Citations 1
McArdle sign and neck flexion-induced change in central motor conduction in multiple sclerosis
Hoffman, E. Matthew , Brown, Lucille, Jolliffe, Evan, Sechi, Elia , Harmsen, William S. , Schilaty, Nathan D. , Weinshenker, Brian G. , Weinshenker, Brian G , Schilaty, Nathan D , Sechi, Elia
Multiple Sclerosis Journal | November 6, 2024 | Volume: 30 | Issue: 14 | Pages: 1830-1834
Background: Rapidly reversible weakness with neck flexion (McArdle sign) is common in patients with multiple sclerosis (MS). The pathophysiology is unknown. Objective: To evaluate changes in central motor conduction time (CMCT) in patients with and without McArdle sign. Methods: We measured McArdle sign with a torque cell and CMCT with neck flexed and extended in patients with MS, other causes of myelopathy, and healthy controls. Results: CMCT was prolonged with neck flexion disproportionately in those with MS-associated myelopathy (MSAM) with prominent McArdle sign compared to MS patients with lesser degrees of McArdle sign, and to controls. Conclusion: McArdle sign may result from stretch-induced slowing of conduction due to demyelination.