Association Between Motor Pathway Damage and Motor Deficit in Upper and Lower Limb in People With MS

Area of Science:

• Neuroscience
• Neurology
• Radiology

Background:

• Corticospinal tract (CST) damage is prevalent in multiple sclerosis (MS), but clinical symptom severity varies.
• Understanding the relationship between CST lesion extent/severity and motor impairment is crucial for MS patient management.

Purpose of the Study:

• To investigate the association between corticospinal tract lesion load and microstructural damage with motor deficits in MS patients.
• To compare CST damage in MS patients with isolated hyperreflexia, lower limb deficits, and deficits in both upper and lower limbs.

Main Methods:

• A prospective cross-sectional study included 100 people with MS.
• Corticospinal tract lesions were segmented using 3D FLAIR, T2*, and T2-weighted imaging.
• Quantitative T1 MP2RAGE assessed microstructural damage severity in the brain and cervical spinal cord CST.

Main Results:

• Ninety-two MS patients were analyzed across three groups: isolated hyperreflexia (A), lower limb deficits (B), and upper/lower limb deficits (C).
• Groups B and C exhibited significantly higher CST lesion volumes in the brainstem and cervical spinal cord compared to group A (p < 0.001).
• Quantitative T1 was elevated in the cervical CST for groups B and C compared to A (p < 0.05), with age, disease duration, brainstem lesion volume, and cervical CST quantitative T1 differentiating group A from B/C.

Conclusions:

• Motor deficits in people with MS are associated with CST damage in the brainstem and cervical spinal cord.
• The study could not establish significant differences in CST damage between MS patients with lower limb deficits versus those with deficits in both upper and lower limbs.