Effect of Extracorporeal Shock Wave Therapy on Trapezius Muscle Stiffness (ESWT-Trapezius)

Effect of Extracorporeal Shock Wave Therapy on Trapezius Muscle Stiffness Assessed Using Shear-Wave Elastography

This study will examine whether extracorporeal shock wave therapy (ESWT) can reduce stiffness in the upper trapezius muscle. Muscle stiffness will be measured using a special ultrasound technique called shear-wave elastography (SWE), which allows researchers to assess changes in muscle properties. The aim of the study is to better understand if ESWT is effective in improving muscle function and reducing discomfort in this region. Healthy volunteers will be enrolled, and measurements will be taken before and after the ESWT treatment.

Study Overview

• Status: Completed
• Conditions: Muscle Stiffness
• Intervention / Treatment: Device: Extracorporeal Shock Wave Therapy

Detailed Description

This interventional study investigates the acute effects of extracorporeal shock wave therapy (ESWT) on the mechanical properties of the upper trapezius muscle, with a specific focus on muscle stiffness. Stiffness will be quantified using shear-wave elastography (SWE), a non-invasive ultrasound-based imaging modality that allows for real-time assessment of tissue elasticity.

Participants will undergo baseline SWE measurements of the upper trapezius muscle, followed by the application of a standardized ESWT protocol. Post-treatment measurements will be conducted immediately after the intervention to evaluate acute changes in stiffness. The primary objective is to determine whether a single session of ESWT induces measurable changes in muscle mechanical properties.

This study will contribute to the growing body of evidence regarding the physiological effects of ESWT on skeletal muscle tissue and its potential application in clinical and sports settings. Data collected will also support the development of future longitudinal studies assessing the therapeutic relevance of ESWT for myofascial dysfunction and musculoskeletal pain syndromes.

• Study Type: Interventional
• Enrollment (Actual): 40
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Slovenia
  • Municipality of Izola
    • Izola, Municipality of Izola, Slovenia, 6310
      • University of Primorska, Faculty of Health Sciences, Izola

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Age between 18 and 45 years
• Healthy individuals with no current musculoskeletal or neurological disorders
• No history of neck or shoulder surgery
• Willingness to abstain from vigorous upper-body exercise 24 hours prior to -measurements

Exclusion Criteria:

• Presence of neck or shoulder pain within the past 3 months
• Diagnosed myofascial pain syndrome or fibromyalgia
• History of cervical spine injury or neurological conditions affecting upper limbs
• Use of analgesic or muscle relaxant medication within 48 hours prior to testing
• Pregnancy
• Contraindications to ESWT (e.g., bleeding disorders, pacemaker, malignancy in treatment area)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: ESWT; Participants in this arm will receive a single session of extracorporeal shock wave therapy (ESWT) applied to the upper trapezius muscle (2300 waves in total).	Device: Extracorporeal Shock Wave Therapy; A single session of focused extracorporeal shock wave therapy (ESWT) applied to the upper trapezius muscle (2300 shocks). The treatment is applied to the muscle belly region with coupling gel, without local anesthesia. The protocol is designed to assess the acute effects of ESWT on muscle stiffness measured using shear-wave elastography.
No Intervention: Control group; Participants in this arm will not receive any therapeutic intervention. Muscle stiffness of the upper trapezius will be measured at the same time points as in the experimental group using shear-wave elastography, to evaluate the natural variability in stiffness and to serve as a comparison for the effects of ESWT.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Trapezius Muscle Stiffness	Muscle stiffness of the upper trapezius will be measured using shear-wave elastography (SWE). The measure represents the shear modulus (in kilopascals) of the muscle tissue, as quantified by ultrasound imaging. Measurements will be taken with the participant in a standardized seated position, with minimal muscle activity.	Baseline and Immediately Post-Intervention

Collaborators and Investigators

• Sponsor: University of Primorska
• Investigators: Principal Investigator: Kozinc, PhD, University of Primorska, Faculty of Health Sciences

Study record dates

Study Major Dates

• Study Start (Actual): April 24, 2025
• Primary Completion (Actual): May 25, 2025
• Study Completion (Actual): June 10, 2025

Study Registration Dates

• First Submitted: April 11, 2025
• First Submitted That Met QC Criteria: April 11, 2025
• First Posted (Actual): April 18, 2025

Study Record Updates

• Last Update Posted (Actual): April 1, 2026
• Last Update Submitted That Met QC Criteria: March 31, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Therapeutics; Physical Therapy Modalities; Rehabilitation; Ultrasonic Therapy; Diathermy; Hyperthermia, Induced; Extracorporeal Shockwave Therapy
• Other Study ID Numbers: ESWT_Trapezius

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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