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Updated: Jun 4, 2026
06:35
In Vivo Electrophysiological Measurement of Compound Muscle Action Potential from the Forelimbs in Mouse Models of Motor Neuron Degeneration
Published on: June 15, 2018
Monomelic amyotrophy is not always benign: a case report
Cristina Moglia1, Andrea Calvo, Stefania Cammarosano
1ALS Centre, Department of Neuroscience, University of Turin, San Giovanni Hospital, Torino, Italy.
Summary
Monomelic amyotrophy (MA), a rare motor neuron disease variant, can progress to widespread, fatal disease. This case highlights MA
Area of Science:
- Neurology
- Neuron science
- Clinical neurology
Background:
- Monomelic amyotrophy (MA) is a rare variant of motor neuron disease (MND).
- MA is characterized by muscle weakness and atrophy localized to a single limb.
Observation:
- A 56-year-old Italian patient presented with segmental muscular atrophy limited to the lower left limb.
- The patient remained clinically stable for 11 years.
- Subsequently, the disease progressed to affect all limbs, bulbar, and respiratory muscles.
Findings:
- The patient died from respiratory failure 15 years after disease onset.
- This case demonstrates rare progression of MA to diffuse, fatal MND.
- Progression occurred even after a prolonged period of clinical stability.
Implications:
- Monomelic amyotrophy may represent a distinct clinical presentation within the broader spectrum of motor neuron disease.
- MA can evolve into a more severe, generalized form of MND.
- Findings support the concept of MA being part of the clinical continuum of MND.
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