3T-MRI-based age, sex and site-specific markers of musculoskeletal health in healthy children and young adults

Objective: The aim of this study is to investigate the role of 3T-MRI in assessing musculoskeletal health in children and young people. Design: Bone, muscle and bone marrow imaging was performed in 161 healthy participants with a median age of 15.0 years (range, 8.0, 30.0). Methods Detailed assessment of bone microarchitecture (constructive interference in the steady state (CISS) sequence, voxel size 0.2 x 0.2 x 0.4 mm(3)), bone geometry (T1-weighted turbo spin echo (TSE) sequence, voxel size 0.4 x 0.4 x 2 mm(3)) and bone marrow (1H-MRS, point resolved spectroscopy sequence (PRESS) (single voxel size 20 x 20 x 20 mm(3)) size and muscle adiposity (Dixon, voxel size 1.1 x 1.1 x 2 mm(3)). Results: There was an inverse association of apparent bone volume/total volume (appBV/TV) with age (r = -0.5, P < 0.0005). Cortical area, endosteal and periosteal circumferences and muscle cross-sectional area showed a positive association to age (r > 0.49, P < 0.0001). In those over 17 years of age, these parameters were also higher in males than females (P < 0.05). This sex difference was also evident for appBV/TV and bone marrow adiposity (BMA) in the older participants (P < 0.05). App BV/TV showed a negative correlation with BMA (r = -0.22, P= 0.01) which also showed an association with muscle adiposity (r = 0.24, P= 0.04). Cortical geometric parameters were highly correlated with muscle area (r > 0.57, P < 0.01). Conclusions: In addition to providing deep insight into the normal relationships between bone, fat and muscle in young people, these novel data emphasize the role of MRI as a non-invasive method for performing a comprehensive and integrated assessment of musculoskeletal health in the growing skeleton.

Automated summary

This study investigates the role of 3T-MRI in assessing musculoskeletal health in children and young people. The results provide insights into the relationships between bone, muscle, and bone marrow, and highlight the importance of MRI as a non-invasive method for comprehensive evaluation of musculoskeletal health in growing individuals.