Axial loading during MRI reveals deviant characteristics within posterior IVD regions between low back pain patients and controls

• Purpose To investigate differences in functional intervertebral disk (IVD) characteristics between low back pain (LBP) patients and controls using T2-mapping with axial loading during MRI (alMRI). Methods In total, 120 IVDs in 24 LBP patients (mean age 39years, range 25-69) were examined with T2-mapping without loading of the spine (uMRI) and with alMRI (DynaWell((R)) loading device) and compared with 60 IVDs in 12 controls (mean age 38 years, range 25-63). The IVD T2-value was acquired after 20-min loading in five regions of interests (ROI), ROI1-5 from anterior to posterior. T2-values were compared between loading states and cohorts with adjustment for Pfirrmann grade. Results In LBP patients, mean T2-value of the entire IVD was 64 ms for uMRI and 66 ms for alMRI (p = 0.03) and, in controls, 65 ms and 65 ms (p = 0.5). Load-induced T2-differences (alMRI-uMRI) were seen in all ROIs in both patients (0.001>p<0.005) and controls (0.0001>p<0.03). In patients, alMRI induced an increase in T2-value for ROI1-3 (23%, 18% and 5%) and a decrease for ROI4 (3%) and ROI5 (24%). More pronounced load-induced decrease was detected in ROI4 in controls (9%/p=0.03), while a higher absolute T2-value was found for ROI5 during alMRI in patients (38 ms) compared to controls (33 ms) (p = 0.04). Conclusion The alMRI-induced differences in T2-value in ROI4 and ROI5 between patients and controls most probably indicate biomechanical impairment in the posterior IVD regions. Hence, alMRI combined with T2-mapping offers an objective and clinical feasible tool for biomechanical IVD characterization that may deepen the knowledge regarding how LBP is related to altered IVD matrix composition.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Annan klinisk medicin (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Other Clinical Medicine (hsv//eng)

Keyword

Intervertebral disk

T2-mapping

Low back pain

MRI

Axial loading during MRI

lumbar intervertebral disc

magnetic-resonance

annulus fibrosus

nucleus pulposus

water-content

3.0 tesla

degeneration

spine

feasibility

repair

Neurosciences & Neurology

Orthopedics

Publication and Content Type

ref (subject category)

art (subject category)