Hereditary Motor and Sensory Neuropathy involves anterior horn cell, spinal roots, posterior root ganglion, and peroneal nerves.
By this time, there were a few studies about the anterior horn cell involvement which were autopsy findings and EMG findings which showed large motor units.
We stimulated motor cortex and recorded from abductor digiti quinti muscle individually and found prolonged latency and decreased amplitude of motor evoked potentials, We concluded these finding were due to anterior horn cell involvement.