Stroke and Assessment of Muscle Tone

Study Overview
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Brief Summary
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Spasticity is defined as a state of increased muscle tone, which evokes an increased resistance to a passive and fast stretching of the muscle. Indeed, the degree of spasticity depends, among other things, on the stretching velocity performed to the muscle. However, most of the tools used in the clinical setting to assess spasticity do not take into account the relationship between increased muscle tone and speed of stretching. Instead of that, muscle tone is usually assessed in a relaxed position of the muscle. Likewise, to date, despite the functional disabilities related to the presence of chronic pain after a stroke, no previous study has correlated muscle tone and pressure pain sensitivity within this population

Official Title
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Stroke and Myotonometer: Validity, Reliability and Discrimination Between the Mechanical and Sensory Component of Spasticity

Conditions
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Stroke, Muscle Tone Abnormalities, Pain, Muscle Spasticity

Intervention / Treatment
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* Diagnostic Test: Assessment of Tone, Pain and Thickness


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Be older than 18 years Clinical diagnosis of stroke, confirmed using a MRI. No previous history of other strokes. Increases muscle tone in upper and lower extremities (punctuation equal to or superior to 1 in the Tardieu Scale, Ashworth Scale) Ability to understand the study goals, follow simple instructions and provide informed consent. Score equal to or superior to 24 in the Minimental State Examination. Exclusion Criteria: Any other confirmed neurological disorder that may influence muscle tone (multiple sclerosis, Parkinson, muscle dystrophies...) A chronic musculoskeletal disorder in the upper or lower limb. Previous history of surgery in the upper or lower extremities. Changes in the medication intake that may affect muscle tone assessments in the 48 hours before data collection. Having received botulin toxin in gastrocnemius or biceps brachii muscles in the 30 days before data collection. A concomitant acute infection during data collection. A previous epileptic crisis in the week before the study or during the study.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Control Group<br>A control group of healthy subjects with no previous history of neurological disorders or conditions. This group pf participants will be selected in a similar population based-cohort than the other two study groups. | Diagnostic Test: Assessment of Tone, Pain and Thickness<br>* Evaluation of Muscle state of tension, self-reported response to mechanical pressure pain and muscle thickness. The evaluation process of muscle tone and pressure pain sensitivity will be carried out following a topographical mapping covering myotendinous and muscle belly sites in the biceps brachii and the gastrocnemius muscles<br>|
| Acute Stroke Group<br>In this group, participants who suffered a previous stroke within 3 months before data collection will be included. | Diagnostic Test: Assessment of Tone, Pain and Thickness<br>* Evaluation of Muscle state of tension, self-reported response to mechanical pressure pain and muscle thickness. The evaluation process of muscle tone and pressure pain sensitivity will be carried out following a topographical mapping covering myotendinous and muscle belly sites in the biceps brachii and the gastrocnemius muscles<br>|
| Chronic Stroke Group<br>In this group, only participants who have suffered a previous stroke of more than 3 months duration before data collection will be included. | Diagnostic Test: Assessment of Tone, Pain and Thickness<br>* Evaluation of Muscle state of tension, self-reported response to mechanical pressure pain and muscle thickness. The evaluation process of muscle tone and pressure pain sensitivity will be carried out following a topographical mapping covering myotendinous and muscle belly sites in the biceps brachii and the gastrocnemius muscles<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pressure Pain Threshold, assessed by Manual Pressure Algometry | A handheld electronic pressure algometer with a 1-cm2 contact probe will be used. Pressure pain thresholds (PPTs), as the minimum necessary pressure force to evoke pain, will be assessed bilaterally over biceps brachii and the gastrocnemius muscles (medial and lateral). Assessments will be made using a topographical mapping covering myotendinous and muscle belly sites in the above mentioned muscles. A 30-second break will be used between assessments to prevent bruising, and an average of the two measures over each site will be calculated for the statistical analysis. Pressure algometry is reliable in healthy individuals, and in stroke patients | One time assessment | 
| Muscle Tone Assessment, using the modified Tardieu Scale | The modified Tardieu Scale is the most common tool used in the clinical setting to evaluate the muscle tone. The muscle response to a slow and fast stretching will be performed. During the fast stretching, the joint angle in which the muscle responds with difficulty will be collected using an electrogoniometer. | One time assessment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Muscle Stiffness, assessed by a myotonometer | The stiffness of the biceps brachii and gastrocnemius muscles will be collected using a handheld myotonometer device, the so-called MyotonPRO, (Myoton AS, Estonia). The MyotonPRO is small, non-invasive, and it has shown good validity and high reliability in larger and smaller body muscles. This device delivers a multi-scan mode of three brief mechanical impulses, each one shortly followed by a quick release, to record the damped natural oscillation of the muscle using an accelerometer. Evaluations will be made in the affected and non-affected sides of stroke patients and in dominant and non-dominant sides of control participants. | One time assessment | 
| Muscle State of Tension (Muscle Tone), assessed by a myotonometer | The tone of the biceps brachii and gastrocnemius muscles will be collected using a handheld myotonometer device, the MyotonPRO, (Myoton AS, Estonia). The MyotonPRO is small, non-invasive, and it has shown good validity and high reliability in larger and smaller body muscles. This device delivers a multi-scan mode of three brief mechanical impulses, each one shortly followed by a quick release, to record the damped natural oscillation of the muscle using an accelerometer. Evaluations will be made in the affected and non-affected sides of stroke patients and in dominant and non-dominant sides of control participants. | One time assessment | 
| Muscle Thickness | The thickness of the assessed muscles will be evaluated using ecography. Muscle thickness will be assessed in one point corresponding to a myotendinous site and one point corresponding to a muscle belly location in both, the biceps brachii and gastrocnemius muscles. Evaluations will be made in the affected and non-affected sides of stroke patients and in dominant and non-dominant sides of control participants. | One time assessment | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Topographical mapping, Muscle state of tension, Myotonometer, Pressure Pain Threshold, Muscle Thickness