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Updated: Jul 20, 2026

Assessing Rat Diaphragm Motor Unit Connectivity Outcome Measures as Quantitative Biomarkers of Phrenic Motor Neuron Degeneration and Compensation
Published on: April 19, 2024
Motor unit number estimates correlate with strength in polio survivors
Eric J Sorenson1, Jasper R Daube, Anthony J Windebank
1Department of Neurology, Mayo Clinic, Rochester, Minnesota 55905, USA. sorenson.eric@mayo.edu
Abstract:
Motor unit number estimation (MUNE) has been proposed as an outcome measure in clinical trials for the motor neuron diseases. One major criticism of MUNE is that it may not represent a clinically meaningful endpoint. We prospectively studied a cohort of polio survivors over a period of 15 years with respect to MUNE and strength. We identified a significant association between thenar MUNE and arm strength, extensor digitorum brevis MUNE and leg strength, and the summated MUNE and global strength of the polio survivors. These findings confirm the clinical relevance of MUNE as an outcome measure in the motor neuron diseases and provide further validation for its use in clinical trial research.
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