Can Magnetic Resonance Imaging Reveal Lower Motor Neuron Damage after Traumatic Spinal Cord Injury? A Scoping Review

Voluntary muscle movement relies on a pathway from the brain down the spinal cord. Spinal cord injuries (SCIs) often damage upper motor neuron (UMN) pathways, but can also damage lower motor neurons (LMNs). Identifying LMN damage is crucial for emerging treatments like nerve transfer surgery, which can restore function if LMNs are intact. Current diagnostic methods have limitations, prompting the search for MRI biomarkers to detect LMN damage early. This review explores the potential of MRI to identify LMN damage in SCI patients, highlighting the need for further research in this area to improve treatment strategies and functional outcomes.

• 1
  The review identified a significant gap in the literature regarding the use of MRI biomarkers to detect LMN damage in the acute phase after SCI.
• 2
  Two small studies were found: one showing MRI evidence of damage in the anterior cervical spinal cord of SCI patients with low motor unit counts, and another demonstrating a correlation between spinal cord discontinuity length on MRI and denervated intercostal segments.
• 3
  The discussion explores the potential of conventional and quantitative MRI techniques, such as DTI, to identify LMN damage by assessing hemorrhage, edema, swelling, compression, and microstructural tissue integrity.