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Motor unit changes in thoracic paraspinal muscles in amyotrophic lateral sclerosis
Mamede de Carvalho1, Susana Pinto, Michael Swash
1Department of Neurology and Neurophysiology, Santa Maria Hospital, Lisbon, Portugal. mamedemg@mail.telepac.pt
Muscle & Nerve
|December 18, 2008
Summary
Motor unit potential (MUP) analysis in paraspinal muscles aids amyotrophic lateral sclerosis (ALS) diagnosis. Abnormalities in paraspinal muscles mirror those in limb muscles for ALS patients.
Area of Science:
- Neurology
- Electromyography
- Motor Neuron Diseases
Background:
- Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease affecting motor neurons.
- Electromyography, specifically motor unit potential (MUP) analysis, is crucial for diagnosing neuromuscular disorders.
- The utility of paraspinal muscle MUP analysis in ALS diagnosis requires further confirmation.
Purpose of the Study:
- To investigate the diagnostic value of paraspinal muscle motor unit potential (MUP) analysis in amyotrophic lateral sclerosis (ALS).
- To compare MUP abnormalities in paraspinal muscles (C-6, T-5) with limb muscles (biceps) in ALS patients.
Main Methods:
- Motor unit potential (MUP) analysis was conducted on 38 ALS patients and 28 controls.
- Electromyography was performed on C-6 and T-5 paraspinal muscles and biceps muscles.
- Analysis focused on MUP abnormalities, fasciculation potentials (FPs), and fibrillation potentials/positive sharp waves (fibs-sw).
Main Results:
- Similar MUP abnormalities were observed in paraspinal and limb muscles of ALS patients.
- Fasciculation potentials (FPs) were more prevalent in biceps muscles compared to paraspinal muscles.
- Fibrillation potentials and positive sharp waves (fibs-sw) showed equal frequency across all examined muscles.
Conclusions:
- Paraspinal muscle MUP analysis demonstrates significant abnormalities in ALS patients, comparable to limb muscles.
- These findings reinforce the diagnostic utility of analyzing paraspinal muscles in amyotrophic lateral sclerosis.
- Paraspinal MUP analysis is a valuable tool for the diagnosis of ALS.
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