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Alterations in Muscle Tone ll

Alterations in Muscle Tone ll

Alterations in muscle tone are common manifestations of neurological disorders and reflect dysfunction within different nervous system regions. Spasticity, paratonia, and dystonia represent distinct forms of hypertonia, each with unique mechanisms, clinical features, and diagnostic importance.CharacteristicsSpasticity happens from upper motor neuron lesions and is characterized by velocity-dependent resistance to passive movement. Clinical features include:Exaggerated deep tendon reflexesClonus...

Spasmolytic Agents: Chemical Classification

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Wave summation
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Related Experiment Video

Updated: May 11, 2026

Methods to Quantify Pharmacologically Induced Alterations in Motor Function in Human Incomplete SCI

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.

American Journal of Physical Medicine & Rehabilitation

|April 27, 2013

Summary

Physiologic and psychologic triggers can influence spasticity. Objective measures confirm triggers like pregnancy and cold, while self-reports suggest stress and clothing tightness also increase spasticity.

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Methods to Quantify Pharmacologically Induced Alterations in Motor Function in Human Incomplete SCI

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Repeated Transcranial Magnetic Stimulation Combined with Action Observation Training in Children with Spastic Cerebral Palsy

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Area of Science:

Neurology
Rehabilitation Medicine

Background:

Spasticity is a common symptom in neurological disorders.
Identifying triggers is crucial for managing spasticity.

Purpose of the Study:

To systematically review literature on physiologic and psychologic triggers of spasticity.
To evaluate the evidence supporting various spasticity triggers.

Main Methods:

Literature search of PubMed, EMBASE, CINAHL, and PEDro databases.
Inclusion of studies using clinical tests or self-reports for spasticity assessment.
Review of 24 relevant articles from 1152 initially scanned.

Main Results:

Objective clinical tests confirmed increased spasticity with pregnancy, posture, cold, circadian rhythm, and skin conditions.
Self-reports indicated bowel/bladder issues, menstrual cycle, stress, and tight clothing as potential triggers.
No evidence found linking heterotopic ossification, hemorrhoids, DVT, fever, or sleep patterns to increased spasticity.

Conclusions:

Self-reported triggers suggest significant spasticity increases, but objective evidence is often lacking.
The effects of many triggers remain inconclusive without objective validation.
Findings primarily from spinal cord injury population; generalizability to other neurological conditions is unknown.