A loss of functional spinal alpha motor neurons in amyotrophic lateral sclerosis.
We obtained motor unit number estimates (MUNEs) of the hypothenar and the extensor digitorum brevis muscles in ALS patients by our new technique. One year after symptom onset, the MUNEs had decreased to +/-30% of normal. Accordingly, we suggest that 70% of functional spinal alpha motor neurons are lost in the first post-onset year in ALS.
Arasaki
K
K
Department of Neurology, NTT Kanto Teishin Hospital, Tokyo, Japan.
Tamaki
M
M
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000690:Amyotrophic Lateral Sclerosis / Q000473:pathology*; D016022:Case-Control Studies; D006801:Humans; D008875:Middle Aged; D009046:Motor Neurons / Q000502:physiology*; D015203:Reproducibility of Results; D013116:Spinal Cord / Q000166:cytology*