Skip to main content
OpenTrials
Not Yet Recruiting

NCT Number: NCT07468786

Masseter Muscle Thickness in Individuals With Chronic Neck Pain

The primary objective of our study is to compare the thickness of the masseter muscle, measured by ultrasound, in individuals with chronic neck pain to that of healthy individuals. The secondary objective of the study is to examine the relationships between masseter muscle thickness and pain intensity, neck disability level, pain catastrophizing level, and clinical diagnostic criteria in individuals with chronic neck pain.

Not Yet Recruiting

Trial opening soon.

Get Notified

Key information

Conditions

Masseter Muscle Chronic Neck Pain Ultrasonographic

Age range

18 year–45 year

Sex eligibility

All sexes

Study type

Observational

Primary location

Hasan Kalyoncu University

Gaziantep, Şahinbey, 27000, Turkey (Türkiye)

About this study

The aim of this study is to evaluate masseter muscle thickness in individuals with chronic neck pain using ultrasonography and to compare it with healthy individuals. Thus, it is intended to reveal possible morphological changes related to the craniomandibular system in chronic neck pain and to determine whether these changes contribute to clinical evaluations. The literature reports that there are biomechanical and neuromuscular connections between the temporomandibular system and the cervical spine, and that changes in masseter muscle activity and morphology may be related to neck pain. The literature emphasizes that there are biomechanical, neuromuscular, and sensory connections between the temporomandibular system and the cervical spine, and that dysfunctions in these two regions may influence each other reciprocally. The masseter muscle, in particular, being one of the primary muscles of the temporomandibular system, may exhibit increased muscle activity, parafunctional habits, and morphological adaptations due to central sensitization mechanisms in chronic pain conditions. Chronic neck pain is reported to be more common in individuals with temporomandibular disorders, along with increased muscle sensitivity and functional limitations, and this condition is associated with cervical pain severity and disability level. Ultrasonography is a reliable, valid, and non-invasive method for assessing muscle thickness and is widely used to evaluate the morphological characteristics of the masseter muscle. Measuring masseter muscle thickness by ultrasonography allows for the evaluation of the muscle's structural response to functional loading and enables comparisons between different clinical groups. However, the literature shows that studies comparing possible changes in masseter muscle thickness in individuals with chronic neck pain with healthy individuals are limited, and this relationship has not been sufficiently elucidated. Accordingly, the primary objective of this study is to compare the masseter muscle thickness measured by ultrasonography in individuals with chronic neck pain with that in healthy individuals. The secondary objective of the study is to examine the relationships between masseter muscle thickness and pain intensity, neck disability level, pain catastrophizing level, and clinical diagnostic criteria in individuals with chronic neck pain.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Be between the ages of 18 and 45
  • Have neck pain that has persisted for at least 3 months
  • Agree to participate in the study voluntarily and provide written informed consent

Exclusion criteria

  • History of cervical spine surgery or severe trauma
  • Diagnosis of cervical radiculopathy, myelopathy, or neurological disease
  • Rheumatic, inflammatory, or systemic musculoskeletal diseases
  • Diagnosed temporomandibular joint disorder (TMD)
  • Diagnosis of bruxism or a pronounced habit of teeth clenching/grinding
  • History of manual therapy, injection, or surgical intervention in the face, jaw, or neck region within the last 6 months
  • Currently undergoing orthodontic treatment or history of orthodontic treatment within the last 6 months
  • Cognitive impairment or conditions that prevent understanding and responding to questionnaires

Treatment and study plan

Primary outcomes

  1. Ultrasonographic Measurement

    Time frame: through of the study, average 3 months

    Masseter muscle thickness will be assessed using the B-mode ultrasound method with a 7.5-10 MHz frequency linear probe on an ALEXUS brand ultrasound device. During measurements, participants will be positioned sitting upright, with the head in a neutral position and the jaw at rest (teeth not in occlusion). Prior to measurement, participants will be instructed to avoid activities such as intense chewing or gum chewing for the last 24 hours. The measurement point will be determined as the midpoint of the line between the zygomatic arch and the mandibular angle. The linear probe will be placed parallel to the long axis of the masseter muscle fibers, perpendicular to the skin surface, and with minimal pressure applied. The ultrasound image will clearly distinguish the skin, subcutaneous tissue, and superficial and deep fascial borders of the masseter muscle.

Secondary outcomes

  1. Visual Analog Scale (VAS)

    Time frame: through of the study, average 3 months

    The VAS is a one-dimensional measurement tool used to assess the intensity of pain as perceived by the individual. The scale consists of a horizontal line with endpoints defined as "0 = no pain" and "10 = unbearable pain," on which the individual marks their current pain level. Participants are asked to rate the intensity of their neck pain, and the distance from the starting point to the marked point is measured in centimeters or millimeters and scored. Higher scores indicate higher pain intensity.

  2. Neck Disability Index - NDI

    Time frame: through of the study, average 3 months

    The Neck Disability Index (NDI) is a multidimensional self-report scale developed to assess the level of functional limitation associated with neck pain, covering activities of daily living. The scale consists of a total of 10 items covering pain, personal care, lifting, reading, headaches, concentration, work, driving, sleep, and recreation. Each item is scored from 0 to 5, and the total score ranges from 0 to 50. Higher scores indicate an increased level of disability related to the neck. The validity and reliability study of the 7-item questionnaire in Turkish was conducted by Emine Aslan and colleagues in 2008.

  3. Pain Catastrophizing Scale

    Time frame: through of the study, average 3 months

    The Pain Catastrophizing Scale was developed to assess an individual's negative cognitive and emotional responses to their pain experience. The scale consists of three subscales: rumination (persistent thinking), magnification, and helplessness. The scale is answered using a Likert-type rating, and a total score is calculated. High scores indicate an increased tendency to catastrophize pain.

  4. Northwick Park Neck Pain Questionnaire (NPQ)

    Time frame: through of the study, average 3 months

    The Northwick Park Neck Pain Questionnaire (NPQ) is a self-report measure that assesses functional impairment and symptom severity associated with neck pain. The scale consists of items covering pain, paresthesia, sleep, social life, and daily activities. Participants select the statement that best applies to them for each item. The total score reflects the level of functional impairment, with higher scores indicating greater disability and symptom severity.

Study contacts

Contact information is provided by the study sponsor or research team.

Tuğba GÖNEN, Asisst. Prof. Dr.

CONTACT

[email protected]

505 090 58 46

Sponsors and collaborators

Lead sponsor

Hasan Kalyoncu University

Other

Registry information

Official study title

Comparison of Masseter Muscle Thickness Measured by Ultrasonography in Individuals With Chronic Neck Pain Compared to Healthy Individuals

Important dates

Study start
2026
Primary completion
2026
Study completion
2026
First posted
Mar 13, 2026
Registry last updated
Mar 13, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.