Muscle response collapse during the Scratch Collapse Test for carpal tunnel syndrome

Pilot Study, Aimed at Describing in Myography, the Collapse of the Muscular Response Visualized in the Scratch Collapse Test, in Carpal Tunnel Syndrome

Not applicable Interventional Elsan · NCT07248124

We will try to measure the brief, one-sided loss of muscle strength seen during the Scratch Collapse Test in adults with unilateral carpal tunnel syndrome.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment25 (estimated)
Ages18 Years and up
SexAll
SponsorElsan Academic / other
Locations1 site (Tarbes)
Trial IDNCT07248124 on ClinicalTrials.gov

What this trial studies

This pilot interventional project uses electromyography (EMG) to record muscle responses while performing the Scratch Collapse Test in adults with clinically and electrically confirmed unilateral carpal tunnel syndrome. Investigators will apply a sensory stimulus over the suspected compression point and record bilateral muscle strength and EMG signals to characterize the transient loss of eccentric muscle tone on the affected side. The protocol excludes people with other neuropathies, diabetes, cervical pathology, or other conditions that could confound nerve conduction or muscle response. The aim is to provide objective, time-resolved measurements of the phenomenon that has previously been described clinically but not quantified with EMG.

Who should consider this trial

Good fit: Adults over 18 with unilateral carpal tunnel syndrome confirmed by history, exam, and electromyography who can give informed consent and are covered by a social security scheme.

Not a fit: People with bilateral disease, diabetic or other peripheral neuropathy, associated cervical or other nerve pathology, pregnancy, cognitive impairment, or those unable/unwilling to undergo EMG are unlikely to benefit from this protocol.

Why it matters

Potential benefit: If successful, this could make the Scratch Collapse Test more objective and help clinicians detect and document carpal tunnel nerve compression more reliably.

How similar studies have performed: Clinical reports have described the Scratch Collapse Test's sensitivity and specificity and the cutaneous silent period is a known phenomenon, but no prior study has directly measured the transient unilateral loss of eccentric muscle tone with EMG, making this approach relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Patient over 18 years old
* Patient with clinical unilateral carpal tunnel syndrome diagnosed by history, clinical examination and electromyography,
* Patient who has been informed and has given their free, informed, and written consent,
* Patient affiliated with or beneficiary of a social security scheme.

Exclusion Criteria:

* Other associated canal syndrome on either side (ulnar, defilement, lacertus),

  * Rotator cuff pathology, insufficiency or rupture of the infraspinatus,
  * Associated cervical pathology,
  * Neuropathy, central or peripheral neurological disease,
  * Diabetic patient,
  * Patient with cognitive impairments that prevent the understanding of the study information,
  * Refusal to participate in the study,
  * Pregnant, parturient, or breastfeeding woman,
  * Patient under legal protection,
  * Patient not receiving health protection,
  * Protected patient: adult under guardianship, curatorship, or other legal protection, deprived of liberty by judicial or administrative decision

Where this trial is running

Tarbes

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Carpal Tunnel Syndrome
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.