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Updated: Jul 18, 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
Multifocal motor neuropathy with conduction block: slow but not benign
Dale J Lange1, Louis H Weimer, Werner Trojaborg
1Department of Neurology, Mt Sinai School of Medicine, New York, NY 10029, USA. dale.lange@mssm.edu
Archives of Neurology
|December 19, 2006
Summary
Multifocal motor neuropathy with conduction block can slowly progress and lead to permanent nerve damage, even without treatment. This case highlights the potential for nerve inexcitability and axonal loss over time.
Area of Science:
- Neurology
- Neurophysiology
Background:
- Multifocal motor neuropathy with conduction block (MMN) is a rare autoimmune disorder affecting peripheral nerves.
- Early diagnosis and treatment are crucial for managing MMN and preventing disability.
Observation:
- A case report detailing an 18-year observation of a patient with MMN who opted against treatment.
- The patient experienced progressive weakness and muscle wasting, particularly in the arms.
- Clinical and physiological assessments revealed evolving nerve conduction abnormalities.
Findings:
- The patient developed significant weakness in 20 muscles over 18 years.
- Nerves initially showing conduction block became inexcitable, indicating axonal damage.
- Axonal changes, evidenced by reduced compound muscle action potential amplitude, were observed in multiple nerves.
Implications:
- MMN can have a slowly progressive but ultimately disabling course.
- Conduction block in MMN may precede irreversible axonal loss.
- The need for improved diagnostic markers and therapeutic strategies for MMN is emphasized.
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