[Multivariate analysis of spinal automatism in neurological diseases]

We investigated the relationship between spinal automatism (SA) and other neurological signs and symptoms (pyramidal, extrapyramidal, cerebellar, autonomic) by multivariate analysis in cervical spondylotic myelopathy (CSM) 112 cases, amyotrophic lateral sclerosis (ALS) 121 cases, and multiple system atrophy (MSA) 115 cases (olivo-ponto-cerebellar atrophy (OPCA) 55 cases, Shy-Drager syndrome (SDS) 42 cases, striato-nigral degeneration (SND) 18 cases). SA elicitation maneuver we used was pinprick stimulation at the dorsal pedal skin, and all cases showed twitched or phasic triple flexion pattern. As SA was elicited in 19 cases in CSM (17.0%), 23 cases (19.0%) in ALS, 36 cases (31.3%) in MSA, SA was more elicited in MSA than in ALS and CSM (p < 0.05, p < 0.01 by chi-squared test). In MSA, SA tended to be elicited more likely in SDS (21 cases, 50.0%) and in SND (8 cases, 44.4%) than in OPCA (7 cases, 12.7%) (p < 0.01 by chi-squared test). In MSA, the longer the duration of the disease became, the more SA was elicited, but not in ALS and CSM. Multivariate analysis (quantification method type II) showed that clinical signs as a statistical contribution factor for SA elicitation ranked Babinski's sign, micturition disturbance in ALS and CSM and Babinski's sign, orthostatic hypotension in MSA in order: In all 3 diseases, Babinski's sign and autonomic disturbance ranked higher. This conclusion suggested that SA was not always related to the pyramidal tract damage and was associated with the damage of small myelinated fibers in and/or around the pyramidal tract.