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Updated: Jul 11, 2026
09:34
Use of In Vivo Single-fiber Recording and Intact Dorsal Root Ganglion with Attached Sciatic Nerve to Examine the Mechanism of Conduction Failure
Published on: August 27, 2019
Neuropathies associated with conduction block
1Wayne State University School of Medicine, Department of Neurology, Detroit, Michigan 48201, USA. Ralewis@med.wayne.edu
Current Opinion in Neurology
|September 22, 2007
Summary
Lewis-Sumner syndrome and multifocal motor neuropathy are distinct neurological disorders defined by conduction block. Recent findings clarify their differences, crucial for accurate diagnosis and treatment.
Area of Science:
- Neurology
- Neurophysiology
Background:
- Lewis-Sumner syndrome (LSS) and multifocal motor neuropathy (MMN) are often confused due to shared feature of conduction block.
- Understanding the pathophysiology of conduction block is key to differentiating these conditions.
Purpose of the Study:
- To re-evaluate Lewis-Sumner syndrome and multifocal motor neuropathy.
- To clarify the distinctions between LSS and MMN based on current understanding of conduction block.
Main Methods:
- Review of current literature on LSS and MMN.
- Analysis of pathophysiology of conduction block, including node of Ranvier structure.
- Evaluation of axonal excitability studies.
- Comparison of diagnostic criteria for conduction block.
Main Results:
- Conduction block understanding has advanced with insights into the node of Ranvier.
- Axonal excitability studies suggest MMN affects only motor nerves.
- Published criteria for conduction block vary in accuracy; electromyographers must be cautious.
- LSS appears to be a multifocal variant of chronic inflammatory demyelinating polyneuropathy (CIDP), while MMN is distinct.
Conclusions:
- Recognizing distinctions between LSS and MMN is vital for appropriate therapy.
- Further understanding of these conditions requires careful consideration of their overlaps and differences.
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