Laser Therapy for Patients With Nonspecific Neck Pain

Comparison of High-intensity Laser Therapy and Low-Level Laser Therapy in Patients With Non-specific Neck Pain

Background and Purpose: Neck pain is widespread and stands as the sixth most common cause of disability globally. While laser therapy has been used for many years to treat non-specific neck pain (NNP), there is still a shortage of research directly comparing different laser modalities. The aim of this study was to evaluate and compare the therapeutic effectiveness of low-level laser therapy (LLLT) and high intensity laser therapy (HILT) in managing NNP.

Methods: sixty patients diagnosed with NNP were equally randomized into three groups. HILT group received 10 weeks of HILT, LLLT group received 10 weeks of LLLT and a control group that received a home program. Outcome measures were evaluated at baseline and after the intervention period and included pain intensity, neck disability, active cervical range of motion (ROM), and quality of life.

Study Overview

• Status: Completed
• Conditions: Neck Pain; Non Specific Neck Pain
• Intervention / Treatment: Other: HILT; Other: CONTROL; Other: LLLT

Detailed Description

Study Design This study was designed as randomized comparative trial. The study procedures were conducted in the electrotherapy laboratory in the Department of Rehabilitation and Health Sciences, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia between March 2023 and April 2024. The study involved recruitment of 75 subjects from the university hospital and local clinics. Initial evaluation was performed by an orthopedist. The study sample included participants diagnosed with chronic non-specific neck pain (NNP) according to clinical and radiological tests. Study subjects were randomly assigned to one of three groups high intensity laser therapy (HILT) group, low-level laser therapy (LLLT) group, and a control group. The HILT group subjects underwent 10 weeks of HILT in addition to a home exercise program while the LLLT group subjects underwent 10 weeks of LLLT in addition to a home exercise program. The third group was a control group where group subjects performed only a home exercise program and did not receive laser therapy. The use of analgesics or nonsteroidal anti-inflammatory medications was not allowed during the intervention period (17).

The randomization process was conducted using SPSS statistical software, following a 1:1 allocation ratio and stratified by center, with random block sizes of four to ensure balanced distribution. An independent researcher, who was not involved in recruiting participants or delivering the interventions, generated the randomization sequence. Group assignments were recorded on numbered cards and sealed in opaque envelopes by this independent researcher. These envelopes were later opened by the intervention researchers, who administered the respective treatment according to group allocation.

Blinding was maintained throughout the study. All participants were unaware of their assigned group, ensuring subject blinding. Although the therapists delivering the treatments knew which group participants belonged to, they were blinded to the specific laser parameters, as these settings were predetermined by an independent researcher. The therapists' role was limited to implementing standardized treatment protocols without access to detailed device settings. Furthermore, all outcome evaluations were performed by an assessor who was blinded to group allocation, thereby minimizing assessment bias and maintaining the integrity of the study's double-blind design.

• Study Type: Interventional
• Enrollment (Actual): 60
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Saudi Arabia
  • Al Kharj, Saudi Arabia, 16242
    • Mohammed Hegazy

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• chonic neck pain lasting more than 30 days with no evidence of foraminal compression;
• age 18 years or older;
• experiencing considerable pain, stiffness, or discomfort localized to the neck area, without associated numbness or radiation of pain to the upper limbs;
• a visual analog scale (VAS) pain rating of 3 or above;
• no therapeutic intervention within the last month

Exclusion Criteria:

• Previous cervical spine trauma or surgery;
• significant cervical disc prolapse, cervical nerve root compression or spinal cord manifestations;
• history of severe and frequent migraines, fibromyalgia, shoulder diseases, rheumatic or rheumatoid diseases, severe osteoporosis, mental illnesses, significant spinal deformities, or serious cardiovascular, pulmonary, or neurological diseases.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: HILT; The first phase consisted of rapid manual scanning, delivering a total energy of 1000 J/cm². During the second phase, HILT was applied to eight trigger points, with four applications per point, continuing until pain reduction reached approximately 70-80%; a total of 200 J was delivered in this phase. The final phase was performed with slow manual scanning with the same parameters as the initial phase. The complete HILT procedure lasted around 30 minutes, with a total energy dose of approximately 2050 J (19).	Other: HILT; The first phase consisted of rapid manual scanning, delivering a total energy of 1000 J/cm². During the second phase, HILT was applied to eight trigger points, with four applications per point, continuing until pain reduction reached approximately 70-80%; a total of 200 J was delivered in this phase. The final phase was performed with slow manual scanning with the same parameters as the initial phase. The complete HILT procedure lasted around 30 minutes, with a total energy dose of approximately 2050 J (19).; Other Names: Home program; Other: CONTROL; The home program involved stretching exercises for levator scapulae and upper trapezius, strengthening exercises for neck extensors, and scapular stabilizer exercises. Each exercise was executed with a 5-second hold and 10 repetitions per set, for a total of three sets repeated three times per week for 10 weeks.
Experimental: LLLT; LLLT sessions were carried out using the diode laser device (Chattanooga Group, USA) of gallium-aluminum-arsenide (GaAlAs, infrared laser) with an 850 nm wavelength, 800 mW power, and constant wave with 1 cm spot size was utilized for the treatment procedures. The laser probe was positioned directly on specific points along the cervical spine while the participant's head remained in a neutral position. Each point was treated for 2 minutes. A total of eight points were marked bilaterally over the trapezius and sternocleidomastoid muscles, covering an area of 24 cm². The total treatment duration was 18 minutes, with an energy dose of 2 J/cm² applied to each point (20).	Other: CONTROL; The home program involved stretching exercises for levator scapulae and upper trapezius, strengthening exercises for neck extensors, and scapular stabilizer exercises. Each exercise was executed with a 5-second hold and 10 repetitions per set, for a total of three sets repeated three times per week for 10 weeks.; Other: LLLT; The laser probe was positioned directly on specific points along the cervical spine while the participant's head remained in a neutral position. Each point was treated for 2 minutes. A total of eight points were marked bilaterally over the trapezius and sternocleidomastoid muscles, covering an area of 24 cm². The total treatment duration was 18 minutes, with an energy dose of 2 J/cm² applied to each point (20).; Other Names: HOME PROGRAM
Active Comparator: CONTROL; The home program involved stretching exercises for levator scapulae and upper trapezius, strengthening exercises for neck extensors, and scapular stabilizer exercises. Each exercise was executed with a 5-second hold and 10 repetitions per set, for a total of three sets repeated three times per week for 10 weeks.	Other: CONTROL; The home program involved stretching exercises for levator scapulae and upper trapezius, strengthening exercises for neck extensors, and scapular stabilizer exercises. Each exercise was executed with a 5-second hold and 10 repetitions per set, for a total of three sets repeated three times per week for 10 weeks.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pain intensity	VAS is a reliable tool for measuring pain intensity. Each participant was asked to mark a point on a 10 cm line corresponding to the severity of their pain, with scores ranging from 0 to 10-where 0 indicates no pain and 10 represents the most severe pain. Previous research has demonstrated that the VAS is a reliable and valid tool for assessing the intensity of neck pain	10 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Active ROM of the cervical spine	A universal goniometer was employed to quantify the angle of motion in each direction. Each movement was measured three times to ensure consistency, and the mean of the three readings was recorded as the final value. This standardized method minimizes measurement error and improves reproducibility. Previous studies have reported that cervical active ROM assessment using a goniometer provides excellent intra- and inter-rater reliability, making it a valid and dependable tool for evaluating neck mobility (23).	10 weeks
Functional disability	The Neck Disability Index (NDI) was employed to assess functional disability in the study participants. This instrument consists of 10 items divided into two domains: neck pain-related symptoms and the capacity to carry out daily activities. Each item is scored from 0 to 5, yielding a maximum total score of 50, with higher scores indicating greater cervical functional impairment (24). The NDI was expressed as a percentage of disability, determined by the formula (total score/50 × 100). The NDI has good internal consistency and test-retest reliability	10 weeks
SF-36 Quality of life	The SF-36 consists of 36 items that assess both physical and mental health, allowing participants to rate their perceived health status on a scale from 0 to 100, where 0 indicates the poorest health and 100 indicates the best possible health (26). This questionnaire provides a reliable measure of two distinct domains: physical and mental health (27).	10 weeks

Collaborators and Investigators

• Sponsor: Prince Sattam Bin Abdulaziz University

Publications and helpful links

General Publications

• Ezzati K, Laakso EL, Saberi A, Yousefzadeh Chabok S, Nasiri E, Bakhshayesh Eghbali B. A comparative study of the dose-dependent effects of low level and high intensity photobiomodulation (laser) therapy on pain and electrophysiological parameters in patients with carpal tunnel syndrome. Eur J Phys Rehabil Med. 2020 Dec;56(6):733-740. doi: 10.23736/S1973-9087.19.05835-0. Epub 2019 Nov 18.
• Alayat MSM, Alshehri MA, Shousha TM, Abdelgalil AA, Alhasan H, Khayyat OK, Al-Attar WS. The effectiveness of high intensity laser therapy in the management of spinal disorders: A systematic review and meta-analysis. J Back Musculoskelet Rehabil. 2019;32(6):869-884. doi: 10.3233/BMR-181341.

Study record dates

Study Major Dates

• Study Start (Actual): March 1, 2023
• Primary Completion (Actual): March 1, 2024
• Study Completion (Actual): April 1, 2024

Study Registration Dates

• First Submitted: November 18, 2025
• First Submitted That Met QC Criteria: November 30, 2025
• First Posted (Estimated): December 4, 2025

Study Record Updates

• Last Update Posted (Estimated): December 4, 2025
• Last Update Submitted That Met QC Criteria: November 30, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: neck pain; neck disability; laser
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Neck Pain; Therapeutics; Laser Therapy; Phototherapy; Low-Level Light Therapy
• Other Study ID Numbers: RHPT/022/041

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