Establishment, behavioral, structural and functional characterization of a hindlimb amputation model in mice with multimodal MRI and MRS

Motivation: Limb amputation frequently leads to pain in residual limb and phantom sensations, but there is no comprehensively described mouse model for translational research. Goal(s): To extensively phenotype a mouse model of limb amputation to investigate contributing factors of pain. Approach: Behavioral characterization and multimodal in vivo brain imaging (Voxel-based Morphometry, resting-state functional Magnetic Resonance Imaging and MR-spectroscopy). Results: VBM showed reduction in primary somatosensory and visual areas (ipsilateral-hemisphere). Functional analysis showed potential neurocompensatory mechanisms and reorganization (left hemisphere). Metabolic data indicated reduced glutamate in the left somatosensory area, and increased N-acetylaspartate in the right somatosensory area. Impact: We phenotyped a mouse model of limb amputation and showed that sensory and motor areas are involved in the manifestation of pain, which strengthens previous evidence and guides future research.