Comparative Effect of High-Level Versus Low-Level Laser Therapy on Nerve Root Function Among Healthy Young Adults: A Randomized Controlled Trial

November 21, 2025 updated by: Taif A. M. Omran

Study title: Comparative Effect of High-Level Versus Low-Level Laser Therapy on Nerve Root Function Among Healthy Young Adults: A Randomized Controlled Trial You are invited to participate in a research study to investigate the short-term effect of high-intensity laser therapy (HILT), low-level laser therapy (LLLT), and sham laser on nerve root function among healthy adults.

Participation is entirely voluntary, and you may withdraw from the study at any time without penalty or need for justifications if you choose to do so.

What is the aim of the study? The objective of the current study is to investigate the short-term effect of high-intensity laser therapy (HILT), low-level laser therapy (LLLT), and sham laser on nerve root function among healthy adults.

Type of participants? We are recruiting participants aged 18-30 years of both genders without any musculoskeletal or neurological disorder involving the upper extremities, non-smokers, and if they expressed their wellness to participate in the current study.

What will participants be asked to do? The purpose of this study is to investigate the short-term effect of high-intensity laser therapy, low-level laser therapy, and sham laser on nerve root function among healthy adults.

If you agree to take part:

  • First, we will check if you are eligible for the study.
  • If you are eligible and give your consent, you will be randomly placed into one of three groups:

    1. High-intensity laser therapy group
    2. Low-level laser therapy group
    3. Sham (placebo) group - in this group, the laser device will look and feel the same, but it will not actually deliver laser treatment.
  • If you are in the sham group, you will not receive active laser therapy. This is important for the scientific accuracy of the study, as it allows us to compare the effects of real laser therapy with no treatment. You will not know which group you are in during the study, but you will be informed after your participation is complete.
  • You will attend 9 short sessions over 3 weeks (3 sessions per week). Each session will last about 5-10 minutes.
  • To measure nerve function before laser application (Step 1):

    1. A small gel will be used to place two sensors on your head (these can be removed easily).
    2. Three nerves in your arm will be tested using very light, safe electrical pulses delivered through a small hand-held electrode held in place with a strap.
    3. This helps us measure how your nerves are working before laser treatment by measuring the peak-to-peak amplitude and latency of N20 point of the brain through analyzing the brain waves.
  • Laser or sham application (Step 2):

    1. A researcher will apply the laser (or sham) to three spots on your neck.
    2. Each spot will receive laser for about 2 minutes.
    3. The laser used is safe, does not cause heat, and you will not feel any burning.
  • Measuring nerve function again (Step 3):

The same nerve test from step 1 will be repeated to see if there are any changes after the laser application.

  • Men do not need to remove any clothing.
  • Women who wear a headscarf will be asked to temporarily remove it so the head sensors can be placed. This will be done in a private room by a female researcher only, with doors locked and separators used to ensure complete privacy.
  • Male participants will also be attended to by a male researcher in the same respectful and private way.
  • It is very important to note that you may be assigned to a group where the laser is not actually turned on (sham group). This is important for the scientific accuracy of the study.
  • You will be told which group you were in after the study is completed.

Study Overview

Study Type

Interventional

Enrollment (Estimated)

58

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Individuals deemed to be eligible to participate in the current study if they aged between 18 and 30 years of both genders, without any musculoskeletal or neurological disorder involving the upper extremities, non-smokers, and if they expressed their wellness to participate in the current study.

Exclusion Criteria:

  • Individuals will be excluded if they have a history of cervical spine disorders; significant cervical disc herniation, spinal narrowing, cervical nerve root compression, or cervical spinal cord dysfunction; a history of severe and frequent migraines, shoulder diseases, fibromyalgia, rheumatic or rheumatoid diseases, mental illnesses, severe osteoporosis, significant spinal deformities, or serious neurological, cardiovascular, or pulmonary conditions; the presence of fever, infection, tumors; cognitive or emotional disorders; or pregnant or nursing women (Xie et al., 2025).

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

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

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: HILT group
Participants in HILT group will receive laser therapy with a wavelength of 1064 nm, frequency of 25 Hz, output power of 7 W, and energy dose of 120 J/cm^2, intervention will be delivered through non-contact mode, by using the Zimmer MedizinSysteme device (OptonPro, Germany) to deliver high-intensity laser over C6, C7, and C8 nerve roots as they exit the spinal column.
Participants in HILT group will receive laser therapy with a wavelength of 1064 nm, frequency of 25 Hz, output power of 7 W, and energy dose of 120 J/cm^2, intervention will be delivered through non-contact mode, by using the Zimmer MedizinSysteme device (OptonPro, Germany) to deliver high-intensity laser over C6, C7, and C8 nerve roots as they exit the spinal column.
Active Comparator: LLLT group
Participants in LLLT group will receive laser therapy with wavelength of 905nm, frequency of 5 kHz output power of 25mW, and energy dose of 2 J/cm^2, intervention will be delivered through contact mode, by using the Enraf-Nonius Endolaser device (South Africa) to deliver low-level laser over C6, C7, and C8 nerve roots as the exit the spinal column.
Participants in LLLT group will receive laser therapy with wavelength of 905nm, frequency of 5 kHz output power of 25mW, and energy dose of 2 J/cm^2, intervention will be delivered through contact mode, by using the Enraf-Nonius Endolaser device (South Africa) to deliver low-level laser over C6, C7, and C8 as they exit the spinal column.
Sham Comparator: Sham laser group
For the participants in the sham group, the same procedure will be followed, but with having the laser device turned off.
For the participants in the sham group, the same procedure will be followed, but with having the laser device turned off.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
N20 peak-to-peak amplitude and latency
Time Frame: N20 peak-to-peak amplitude and latency of C6, 7, and C8 will be measured at baseline and immediately after laser therapy application.
The main outcome measure used to assess the nerve root function will be the N20 peak-to-peak amplitude and latency by using the dermatomal somatosensory evoked potentials (DSEPs).
N20 peak-to-peak amplitude and latency of C6, 7, and C8 will be measured at baseline and immediately after laser therapy application.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Collaborators

Investigators

  • Principal Investigator: Taif Omran, University of Sharjah

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

November 24, 2025

Primary Completion (Estimated)

December 31, 2025

Study Completion (Estimated)

December 31, 2025

Study Registration Dates

First Submitted

November 21, 2025

First Submitted That Met QC Criteria

November 21, 2025

First Posted (Estimated)

December 3, 2025

Study Record Updates

Last Update Posted (Estimated)

December 3, 2025

Last Update Submitted That Met QC Criteria

November 21, 2025

Last Verified

November 1, 2025

More Information

Terms related to this study

Other Study ID Numbers

  • REC-25-06-24-03-PG

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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