiltration from axial magnetic resonance imaging: a proposed method for the lumbar spine with anatomical cross-reference. BMC Musculoskelet Disord 18:25CrossRefPubMedPubMedCentralGoogle Scholar