Traumatic spinal cord injury (SCI) has been shown to trigger structural atrophic changes within the spinal cord and brain. However, the relationship between structural changes and magnitude of neuropathic pain (NP) remains incompletely understood. Voxel-wise analysis of anatomical magnetic resonance imaging data provided information on cross-sectional cervical cord area and volumetric brain changes in 30 individuals with chronic traumatic SCI and 31 healthy controls. Participants were clinically assessed including neurological examination and pain questionnaire. Compared to controls, individuals with SCI exhibited decreased cord area, reduced grey matter (GM) volumes in anterior cingulate cortex (ACC), left insula, left secondary somatosensory cortex, bilateral thalamus, and decreased white matter volumes in pyramids and left internal capsule. The presence of NP was related with smaller cord area, increased GM in left ACC and right M1, and decreased GM in right primary somatosensory cortex and thalamus. Greater GM volume in M1 was associated with amount of NP. Below-level NP-associated structural changes in the spinal cord and brain can be discerned from trauma-induced consequences of SCI. The directionality of these relationships reveals specific changes across the neuroaxis (i.e., atrophic changes versus increases in volume) and may provide substrates of underlying neural mechanisms in the development of NP.

In this prospective study, we made an unbiased voxel-based analysis to investigate above-stenosis spinal degeneration and its relation to impairment in patients with cervical spondylotic myelopathy (CSM). Twenty patients and 18 controls were assessed with high-resolution MRI protocols above the level of stenosis. Cross-sectional areas of grey matter (GM), white matter (WM), and posterior columns (PC) were measured to determine atrophy. Diffusion indices assessed tract-specific integrity of PC and lateral corticospinal tracts (CST). Regression analysis was used to reveal relationships between MRI measures and clinical impairment. Patients showed mainly sensory impairment. Atrophy was prominent within the cervical WM (13.9%, p = 0.004), GM (7.2%, p = 0.043), and PC (16.1%, p = 0.005). Fractional anisotropy (FA) was reduced in the PC (-11.98%, p = 0.006) and lateral CST (-12.96%, p = 0.014). In addition, radial (+28.47%, p = 0.014), axial (+14.72%, p = 0.005), and mean (+16.50%, p = 0.001) diffusivities were increased in the PC. Light-touch score was associated with atrophy (R(2) = 0.3559, p = 0.020) and FA (z score 3.74, p = 0.003) in the PC, as was functional independence and FA in the lateral CST (z score 3.68, p = 0.020). This study demonstrates voxel-based degeneration far above the stenosis at a level not directly affected by the compression and provides unbiased readouts of tract-specific changes that relate to impairment.