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Updated: Jun 22, 2026
05:57
A Rapid Automated Protocol for Muscle Fiber Population Analysis in Rat Muscle Cross Sections Using Myosin Heavy Chain Immunohistochemistry
Published on: March 28, 2017
Changes in muscle fiber density following a stroke.
M Lukács1, L Vécsei, S Beniczky
1Department of Neurology, Miskolc Health Center, Miskolc, Hungary. mikluk33@hotmail.com
Summary
Following a stroke, motor unit reorganization occurs, with increased fiber density in paretic muscles. This muscle reinnervation process is linked to stroke severity and happens early after the event.
Area of Science:
- Neuroscience
- Neurology
- Rehabilitation Medicine
Background:
- Upper motor neuron lesions, common after stroke, lead to functional loss in large motor units.
- Understanding motor unit reorganization is crucial for stroke recovery and rehabilitation.
Purpose of the Study:
- To investigate the degree and time course of motor unit reorganization after stroke.
- To correlate changes in motor units with stroke severity and clinical signs.
Main Methods:
- Single-fiber electromyography (SFEMG) was used to measure fiber density (FD) in the abductor digiti minimi muscle.
- 59 ischemic stroke patients (hemiparesis duration: 2 weeks to 48 months) and 42 healthy controls were examined.
- FD was compared between hemiparetic, unaffected sides, and controls.
Main Results:
- Fiber density (FD) was significantly increased in the hemiparetic muscles compared to the unaffected side and controls.
- The increase in FD correlated with the severity of clinical symptoms.
- FD increased within the first 10 months post-stroke, then stabilized.
Conclusions:
- Muscle reinnervation begins in the acute phase after stroke.
- The observed changes in motor units are associated with symptom severity.
- Findings suggest early trans-synaptic degeneration of spinal motor neurons post-upper motor neuron lesion.
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