Associations of Vertebral Marrow Multiparametric MRI Measurements With Lumbar Degeneration.

BACKGROUND

Vertebral marrow alterations are associated with lumbar spine degeneration, but their relationships with marrow fat and diffusion measurements remain unclear.

PURPOSE: To assess associations of vertebral marrow proton density fat fraction (PDFF), apparent diffusion coefficient (ADC), slow diffusion coefficient (SDC), and diffusion-derived vessel density (DDVD) with lumbar structural degeneration and low back pain.

STUDY TYPE: Prospective cross-sectional study.

POPULATION: One hundred and sixty-two community-dwelling adults (male/female: 71/91, age: 55.1 ± 11.1 years, and body mass index (BMI): 24.4 ± 3.3 kg/m2).

FIELD STRENGTH/SEQUENCE: 3.0-T; sagittal multi-b-value readout-segmented echo-planar DWI and transverse six-echo three-dimensional q-Dixon imaging.

ASSESSMENT: PDFF, ADC, SDC, and DDVD were measured adjacent to the L3/4-L5/S1 endplates. Six structural features were independently evaluated by two radiologists with 8 and 7 years of experience and summed across levels as a degenerative burden score (range, 0-18). Chronic low back pain was self-reported pain lasting at least 3 months.

STATISTICAL TESTS: Generalized estimating equations, multivariable linear and logistic regression, principal component analysis, and K-means clustering. p < 0.05 and FDR-adjusted q < 0.05 were considered statistically significant.

RESULTS

After FDR correction, ADC was associated with Modic changes (OR = 1.520), endplate defects (OR = 2.072), and nerve root compression (OR = 1.641), while PDFF was associated with central canal stenosis (OR = 2.152). Age (standardized regression coefficient (β) = 0.534) and BMI (β = 0.200), but not ADC (β = 0.182, q = 0.123), were associated with degenerative burden. No MRI parameter was associated with low back pain after FDR correction (q = 0.312-0.975). Three exploratory clusters differed in age and sex, but not adjusted degenerative burden (nominal p = 0.381).

DATA

CONCLUSION

ADC showed the most consistent adjusted associations with lumbar structural degeneration. The clinical significance of the identified vertebral marrow imaging profiles remains uncertain.

EVIDENCE LEVEL: 3.

TECHNICAL EFFICACY: Stage 2.