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

The Scratch Collapse Test (SCT) is a neurocutaneous reflex used to detect peripheral nerve compression in nerve tunnel syndromes. It first involves applying a sensory stimulus to the skin over the suspected nerve compression point, then bilaterally testing the strength of a specific muscle in the patient. Compression is then manifested by a transient loss of strength in the muscle on the affected side, while it is preserved on the healthy side. This loss of strength is transient and disappears after a few seconds. This test can be performed during a patient's clinical examination, with the physician assessing strength or, conversely, muscle collapse. However, while several articles have described the relevance of this test, as well as its sensitivity and specificity, no study has specifically investigated and measured this observed loss of eccentric muscle tone and its unilateral and transient nature, even though the phenomenon of CSP (cutaneous silent period) has been described.

We therefore propose to analyze the myographic tracing obtained in patients diagnosed with unilateral carpal tunnel syndrome. A transient loss of muscle tone is expected by selective needle myography on the pathological side after cutaneous sensory stimulation of the wrist, while cutaneous sensory stimulation on the healthy side does not alter the tracings obtained by myography.

Study Overview

• Status: Recruiting
• Conditions: Carpal Tunnel Syndrome (CTS)
• Intervention / Treatment: Procedure: electromyograph; Diagnostic test: Scratch Collapse Test

• Study Type: Interventional
• Enrollment (Estimated): 25
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Vincent Martinel, Dr; Phone Number: 0033562563895; Email: drvmartinel@goop65.fr

Study Locations

• France
  • Tarbes, France, 65000
    • Recruiting
    • Clinique de l'Ormeau
    • Contact: Vincent Marinel, Dr; Phone Number: 0033562563898; Email: drvmartinel@goop65.fr

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Patient with unilateral carpal tunnel syndrome; Patient with clinical unilateral carpal tunnel syndrome diagnosed by history, clinical examination and electromyography,

Procedure: electromyograph; This examination uses electrodes placed along the path of the median nerve to measure the transmission of nerve impulses (conduction studies). It is performed on both hands to compare the results.; Diagnostic test: Scratch Collapse Test; The Scratch Collapse Test (SCT) is a neurocutaneous reflex used to detect peripheral nerve compression in nerve canal syndromes. It involves first performing a sensory stimulus on the skin at the suspected nerve compression site, then bilaterally testing the strength of a specific muscle in the patient. Compression is then manifested by a transient loss of strength in the muscle on the affected side, while it is preserved on the stimulated side.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Evolution of the myographic tracings	Evolution of the myographic tracings (of the infraspinatus muscle) of the pathological arm immediately after ipsilateral stimuli compared to the basic tracings (before stimuli) of the pathological arm and evolution of the myographic tracings of the pathological arm 20 seconds after ipsilateral stimuli compared to the basic tracings (before stimuli) of the pathological arm.	one day

Collaborators and Investigators

• Sponsor: Elsan

Study record dates

Study Major Dates

• Study Start (Actual): November 4, 2025
• Primary Completion (Estimated): May 4, 2026
• Study Completion (Estimated): May 5, 2026

Study Registration Dates

• First Submitted: November 17, 2025
• First Submitted That Met QC Criteria: November 21, 2025
• First Posted (Actual): November 25, 2025

Study Record Updates

• Last Update Posted (Actual): November 25, 2025
• Last Update Submitted That Met QC Criteria: November 21, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Nervous System Diseases; Wounds and Injuries; Neuromuscular Diseases; Peripheral Nervous System Diseases; Median Neuropathy; Mononeuropathies; Nerve Compression Syndromes; Cumulative Trauma Disorders; Sprains and Strains; Carpal Tunnel Syndrome
• Other Study ID Numbers: SC-My; 2025-A01019-40 (Other Identifier: ID-RCB)

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No