Cervical Spinal Cord Atrophy Profile in Adult SMN1-Linked SMA
Overview
Authors
Affiliations
Purpose: The mechanisms underlying the topography of motor deficits in spinal muscular atrophy (SMA) remain unknown. We investigated the profile of spinal cord atrophy (SCA) in SMN1-linked SMA, and its correlation with the topography of muscle weakness.
Materials And Methods: Eighteen SMN1-linked SMA patients type III/V and 18 age/gender-matched healthy volunteers were included. Patients were scored on manual muscle testing and functional scales. Spinal cord was imaged using 3T MRI system. Radial distance (RD) and cord cross-sectional area (CSA) measurements in SMA patients were compared to those in controls and correlated with strength and disability scores.
Results: CSA measurements revealed a significant cord atrophy gradient mainly located between C3 and C6 vertebral levels with a SCA rate ranging from 5.4% to 23% in SMA patients compared to controls. RD was significantly lower in SMA patients compared to controls in the anterior-posterior direction with a maximum along C4 and C5 vertebral levels (p-values < 10-5). There were no correlations between atrophy measurements, strength and disability scores.
Conclusions: Spinal cord atrophy in adult SMN1-linked SMA predominates in the segments innervating the proximal muscles. Additional factors such as neuromuscular junction or intrinsic skeletal muscle defects may play a role in more complex mechanisms underlying weakness in these patients.
Spinal cord gray matter atrophy is associated with disability in spinal muscular atrophy.
Kesenheimer E, Wendebourg M, Weidensteiner C, Sander L, Weigel M, Haas T J Neurol. 2025; 272(1):102.
PMID: 39775109 PMC: 11706851. DOI: 10.1007/s00415-024-12740-3.
McKenna M, Kleinerova J, Power A, Garcia-Gallardo A, Tan E, Bede P Biology (Basel). 2024; 13(11).
PMID: 39596864 PMC: 11592215. DOI: 10.3390/biology13110909.
Brain magnetic resonance imaging of patients with spinal muscular atrophy type 2 and 3.
Stam M, Tan H, Schmidt R, van den Heuvel M, van den Berg L, Wadman R Neuroimage Clin. 2024; 44:103708.
PMID: 39577334 PMC: 11617753. DOI: 10.1016/j.nicl.2024.103708.
Role of circulating biomarkers in spinal muscular atrophy: insights from a new treatment era.
Giorgia Q, Gomez Garcia de la Banda M, Smeriglio P Front Neurol. 2023; 14:1226969.
PMID: 38020652 PMC: 10679720. DOI: 10.3389/fneur.2023.1226969.
Sari D, Biben V, Wiwaha G, Hilmanto D Eur J Med Res. 2023; 28(1):130.
PMID: 36941660 PMC: 10026388. DOI: 10.1186/s40001-023-01098-3.