Pathological findings at the site of conduction block in multifocal motor neuropathy

Ann Neurol. 1993 Feb;33(2):152-8. doi: 10.1002/ana.410330204.


We report on 2 patients with multifocal motor neuropathy with focal conduction block involving motor but not sensory fibers at the site of nerve swelling. A nerve biopsy specimen from adjacent to the enlargement in 1 patient showed a perivascular area containing scattered demyelinated axons surrounded by small onion bulbs. The observed pathological findings are consistent with the conduction block considered characteristic of this neuropathy, although the underlying immunological mechanisms for selectivity and persistence remain undetermined.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials
  • Adult
  • Axons / ultrastructure
  • Electrophysiology
  • Fingers / innervation
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Monitoring, Intraoperative
  • Motor Activity / physiology
  • Motor Neuron Disease / diagnosis
  • Motor Neuron Disease / pathology*
  • Motor Neuron Disease / physiopathology
  • Myelin Sheath / ultrastructure
  • Nervous System / physiopathology
  • Neural Conduction*
  • Sensation / physiology
  • Thumb / innervation