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Updated: May 11, 2026

Methods to Quantify Pharmacologically Induced Alterations in Motor Function in Human Incomplete SCI
Published on: April 18, 2011
Revisiting physiologic and psychologic triggers that increase spasticity
Chetan P Phadke1, Chitralakshmi K Balasubramanian, Farooq Ismail
1Upper Motorneuron Spasticity Research Program, West Park Healthcare Centre, Toronto, Canada.
Objective:
The aims of this study were to systematically identify and summarize the literature examining the impact of physiologic and psychologic triggers on spasticity and discuss the evidence supporting various types of triggers.
Design:
PubMed, EMBASE, CINAHL, and PEDro databases were searched using specific keyword combinations. Only studies using clinical tests or self-reports of spasticity were included.
Results:
A total of 1152 articles were scanned for relevance, and of 44 relevant articles, 24 were reviewed. Pregnancy, posture, cold, circadian rhythm, and skin conditions increased spasticity and were measured using objective clinical tests. Self-reports of spasticity suggest that triggers such as bowel- and bladder-related issues, menstrual cycle, mental stress, and tight clothing can all increase spasticity. No literature evidence of increase in spasticity in response to heterotopic ossification, hemorrhoids, deep vein thrombosis, fever, and sleep patterns was found.
Conclusions:
Although self-reports indicate a strong possibility of increasing spasticity, without objective examination, the true effects of these triggers on spasticity remain inconclusive. Most studies reviewed here were performed in the spinal cord injury population; therefore, it is not known whether these triggers induce similar effects in persons with other neurologic etiologies.
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