Wrist MRI Trabecular Structure and Osteoporosis

OBJECTIVES: Early screening is necessary to prevent increasing osteoporosis and fragility fractures. Though Dual-energy X-ray absorptiometry (DEXA) defines osteoporosis, it does not predict fragility-fractures well. Trabecular structure as seen on MRI may be more sensitive and specific for osteoporosis and distal radius trabecular structure may identify changes earlier. We aimed to compare distal-radius trabecular structure as seen on MRI in patients with normal risk for fragility-fracture to those with increased risk of fragility-fracture. METHODS: Ten low-risk and 9 high-risk subjects underwent ultra- short-echo-time (UTE) MRI sequence scanning of an uninjured distal radius. Structural components included: trabecular plate-width, plate-rod ratio, plate volume fraction, rod volume fraction, trabecular thickness, pore size, pore size variation and trabecular density. A T-test or Mann-Whitney U test was conducted to determine differences in trabecular structure between low- and high-risk groups. Specificity and sensitivity were calculated to assess wrist MRI as a screening tool. RESULTS: There were statistically significant differences between low- and risk-risk groups for all parameters except trabecular thickness (p < 0.05). CONCLUSION: This study supports the feasibility of wrist MRI as a screening tool for early osteoporosis. This could potentially enable early prevention. Further study including longitudinal follow-up to determine the ability of this tool to predict fragility fractures is needed. ADVANCES IN KNOWLEDGE: We compared trabecular structure in wrist-MRI of high-risk and low-risk for fragility fracture, finding significant differences with optimal sensitivity/specificity to predict osteoporosis. Wrist MRI may offer early and effective screening for osteoporosis.