Comparison of mechanical properties of masticatory muscles and oculomotor control in individuals with and without chronic mechanical neck pain: A cross- sectional study

Comparison of mechanical properties of masticatory muscles and oculomotor control in individuals with and without chronic mechanical neck pain: A cross- sectional study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Comparison of mechanical properties of masticatory muscles and oculomotor control in individuals with and without chronic mechanical neck pain: A cross- sectional study Spoorti Kotian, Prabu Raja G, Shyamasunder Bhat N, Anupama Prabhu This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7013908/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 13 You are reading this latest preprint version Abstract Background : Chronic mechanical neck pain (CMNP) is often associated with visual impairments, headaches, and temporomandibular dysfunctions. The plethora of symptoms associated with neck pain results from the densification of the deep cervical fascia and its myofascial continuum. Although there exists an anatomical myofascial link between the neck, the head, and Tenon's capsule of the eye, their functional interrelationship remains unclear. This study compares the mechanical properties of masticatory and neck muscles and oculomotor control in individuals with and without CMNP. Methods : A comparative cross-sectional study was performed involving 26 participants with chronic mechanical neck pain and 26 healthy individuals matched for age and gender, aged between 18 and 45 years. The outcome includes the biomechanical properties (stiffness, frequency, and decrement) of the head and neck muscles using myotonpro and the oculomotor control, evaluated through the smooth pursuit neck torsion (SPNT) test using videonystagmography. Results : Independent t-test revealed that there were statistically significant differences in the frequency Hz (p= 0.001) and stiffness N/m (p= 0.01) of the temporalis and masseter muscles, suggesting increased tonus and stiffness in the neck pain group compared to the healthy individuals. In addition, a significant reduction in vertical downward gain of the right eye during right trunk torsion was observed in the CMNP group (mean difference = 0.13, p = 0.032, effect size = 0.35), whereas vertical upward gains and horizontal gains showed no statistically significant differences between participants with and without neck pain. Conclusion : Individuals with CMNP demonstrate modifications in the mechanical properties of masticatory muscles, along with noticeable impairments in oculomotor control. The findings underscore the importance of implementing comprehensive assessment and management strategies that specifically address both myofascial and sensorimotor dysfunctions in CMNP. Trial registration: The trial registration number for this study is IEC 828-2021. The trial was registered with the Clinical Trials Registry, India CTRI/2022/02/040383. Registration date: 17/02/2022. Cervical pain Connective tissue Eye movements Muscle stiffness Visual disorders Figures Figure 1 Figure 2 Figure 3 Figure 4 Background Mechanical neck pain (MNP) represents one of the most common musculoskeletal disorders and continues to be one of the foremost causes of global impairment, with a prevalence rate of 37% [1]. Individuals who experience MNP usually show improvement within two months; however, approximately 50% continue to suffer from long-term pain, potentially leading to chronic MNP [2]. Chronic mechanical neck pain (CMNP) is frequently associated with temporomandibular joint (TMJ) disorders, tension-type headaches, and oculomotor dysfunctions [3, 4]. The deep fascia (DF) creates a continuous structure that anatomically connects the human body from head to foot, forming the myofascial continuum (MC) [5-7]. In the upper quarter region (UQR), the deep cervical fascia (DCF) connects to the DF of the head and Tenon's fascia of the eye. Dysfunction in the MC of the UQR may lead to MNP and its associated plethora of symptoms, including headache and oculomotor dysfunctions [8-11]. Few authors have indicated a potential correlation between MNP and TMJ dysfunction [11]. The deep fascia contains nociceptors that can transmit pain signals directly. Additionally, proprioceptors can transform into nociceptors, converting mechanical stimuli into pain signals [11]. Research suggests that alterations in hyaluronan levels within connective tissues can influence the viscoelastic properties of myofascia, potentially leading to nociceptor activation. Furthermore, considering the MC of the upper quadrant region (UQR), modifications in the DCF may be associated with changes in the mechanical properties of the deep fascia in the head [10-11]. In addition to patients with headaches, patients with chronic neck pain often report vision-related symptoms as a significant concern. This highlights a possible connection between these conditions [11-13]. Research indicates that the smooth pursuit neck torsion test (SPNTT) is highly reliable in determining whether vision-related symptoms stem from an individual's neck condition [12-14]. One study revealed an increase in cervico-ocular reflexes in MNP patients, possibly due to impairments in proprioceptors in the cervical region [15]. Eye-related symptoms, including visual stress, fatigue, and reading challenges, are associated with abnormal proprioceptive and nociceptive signals caused by altered muscle tension in the craniocervical area [16-18]. Furthermore, the myofascial continuum between the deep cervical fascia, epicranial fascia, and Tenon's capsule in the eye indicates that dysfunctions in the deep cervical fascia may contribute to oculomotor disorders [18-20, 26]. Although there is existing research identifying the anatomical myofascial continuum in the UQR, the functional implications of these connections, especially with respect to CMNP, are still poorly understood. Cervical dysfunctions can lead to impairments beyond localized musculoskeletal symptoms, affecting various aspects of sensorimotor control, including oculomotor function [14]. Thus, this study aimed to compare the mechanical properties of the neck and masticatory muscles and oculomotor control in individuals with and without chronic MNP. This study's findings could provide new insights into cervical dysfunctions and their associated symptoms, enabling more effective clinical assessments and intervention strategies. Methods Aim: This study aimed to compare the mechanical properties of the masticatory and neck muscles and oculomotor control in individuals with and without CMNP. Primary objective : To compare the biomechanical properties (stiffness, frequency, and decrement) of the masticatory and neck muscles (temporalis, masseter, sternocleidomastoid, and upper trapezius) with and without chronic MNP using myotonpro. Secondary objective: To compare oculomotor control (SPNTT) in individuals with and without chronic MNP via videonystagmography. Study design: Comparative cross-sectional study Study setting: Centre for Sports Science, Medicine and Research, Department of Orthopaedics, Department of Speech and Hearing, Manipal Academy of Higher Education, Manipal. Participants: Males/females with CMNP for more than three months were compared with age- and sex-matched healthy individuals aged between 18 and 45 years. Sampling method: Convenience sampling method. Inclusion criteria: Group 1: Individuals suffering from chronic MNP (over three months), Group 2: Age- and sex-matched healthy individuals. Participants were screened for CMNPs using standardized clinical criteria. The inclusion criteria included self-reported neck pain persisting for more than three months, without neurological deficits or structural pathology. A brief history of pain, including the onset, side, duration, and type of pain, was obtained. Exclusion criteria: Individuals with a history of head and neck injuries within the past year, diabetic neuropathy, vestibular or balance disorders, speech and hearing disorders, a surgical history in the UQR, neurological deficits, and inflammatory and infectious conditions were excluded from the study. Oculomotor control Oculomotor control was evaluated in a controlled laboratory setting via a videonystagmography system, as shown in Figure 1. The participants were seated at a standardized distance of one meter from a digital display screen showing pursuit movements at a constant velocity. Standardized instructions were provided, and the participants were instructed to track the moving target visually while maintaining a neutral neck position. To evaluate the influence of cervical proprioception on eye movements, the SPNTT was administered. During the test, the participant’s trunk was passively rotated 45° to one side while the head and neck were maintained in a forward-facing, neutral position with the assistance of a trained examiner. The visual tracking task was then performed under this torsional condition and subsequently repeated with the trunk rotated to the opposite side. Eye movement data were recorded at both positions [12,21,22]. The entire oculomotor assessment, including participant briefing, equipment setup, and testing, was completed within approximately 30 minutes per participant. The SPNTT has demonstrated good reliability in assessing oculomotor disturbances associated with altered cervical afferent input. It effectively distinguishes individuals with neck pain from healthy controls by identifying disruptions in smooth pursuit eye movements, particularly in torsional positions [27-29]. Additionally, previous studies have shown the clinical relevance of the SPNTT in detecting proprioceptive dysfunction and abnormalities in cervico-ocular interactions in individuals with chronic neck pain [29, 30]. Mechanical properties of the myofascia The mechanical properties, including stiffness (N/m), tone (Hz), and elasticity (log decrement), were measured via myotonpro (Estonia). This non-invasive device delivers a brief mechanical impulse (0.4 N) to the skin, inducing naturally damped oscillations, from which muscle tone (Hz), stiffness (N/m), and elasticity are derived, as shown in Figure 2 [11]. Bilateral measurements were obtained at four anatomical sites: the temporalis, masseter, sternocleidomastoid (SCM), and upper trapezius muscles. The entire procedure lasted approximately twenty minutes for each participant. One study demonstrated excellent within-session reliability with an intraclass correlation coefficient (ICC = 0.94 to 0.99) [23, 24]. Statistical analysis A post hoc power analysis was performed via G*Power 3 to evaluate the difference between the means of two independent groups with a two-tailed test with an effect size of d = 1.5 and an alpha value of 0.05. The power of the study was 99% on the basis of a total sample of 52 individuals (26 individuals with chronic MNP and 26 healthy individuals without neck pain). The data were analysed via IBM SPSS Statistics (Version 18, IBM Corp., Armonk, NY, USA). The Shapiro–Wilk test was used to evaluate the normality of the data distribution, and an independent t test was conducted for comparisons between groups. Results Participants’ characteristics: Twenty-six individuals with CMNP and twenty-six healthy individuals, matched for age and sex, participated in the study. The demographic characteristics of the participants are presented in Table 1. Table 1. Demographic characteristics of the participants (to be inserted here) Mechanical properties of muscles and their fascia Frequency (Hz): There was a statistically significant difference in the frequency parameter in the left temporalis muscle, with the CMNP group showing a greater frequency than the controls did (mean difference = –7.06 Hz, p = 0.001; effect size = 0.53). A significant increase in frequency was also observed in the right masseter muscle in CMNP participants (mean difference = 0.80 Hz, p = 0.035, effect size = 0.35). The results indicate that there is a significant increase in the tonus of the temporalis and masseter muscles and their associated temporal and masseteric fascia, respectively. There was no substantial difference in the frequency of the upper trapezius and SCM (p > 0.05), as shown in Table 2 and Figure 3. Stiffness (N/m): Compared with that of the controls, the stiffness of the left temporalis muscle was significantly greater in the CMNP group (mean difference = –252.5 N/m, p = 0.016, effect size = 0.39). Similarly, right masseter muscle stiffness was significantly greater in the CMNP group (mean difference = 30.0 N/m, p = 0.039; effect size = 0.33). There was no notable difference in stiffness for the other muscle sites (p > 0.05), as shown in Table 2 and Figure 3. Logarithmic Decrement: No statistically significant group differences were observed in the decrement values for the muscles (temporalis, masseter, UT, and SCM) or their associated fascia (p > 0.05). Oculomotor control A significant reduction in vertical downwards gain of the right eye during right trunk torsion was observed in the CMNP group (mean difference = 0.13, p = 0.032; effect size = 0.35). No other directional gains (horizontal or vertical, left or right eye, in either torsional direction) demonstrated statistically significant differences (p > 0.05), as shown in Table 2 and Figure 4. Table 2. Between-group comparisons (CMNP vs. Controls) (To be inserted here) Discussion This study explored the mechanical properties of myofascia in the head and neck, along with oculomotor control, in individuals suffering from chronic mechanical neck pain (CMNP) compared with healthy controls. The results indicated significant alterations in the frequency and stiffness of specific muscles, particularly the temporalis and masseter muscles. Additionally, there was a significant decline in oculomotor performance during tasks involving torsional movements. Altered mechanical properties: Participants with CMNPs show increased stiffness and frequency in the temporalis and masseter muscles, indicating heightened myofascial tone and reduced tissue compliance. Research indicates that people with chronic neck pain often experience increased muscle tension and stiffness in the neck. These symptoms likely arise from protective guarding, pain-related reflexes, or sustained low-level muscle contractions due to poor posture [31-33]. Increased muscle activity suggests heightened neuromuscular activation or increased resting tone, likely due to protective guarding, pain reflexes, or low-level contractions from altered posture [25, 34]. Previous studies have focused primarily on the stiffness of the SCM and upper trapezius muscles in relation to neck pain [35]. Nevertheless, the findings of this study show that individuals with CMNP experience changes in the biomechanical properties of the masticatory muscles and their fascia. This may provide insights into compensatory recruitment patterns and the relationship between cervical function and masticatory muscle control [38]. These relationships are particularly significant, especially given the anatomical and functional integration between the head and neck through myofascial chains. However, the logarithmic decrement, a measure of viscoelastic damping, demonstrated no significant differences between the groups. This finding suggests that, despite alterations in tone and stiffness, the elastic recovery characteristics of the myofascial tissues remained largely intact. This may indicate that the changes observed are more reflective of early-stage or adaptive responses rather than irreversible fibrosis or structural degeneration. Impaired oculomotor control: The CMNP group presented significantly reduced vertical downwards gain in the right eye during rightward trunk torsion in the SPNTT. This finding supports previous evidence that chronic neck pain is associated with impaired sensorimotor integration affecting the cervico-ocular reflex [14, 36]. The SPNTT is a sensitive measure for assessing the contribution of the cervix to eye movement control under dynamic postural challenges [37]. The identified deficits may stem from alterations in afferent input originating from cervical proprioceptors. This alteration can result in a discrepancy between the commands for eye movement and the positional orientation of the trunk or head [14, 19]. Although only one oculomotor parameter (vertical downwards gain) reached statistical significance, the findings suggest subtle but functionally relevant impairments in sensorimotor coordination, which may contribute to symptoms such as dizziness, visual fatigue, and impaired postural control in individuals with CMNP. Clinical and functional implications: The combined findings of altered mechanical properties of the masticatory muscles and their fasciae, along with impaired oculomotor function, suggest broader neuromyofascial dysfunction in CMNP. Rehabilitation strategies for CMNP may be enhanced by emphasizing sensorimotor retraining, with a particular focus on cervicocular integration and the myofascial continuum of the head and neck. Thus, an interdisciplinary approach may be warranted in the comprehensive evaluation and management of CMNPs. Limitations and future directions: The existing sample size is deemed sufficient for the identification of moderate effects; nevertheless, it may lack the sensitivity required to detect subtle variations across all parameters. Future research should investigate the long-term changes in myofascial properties that occur after therapeutic interventions and integrate multimodal assessments, including ultrasound elastography, to evaluate deeper myofascial structures. In addition, incorporating balance, gaze stability, and quality of life in the evaluation could enhance the understanding of the clinical significance of the observed changes. Conclusion Individuals with CMNP exhibit alterations in the myofascial properties of masticatory muscles and demonstrate impairments in oculomotor control. These findings emphasize the need for comprehensive assessment and management strategies targeting both myofascial and sensorimotor dysfunctions in CMNP. Abbreviations MNP - Mechanical neck pain CMNP - Chronic mechanical neck pain SPNTT - Smooth pursuit neck torsion test MC - Myofascial continuum UQR - Upper quarter region DCF - Deep cervical fascia DF - Deep fascia SCM - Sternocleidomastoid TMJ - Temporomandibular joint Declarations Ethics approval and consent to participate The study was conducted in accordance with the Declaration of Helsinki, ensuring ethical standards. Kasturba Medical College and Kasturba Hospital Institutional Ethics Committee (Registration No. ECR/146/Inst/KA/2013/RR-19), Manipal Academy of Higher Education, Manipal, Karnataka, India, has approved the study. Approval ID is IEC 828-2021. Registration date: 17/02/2022. Consent for publication Written informed consent was obtained from individuals depicted in the images during outcome measurements for the publication of their images. Availability of data and materials The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request. Competing interests The authors declare that there are no financial or other competing interests. Funding This research did not receive any specific grants from funding agencies in the public, commercial, or not-for-profit sectors Authors' contribution PR is responsible for the study conception, design, and implementation. AP, SB, and SK have contributed to the design of the study along with PR. SK and PR were involved in data collection and analysis of the study. AP assisted PR and SB in drafting the manuscript. All the authors have given the final approval of the manuscript to be submitted for publication. Acknowledgements The authors would like to thank Mr. Prajwal, Mr. Guru, and Ms. Shalmili for their assistance during data collection. References Peng B, Yang L, Li Y, Liu T, Liu Y. 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Between-group comparisons (CMNP vs. Controls) Mechanical properties of the muscles and their associated fascia Parameter MD 95% CI p-value Effect Size (d) Frequency (Hz) Temporalis (Rt) -2.90 [-8.4, 3] 0.332 0.16 Temporalis (Lt) -7.06 [-11.4, -2.9] 0.001* 0.53* Masseter (Rt) 0.80 [0.1, 1.5] 0.035* 0.35* Masseter (Lt) 0.50 [-0.3, 1] 0.206 0.21 SCM (Rt) 0.30 [-0.2, 0.9] 0.190 0.21 SCM (Lt) ~0.00 [-0.5, 0.6] 0.949 0.01 UT (Rt) 0.40 [-0.3, 1.3] 0.241 0.19 UT (Lt) 0.50 [-0.2, 1.3] 0.119 0.25 Stiffness (N/m) Temporalis (Rt) -176.47 [-459, 80] 0.185 0.22 Temporalis (Lt) -252.51 [-447, -57] 0.01* 0.39* Masseter (Rt) 30.00 [2, 59] 0.03* 0.33* Masseter (Lt) 7.16 [-15, 32] 0.647 0.08 SCM (Rt) -3.00 [-19, 14] 0.694 0.07 SCM (Lt) -13.00 [-29, 7] 0.220 0.20 UT (Rt) 2.00 [-20, 27] 0.819 0.04 UT (Lt) 6.14 [-21, 30] 0.641 0.08 Log Decrement (Elasticity) Temporalis (Rt) 0.09 [-0.08, 0.30] 0.256 0.18 Temporalis (Lt) 0.03 [-0.13, 0.18] 0.687 0.07 Masseter (Rt) 0.10 [-0.02, 0.21] 0.080 0.28 SCM (Rt) -0.07 [-0.20, 0.05] 0.260 0.18 SCM (Lt) -0.3 [-0.13, 0.12] 0.949 0.01 UT (Rt) 0.01 [-0.07, 0.11] 0.763 0.05 UT (Lt) 0.02 [-0.07, 0.11] 0.628 0.07 Oculomotor control – SPNTT Gains Vertical Downward Gain (Rt Eye, Rt torsion) 0.13 [0.02, 0.26] 0.03* 0.35* Horizontal & other Vertical Gains (all directions) - - > 0.05 < 0.3 Rt = Right, Lt = Left, CMNP-Chronic mechanical neck pain, SCM-Sternocleidomastoid, UT-Upper trapezius, SPNTT-Smooth pursuit neck torsion test; ns-not significant. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 24 Sep, 2025 Reviews received at journal 29 Aug, 2025 Reviews received at journal 18 Aug, 2025 Reviews received at journal 12 Aug, 2025 Reviewers agreed at journal 02 Aug, 2025 Reviewers agreed at journal 31 Jul, 2025 Reviews received at journal 31 Jul, 2025 Reviewers agreed at journal 30 Jul, 2025 Reviewers agreed at journal 30 Jul, 2025 Reviewers invited by journal 30 Jul, 2025 Editor assigned by journal 05 Jul, 2025 Submission checks completed at journal 05 Jul, 2025 First submitted to journal 30 Jun, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7013908","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":495509843,"identity":"4857f286-b596-483b-ac54-e48d5ed9d23f","order_by":0,"name":"Spoorti Kotian","email":"","orcid":"","institution":"Manipal Academy of Higher Education","correspondingAuthor":false,"prefix":"","firstName":"Spoorti","middleName":"","lastName":"Kotian","suffix":""},{"id":495509845,"identity":"dc7a5b75-a972-43bc-85e8-cb67819b41a5","order_by":1,"name":"Prabu Raja 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Education","correspondingAuthor":false,"prefix":"","firstName":"Shyamasunder","middleName":"Bhat","lastName":"N","suffix":""},{"id":495509848,"identity":"81faf02b-5e50-43f4-9026-904296f426b6","order_by":3,"name":"Anupama Prabhu","email":"","orcid":"","institution":"Manipal Academy of Higher Education","correspondingAuthor":false,"prefix":"","firstName":"Anupama","middleName":"","lastName":"Prabhu","suffix":""}],"badges":[],"createdAt":"2025-06-30 20:08:16","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7013908/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7013908/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":88692146,"identity":"240e2e3a-65cc-4832-ac4e-91c8105c8f4a","added_by":"auto","created_at":"2025-08-09 15:02:54","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1075027,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSmooth pursuit neck torsion test (SPNTT)\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7013908/v1/6a2f1e2d1cbaf4f170765de9.png"},{"id":88691585,"identity":"86b5e115-6b78-4f0f-9f02-4f21db1e220d","added_by":"auto","created_at":"2025-08-09 14:46:54","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":479080,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eEvaluation of mechanical properties using myotonpro\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7013908/v1/84b79d5e345773c230680808.png"},{"id":88691355,"identity":"d8fcfdcf-a05b-40a4-ad54-1ee63b85a7b9","added_by":"auto","created_at":"2025-08-09 14:38:54","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":264293,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eBetween-group comparison of mechanical properties\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCMNP- Chronic mechanical neck pain, SCM-Sternocleidomastoid, Upper Trap -Upper Trapezius\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7013908/v1/93c097871f56cc023f930fe7.png"},{"id":88691354,"identity":"e165a6a8-81ab-4f89-a290-bdd8ef55cd6b","added_by":"auto","created_at":"2025-08-09 14:38:54","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":127569,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eBetween-group comparison of the smooth pursuit neck torsion test\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCMNP- Chronic mechanical neck pain\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7013908/v1/9cd9fcd8dd3998fb097b83bc.png"},{"id":88692576,"identity":"dab51528-ffed-473b-ab0a-408898c78a95","added_by":"auto","created_at":"2025-08-09 15:10:56","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3445966,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7013908/v1/22f4e54b-0532-4b53-9bdc-c859ad536392.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Comparison of mechanical properties of masticatory muscles and oculomotor control in individuals with and without chronic mechanical neck pain: A cross- sectional study","fulltext":[{"header":"Background","content":"\u003cp\u003eMechanical neck pain (MNP) represents one of the most common musculoskeletal disorders and continues to be one of the foremost causes of global impairment, with a prevalence rate of 37% [1]. Individuals who experience MNP usually show improvement within two months; however, approximately 50% continue to suffer from long-term pain, potentially leading to chronic MNP [2]. Chronic mechanical neck pain (CMNP) is frequently associated with temporomandibular joint (TMJ) disorders, tension-type headaches, and oculomotor dysfunctions [3, 4].\u003c/p\u003e\n\u003cp\u003eThe deep fascia (DF) creates a continuous structure that anatomically connects the human body from head to foot, forming the myofascial continuum (MC) [5-7]. In the upper quarter region (UQR), the deep cervical fascia (DCF) connects to the DF of the head and Tenon\u0026apos;s fascia of the eye. Dysfunction in the MC of the UQR may lead to MNP and its associated plethora of symptoms, including headache and oculomotor dysfunctions [8-11]. Few authors have indicated a potential correlation between MNP and TMJ dysfunction [11].\u003c/p\u003e\n\u003cp\u003eThe deep fascia contains nociceptors that can transmit pain signals directly. Additionally, proprioceptors can transform into nociceptors, converting mechanical stimuli into pain signals [11]. Research suggests that alterations in hyaluronan levels within connective tissues can influence the viscoelastic properties of myofascia, potentially leading to nociceptor activation. Furthermore, considering the MC of the upper quadrant region (UQR), modifications in the DCF may be associated with changes in the mechanical properties of the deep fascia in the head [10-11].\u003c/p\u003e\n\u003cp\u003eIn addition to patients with headaches, patients with chronic neck pain often report vision-related symptoms as a significant concern. This highlights a possible connection between these conditions [11-13]. Research indicates that the smooth pursuit neck torsion test (SPNTT) is highly reliable in determining whether vision-related symptoms stem from an individual\u0026apos;s neck condition [12-14].\u003c/p\u003e\n\u003cp\u003eOne study revealed an increase in cervico-ocular reflexes in MNP patients, possibly due to impairments in proprioceptors in the cervical region [15]. Eye-related symptoms, including visual stress, fatigue, and reading challenges, are associated with abnormal proprioceptive and nociceptive signals caused by altered muscle tension in the craniocervical area [16-18].\u0026nbsp;Furthermore, the myofascial continuum between the deep cervical fascia, epicranial fascia, and Tenon\u0026apos;s capsule in the eye indicates that dysfunctions in the deep cervical fascia may contribute to oculomotor disorders [18-20, 26].\u003c/p\u003e\n\u003cp\u003eAlthough there is existing research identifying the anatomical myofascial continuum in the UQR, the functional implications of these connections, especially with respect to CMNP, are still poorly understood. Cervical dysfunctions can lead to impairments beyond localized musculoskeletal symptoms, affecting various aspects of sensorimotor control, including oculomotor function [14]. Thus, this study aimed to compare the mechanical properties of the neck and masticatory muscles and oculomotor control in individuals with and without chronic MNP. This study\u0026apos;s findings could provide new insights into cervical dysfunctions and their associated symptoms, enabling more effective clinical assessments and intervention strategies.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e\u003cem\u003eAim:\u003c/em\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eThis study\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eaimed to compare the mechanical properties of the masticatory and neck muscles and oculomotor control in individuals with and without CMNP.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ePrimary objective\u003c/em\u003e: To compare the\u0026nbsp;biomechanical properties (stiffness, frequency, and decrement) of the masticatory and neck muscles\u0026nbsp;(temporalis, masseter, sternocleidomastoid, and upper trapezius) with and without chronic MNP using myotonpro.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eSecondary objective:\u003c/em\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eTo compare\u0026nbsp;oculomotor control (SPNTT)\u0026nbsp;in individuals with and without chronic MNP\u0026nbsp;via videonystagmography.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eStudy design:\u003c/em\u003e Comparative cross-sectional study\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eStudy setting:\u003c/em\u003e Centre for Sports Science, Medicine and Research, Department of Orthopaedics, Department of Speech and Hearing, Manipal Academy of Higher Education, Manipal.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eParticipants:\u003c/em\u003e Males/females with\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eCMNP for more than three months were compared with age- and sex-matched healthy individuals aged between 18 and 45 years.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eSampling\u003c/em\u003e\u003cstrong\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003cem\u003emethod:\u003c/em\u003e Convenience sampling method.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eInclusion\u003c/em\u003e\u003cstrong\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003cem\u003ecriteria:\u003c/em\u003e Group 1: Individuals suffering from chronic MNP (over three months),\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eGroup 2: Age- and sex-matched healthy individuals.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eParticipants were screened for CMNPs using standardized clinical criteria. The inclusion criteria included self-reported neck pain persisting for more than three months, without neurological deficits or structural pathology. A brief history of pain, including the onset, side, duration, and type of pain, was obtained.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eExclusion criteria:\u003c/em\u003e Individuals with a history of head and neck injuries within the past year, diabetic neuropathy, vestibular or balance disorders, speech and hearing disorders, a surgical history in the UQR, neurological deficits, and inflammatory and infectious conditions were excluded from the study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eOculomotor control\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eOculomotor control was evaluated in a controlled laboratory setting via a videonystagmography\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003esystem, as shown in Figure 1. The participants were seated at a standardized distance of one meter from a digital display screen showing pursuit movements at a constant velocity. Standardized instructions were provided, and the participants were instructed to track the moving target visually while maintaining a neutral neck position.\u003c/p\u003e\n\u003cp\u003eTo evaluate the influence of cervical proprioception on eye movements, the SPNTT was administered. During the test, the participant\u0026rsquo;s trunk was passively rotated 45\u0026deg; to one side while the head and neck were maintained in a forward-facing, neutral position with the assistance of a trained examiner. The visual tracking task was then performed under this torsional condition and subsequently repeated with the trunk rotated to the opposite side. Eye movement data were recorded at both positions [12,21,22]. The entire oculomotor assessment, including participant briefing, equipment setup, and testing, was completed within approximately 30 minutes per participant. The SPNTT has demonstrated good reliability in assessing oculomotor disturbances associated with altered cervical afferent input. It effectively distinguishes individuals with neck pain from healthy controls by identifying disruptions in smooth pursuit eye movements, particularly in torsional positions [27-29]. Additionally, previous studies have shown the clinical relevance of the SPNTT in detecting proprioceptive dysfunction and abnormalities in cervico-ocular interactions in individuals with chronic neck pain [29, 30].\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMechanical properties of the myofascia\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe mechanical properties, including stiffness (N/m), tone (Hz), and elasticity (log decrement), were measured via myotonpro (Estonia). This non-invasive device delivers a brief mechanical impulse (0.4 N) to the skin, inducing naturally damped oscillations, from which muscle tone (Hz), stiffness (N/m), and elasticity are derived, as shown in Figure 2 [11]. Bilateral measurements were obtained at four anatomical sites: the temporalis, masseter, sternocleidomastoid (SCM), and upper trapezius muscles. The entire procedure lasted approximately twenty minutes for each participant. One study demonstrated excellent within-session reliability with an intraclass correlation coefficient (ICC = 0.94 to 0.99) [23, 24].\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA post hoc power analysis was performed via G*Power 3 to evaluate the difference between the means of two independent groups with a two-tailed test with an effect size of d = 1.5 and an alpha value of 0.05. The power of the study was 99% on the basis of a total sample of 52 individuals (26 individuals with chronic MNP and 26 healthy individuals without neck pain). The data were analysed via IBM SPSS Statistics (Version 18, IBM Corp., Armonk, NY, USA). The Shapiro\u0026ndash;Wilk test was used to evaluate the normality of the data distribution, and an independent t test was conducted for comparisons between groups.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003eParticipants\u0026rsquo; characteristics:\u0026nbsp;\u003c/strong\u003eTwenty-six individuals with CMNP and twenty-six healthy individuals, matched for age and sex, participated in the study. The demographic characteristics of the participants are presented in Table 1.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 1. Demographic characteristics of the participants (to be inserted here)\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMechanical properties of muscles and their fascia\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eFrequency (Hz):\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThere was a statistically significant difference in the frequency parameter in the left temporalis muscle, with the CMNP group showing a greater frequency than the controls did (mean difference = \u0026ndash;7.06 Hz, p = 0.001; effect size = 0.53). A significant increase in frequency was also observed in the right masseter muscle in CMNP participants (mean difference = 0.80 Hz, p = 0.035, effect size = 0.35). The results indicate that there is a significant increase in the tonus of the temporalis and masseter muscles and their associated temporal and masseteric fascia, respectively. There was no substantial difference in the frequency of the upper trapezius and SCM (p \u0026gt; 0.05), as shown in Table 2 and Figure 3.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eStiffness (N/m):\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eCompared with that of the controls, the stiffness of the left temporalis muscle was significantly greater in the CMNP group (mean difference = \u0026ndash;252.5 N/m, p = 0.016, effect size = 0.39). Similarly, right masseter muscle stiffness was significantly greater in the CMNP group (mean difference = 30.0 N/m, p = 0.039; effect size = 0.33). There was no notable difference in stiffness for the other muscle sites (p \u0026gt; 0.05), as shown in Table 2 and Figure 3.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eLogarithmic Decrement:\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNo statistically significant group differences were observed in the decrement values for the muscles (temporalis, masseter, UT, and SCM) or their associated fascia (p \u0026gt; 0.05).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eOculomotor control\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA significant reduction in vertical downwards gain of the right eye during right trunk torsion was observed in the CMNP group (mean difference = 0.13, p = 0.032; effect size = 0.35).\u003c/p\u003e\n\u003cp\u003eNo other directional gains (horizontal or vertical, left or right eye, in either torsional direction) demonstrated statistically significant differences (p \u0026gt; 0.05), as shown in Table 2 and Figure 4.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2. Between-group comparisons (CMNP vs. Controls)\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e(To be inserted here)\u003c/strong\u003e\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study explored the mechanical properties of myofascia in the head and neck, along with oculomotor control, in individuals suffering from chronic mechanical neck pain (CMNP) compared with healthy controls. The results indicated significant alterations in the frequency and stiffness of specific muscles, particularly the temporalis and masseter muscles. Additionally, there was a significant decline in oculomotor performance during tasks involving torsional movements.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAltered mechanical properties:\u0026nbsp;\u003c/em\u003eParticipants with CMNPs show increased stiffness and frequency in the temporalis and masseter muscles, indicating heightened myofascial tone and reduced tissue compliance. Research indicates that people with chronic neck pain often experience increased muscle tension and stiffness in the neck. These symptoms likely arise from protective guarding, pain-related reflexes, or sustained low-level muscle contractions due to poor posture [31-33]. Increased muscle activity suggests heightened neuromuscular activation or increased resting tone, likely due to protective guarding, pain reflexes, or low-level contractions from altered posture [25, 34].\u003c/p\u003e\n\u003cp\u003ePrevious studies have focused primarily on the stiffness of the SCM and upper trapezius muscles in relation to neck pain [35]. Nevertheless, the findings of this study show that individuals with CMNP experience changes in the biomechanical properties of the masticatory muscles and their fascia. This may provide insights into compensatory recruitment patterns and the relationship between cervical function and masticatory muscle control [38]. These relationships are particularly significant, especially given the anatomical and functional integration between the head and neck through myofascial chains.\u003c/p\u003e\n\u003cp\u003eHowever, the logarithmic decrement, a measure of viscoelastic damping, demonstrated no significant differences between the groups. This finding suggests that, despite alterations in tone and stiffness, the elastic recovery characteristics of the myofascial tissues remained largely intact. This may indicate that the changes observed are more reflective of early-stage or adaptive responses rather than irreversible fibrosis or structural degeneration.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eImpaired oculomotor control:\u0026nbsp;\u003c/em\u003eThe CMNP group presented significantly reduced vertical downwards gain in the right eye during rightward trunk torsion in the SPNTT. This finding supports previous evidence that chronic neck pain is associated with impaired sensorimotor integration affecting the cervico-ocular reflex [14, 36]. The SPNTT is a sensitive measure for assessing the contribution of the cervix to eye movement control under dynamic postural challenges [37]. The identified deficits may stem from alterations in afferent input originating from cervical proprioceptors. This alteration can result in a discrepancy between the commands for eye movement and the positional orientation of the trunk or head [14, 19].\u003cem\u003e\u0026nbsp;\u003c/em\u003eAlthough only one oculomotor parameter (vertical downwards gain) reached statistical significance, the findings suggest subtle but functionally relevant impairments in sensorimotor coordination, which may contribute to symptoms such as dizziness, visual fatigue, and impaired postural control in individuals with CMNP.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eClinical and functional implications:\u0026nbsp;\u003c/em\u003eThe combined findings of altered mechanical properties of the masticatory muscles and their fasciae, along with impaired oculomotor function, suggest broader neuromyofascial dysfunction in CMNP. Rehabilitation strategies for CMNP may be enhanced by emphasizing sensorimotor retraining, with a particular focus on cervicocular integration and the myofascial continuum of the head and neck. Thus, an interdisciplinary approach may be warranted in the comprehensive evaluation and management of CMNPs.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eLimitations and future directions:\u0026nbsp;\u003c/em\u003eThe existing sample size is deemed sufficient for the identification of moderate effects; nevertheless, it may lack the sensitivity required to detect subtle variations across all parameters. Future research should investigate the long-term changes in myofascial properties that occur after therapeutic interventions and integrate multimodal assessments, including ultrasound elastography, to evaluate deeper myofascial structures. In addition, incorporating balance, gaze stability, and quality of life in the evaluation could enhance the understanding of the clinical significance of the observed changes.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIndividuals with CMNP exhibit alterations in the myofascial properties of masticatory muscles and demonstrate impairments in oculomotor control. These findings emphasize the need for comprehensive assessment and management strategies targeting both myofascial and sensorimotor dysfunctions in CMNP.\u003c/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003e\u003cstrong\u003eMNP\u0026nbsp;\u003c/strong\u003e- Mechanical neck pain\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCMNP -\u003c/strong\u003e Chronic mechanical neck pain\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSPNTT\u003c/strong\u003e - Smooth pursuit neck torsion test\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMC\u003c/strong\u003e - Myofascial continuum\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eUQR\u003c/strong\u003e - Upper quarter region\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDCF\u003c/strong\u003e - Deep cervical fascia\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDF\u003c/strong\u003e - Deep fascia\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSCM\u0026nbsp;\u003c/strong\u003e- Sternocleidomastoid\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTMJ\u003c/strong\u003e - Temporomandibular joint\u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003cul\u003e\n \u003cli\u003e\u003cem\u003eEthics approval and consent to participate\u003c/em\u003e\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eThe study was conducted\u0026nbsp;in accordance with the Declaration of Helsinki, ensuring ethical standards.\u0026nbsp;Kasturba Medical College and Kasturba Hospital Institutional Ethics Committee (Registration No. ECR/146/Inst/KA/2013/RR-19), Manipal Academy of Higher Education, Manipal, Karnataka, India, has approved the study. Approval ID is\u0026nbsp;IEC 828-2021. Registration date: 17/02/2022.\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003e\u003cem\u003eConsent for publication\u003c/em\u003e\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eWritten informed consent was obtained from individuals depicted in the images during outcome measurements for the publication of their images.\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003e\u003cem\u003eAvailability of data and materials\u003c/em\u003e\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eThe datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003e\u003cem\u003eCompeting interests\u003c/em\u003e\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eThe authors declare that there are no financial or other competing interests.\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003e\u003cem\u003eFunding\u003c/em\u003e\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eThis research did not receive any specific grants from funding agencies in the public, commercial, or not-for-profit sectors\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003e\u003cem\u003eAuthors\u0026apos; contribution\u003c/em\u003e\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003ePR is responsible for the study conception, design, and implementation. AP, SB, and SK have contributed to the design of the study along with PR. SK and PR were involved in data collection and analysis of the study. AP assisted PR and SB in drafting the manuscript. All the authors have given the final approval of the manuscript to be submitted for publication.\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003e\u003cem\u003eAcknowledgements\u003c/em\u003e\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eThe authors would like to thank Mr. Prajwal, Mr. Guru, and Ms. Shalmili for their assistance during data collection.\u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003ePeng B, Yang L, Li Y, Liu T, Liu Y. Cervical proprioception impairment in MNP\u0026mdash;pathophysiology, clinical evaluation, and management: a narrative review. Pain Ther. 2021;10(1):1\u0026ndash;22.\u003c/li\u003e\n \u003cli\u003eLin IH, Chang KH, Liou TH, Tsou CM, Huang YC. Progressive shoulder-neck exercise on cervical muscle functions in middle-aged and senior patients with chronic MNP. Eur J Phys Rehabil Med. 2017;54(1):13\u0026ndash;21.\u003c/li\u003e\n \u003cli\u003eAyoub LJ, Seminowicz DA, Moayedi M. A meta-analytic study of experimental and chronic orofacial pain excluding headache disorders. Neuroimage Clin. 2018;20:901\u0026ndash;12.\u003c/li\u003e\n \u003cli\u003eDe las Penas CF, Cleland J, Huijbregts PA. Neck and Arm Pain Syndromes E-Book: Evidence-informed Screening, Diagnosis and Management. Philadelphia: Elsevier Health Sciences; 2011.\u003c/li\u003e\n \u003cli\u003eBlottner D, Huang Y, Trautmann G, Sun L. The fascia: continuum linking bone and myofascial bag for global and local body movement control on Earth and in Space. A scoping review. Reach. 2019;14:100030.\u003c/li\u003e\n \u003cli\u003eStecco A, Macchi V, Stecco C, Porzionato A, Day JA, Delmas V, et al. Anatomical study of myofascial continuity in the anterior region of the upper limb. J Bodyw Mov Ther. 2009;13(1):53\u0026ndash;62.\u003c/li\u003e\n \u003cli\u003eStecco L. Fascial Manipulation for Musculoskeletal Pain. Padua: Piccin; 2004.\u003c/li\u003e\n \u003cli\u003eWilke J, Schleip R, Yucesoy CA, Banzer W. Not merely a protective packing organ? A review of fascia and its force transmission capacity. J Appl Physiol (1985). 2018;124(1):234\u0026ndash;44.\u003c/li\u003e\n \u003cli\u003eMathew NR. Effect of fascial manipulation on glenohumeral internal rotation deficit in overhead athletes: a randomized controlled trial. 2016.\u003c/li\u003e\n \u003cli\u003eFernandes S, Cruz AM, Prabhu A. The plausible role of deep cervical fascia and its continuum in chronic masticatory and cervicobrachial pain: a case report. Heliyon. 2020;6(7):e04560.\u003c/li\u003e\n \u003cli\u003eRaja GP, Bhat NS, Fern\u0026aacute;ndez-de-las-Pe\u0026ntilde;as C, Gangavelli R, Davis F, Shankar R, et al. Effectiveness of deep cervical fascial manipulation and yoga postures on pain, function, and oculomotor control in patients with mechanical neck pain: study protocol of a pragmatic, parallel-group, randomized, controlled trial. Trials. 2021;22(1):1\u0026ndash;4.\u003c/li\u003e\n \u003cli\u003eMajcen Rosker Z, Vodicar M, Kristjansson E. Intervisit reliability of smooth pursuit neck torsion test in patients with chronic neck pain and healthy individuals. Diagnostics (Basel). 2021;11(5):752.\u003c/li\u003e\n \u003cli\u003eMajcen Rosker Z, Vodicar M, Kristjansson E. Is altered oculomotor control during smooth pursuit neck torsion test related to subjective visual complaints in patients with neck pain disorders? Int J Environ Res Public Health. 2022;19(7):3788.\u003c/li\u003e\n \u003cli\u003eTreleaven J. Sensorimotor disturbances in neck disorders affecting postural stability, head and eye movement control. Man Ther. 2008;13(1):2\u0026ndash;11.\u003c/li\u003e\n \u003cli\u003ede Vries J, Ischebeck BK, Voogt LP, Janssen M, Frens MA, Kleinrensink GJ, et al. Cervico-ocular reflex is increased in people with nonspecific neck pain. Phys Ther. 2016;96(8):1190\u0026ndash;5.\u003c/li\u003e\n \u003cli\u003eGupta M, Rhee DJ. Ophthalmic anaesthesia. In: Shaarawy T, editor. Glaucoma. Philadelphia: WB Saunders; 2015. p. 734\u0026ndash;48.\u003c/li\u003e\n \u003cli\u003eWright KW. Anatomy and physiology of eye movements. In: Wright KW, Spiegel PH, editors. Handbook of Pediatric Strabismus and Amblyopia. New York: Springer; 2006. p. 24\u0026ndash;69.\u003c/li\u003e\n \u003cli\u003eTreleaven J, Jull G, Low Choy N. The relationship of cervical joint position error to balance and eye movement disturbances in persistent whiplash. Man Ther. 2006;11(2):99\u0026ndash;106.\u003c/li\u003e\n \u003cli\u003eKristjansson E, Treleaven J. Sensorimotor function and dizziness in neck pain: implications for assessment and management. J Orthop Sports Phys Ther. 2009;39(5):364\u0026ndash;77.\u003c/li\u003e\n \u003cli\u003eRaja G P, Bhat S, Gangavelli R, Prabhu A, Stecco A, Pirri C, Jaganathan V, Fern\u0026aacute;ndez-de-Las-Pe\u0026ntilde;as C. Effectiveness of deep cervical fascial manipulation\u003csup\u003e\u0026reg;\u003c/sup\u003e and sequential yoga poses on pain and function in individuals with mechanical neck pain: A randomized controlled trial. life (Basel). 2023 Nov 6;13(11):2173. doi: 10.3390/life13112173. PMID: 38004313.\u003c/li\u003e\n \u003cli\u003eDaly L, Giffard P, Thomas L, Treleaven J. Validity of clinical measures of smooth pursuit eye movement control in patients with idiopathic MNP. Musculoskelet Sci Pract. 2018;33:18\u0026ndash;23.\u003c/li\u003e\n \u003cli\u003eGiffard P, Daly L, Treleaven J. Influence of neck torsion on near point convergence in subjects with idiopathic MNP. Musculoskelet Sci Pract. 2017;32:51\u0026ndash;6.\u003c/li\u003e\n \u003cli\u003eMarusiak J, Jarocka E, Jaskolska A, Jaskolski A. Influence of number of records on reliability of myotonometric measurements of muscle stiffness at rest and contraction. Acta Bioeng Biomech. 2018;20(4):123\u0026ndash;31.\u003c/li\u003e\n \u003cli\u003eBailey L, Samuel D, Warner MB. Parameters representing muscle tone, elasticity and stiffness of biceps brachii in healthy older males: symmetry and within-session reliability using the MyotonPRO. J Neurol Disord. 2013;1:116.\u003c/li\u003e\n \u003cli\u003ePoojary S, Kamani N, Raja PG. The influence of fascial manipulation on shoulder range of motion, pain, and function in individuals with Chronic shoulder pain. Journal of Bodywork and Movement Therapy.April (40) 2024,53-60, https://doi.org/10.1016/j.jbmt.2024.03.077.\u003c/li\u003e\n \u003cli\u003ePrabu Raja G, Shyamasunder Bhat N, Marie Cruz A, Prabhu A, Fernandes S, Naaz N. The anatomical myofascial continuum between the neck and eyes. Clin Anat. 2022 Apr;35(3):340-346. doi: 10.1002/ca.23835.\u003c/li\u003e\n \u003cli\u003eKristjansson E, Dall\u0026apos;Alba P. Intrarater reliability of the smooth pursuit neck torsion test in subjects with and without neck pain. Man Ther. 2002;7(4):263\u0026ndash;7.\u003c/li\u003e\n \u003cli\u003eRevel M, Andr\u0026eacute;-Deshays C, Minguet M. Cervicocephalic kinesthetic sensibility in patients with cervical pain. Arch Phys Med Rehabil. 1991;72(5):288\u0026ndash;91.\u003c/li\u003e\n \u003cli\u003eTreleaven J, Jull G, Lowchoy N. The neck torsion test and balance dysfunction in subjects with whiplash injury. Man Ther. 2003;8(2):89\u0026ndash;95.\u003c/li\u003e\n \u003cli\u003eAjimsha MS, Al-Mudahka NR, Al-Madzhar JA. Effectiveness of myofascial release for adults with chronic neck pain. Physiother Res Int. 2023.\u003c/li\u003e\n \u003cli\u003eRezkalla WKS. Multimodal approach of electrotherapy versus myofascial release in patients with chronic mechanical neck pain. Physiother Quart. 2019;27(4):6\u0026ndash;12.\u003c/li\u003e\n \u003cli\u003eRodr\u0026iacute;guez-Huguet M, et al. Immediate effects of muscle tension and pain to myofascial release. J Phys Ther Rehabil Sci. 2024.\u003c/li\u003e\n \u003cli\u003eGraven-Nielsen T, Arendt-Nielsen L. Impact of clinical and experimental pain on muscle strength and activity. Curr Rheumatol Rep. 2008;10(6):475\u0026ndash;81.\u003c/li\u003e\n \u003cli\u003eFern\u0026aacute;ndez-de-Las-Pe\u0026ntilde;as C, Cuadrado ML, Arendt-Nielsen L, Simons DG, Pareja JA. Myofascial trigger points and sensitization: an updated pain model for tension-type headache. Cephalalgia. 2007;27(5):383\u0026ndash;93.\u003c/li\u003e\n \u003cli\u003ePeng B, Wang X, Lin X, Chen J, Zhang L, Guo J, et al. A review of sensorimotor function associated with neck pain. Eur Spine J. 2011;20(2):185\u0026ndash;92.\u003c/li\u003e\n \u003cli\u003eTjell C, Rosenhall U. Smooth pursuit neck torsion test: a specific test for cervical dizziness. Am J Otol. 1998;19(1):76\u0026ndash;81.\u003c/li\u003e\n \u003cli\u003eFern\u0026aacute;ndez-de-Las-Pe\u0026ntilde;as C, Cuadrado ML, Arendt-Nielsen L, Pareja JA. Myofascial trigger points and sensitization: an updated pain model for tension-type headache. Cephalalgia. 2011;31(5):523\u0026ndash;35.\u003c/li\u003e\n \u003cli\u003eSzulc P, et al. The relationship between cervical spine and masticatory system: a review of the literature. Biomed Res Int. 2020;2020:9215136.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable 1: Demographic characteristics of the participants\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" align=\"\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eCharacteristics\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003eGroup\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eMean \u0026plusmn; SD\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003eAge\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003eCMNP (\u003cem\u003en =26)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e24.2 \u0026plusmn; 3.01\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003eHealthy\u003cem\u003e\u0026nbsp;(n=26)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e24.3 \u0026plusmn; 3.09\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"4\" valign=\"top\"\u003e\n \u003cp\u003eGender\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003eCMNP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eMales (n= 17)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eFemales (n = 9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003eHealthy\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eMales (n = 17)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eFemales (n = 9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cem\u003eCMNP \u0026ndash; Chronic mechanical neck pain individuals\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eHealthy \u0026ndash; Healthy individuals without neck pain\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003en \u0026ndash; number of participants\u003c/em\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eTable 2. Between-group comparisons (CMNP vs. Controls)\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"611\" class=\"fr-table-selection-hover\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 611px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMechanical properties of the muscles and their associated fascia\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eParameter\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e95% CI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEffect Size (d)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 611px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFrequency (Hz)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eTemporalis (Rt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e-2.90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-8.4, 3]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.332\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.16\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTemporalis (Lt)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-7.06\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e[-11.4, -2.9]\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.001*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.53*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMasseter (Rt)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.80\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e[0.1, 1.5]\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.035*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.35*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eMasseter (Lt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e0.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-0.3, 1]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.206\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.21\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eSCM (Rt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e0.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-0.2, 0.9]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.190\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.21\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eSCM (Lt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e~0.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-0.5, 0.6]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.949\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.01\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eUT (Rt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e0.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-0.3, 1.3]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.241\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.19\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eUT (Lt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e0.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-0.2, 1.3]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.119\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.25\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 611px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eStiffness (N/m)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eTemporalis (Rt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e-176.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-459, 80]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.185\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.22\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTemporalis (Lt)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-252.51\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e[-447, -57]\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.01*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.39*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMasseter (Rt)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e30.00\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e[2, 59]\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.03*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.33*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eMasseter (Lt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e7.16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-15, 32]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.647\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.08\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eSCM (Rt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e-3.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-19, 14]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.694\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eSCM (Lt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e-13.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-29, 7]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.220\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.20\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eUT (Rt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e2.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-20, 27]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.819\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.04\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eUT (Lt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e6.14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-21, 30]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.641\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.08\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 611px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eLog Decrement (Elasticity)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eTemporalis (Rt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e0.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-0.08, 0.30]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.256\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.18\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eTemporalis (Lt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e0.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-0.13, 0.18]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.687\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eMasseter (Rt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e0.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-0.02, 0.21]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.080\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.28\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eSCM (Rt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e-0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-0.20, 0.05]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.260\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.18\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eSCM (Lt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e-0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-0.13, 0.12]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.949\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.01\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eUT (Rt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e0.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-0.07, 0.11]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.763\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eUT (Lt)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e0.02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e[-0.07, 0.11]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.628\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 611px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOculomotor control \u0026ndash; SPNTT Gains\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVertical Downward Gain\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;(Rt Eye, Rt torsion)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.13\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e[0.02, 0.26]\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.03*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.35*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 191px;\"\u003e\n \u003cp\u003eHorizontal \u0026amp; other Vertical Gains (all directions)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u0026gt; 0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u0026lt; 0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eRt = Right, Lt = Left, CMNP-Chronic mechanical neck pain, SCM-Sternocleidomastoid, UT-Upper trapezius, SPNTT-Smooth pursuit neck torsion test; ns-not significant.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-musculoskeletal-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmsd","sideBox":"Learn more about [BMC Musculoskeletal Disorders](http://bmcmusculoskeletdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://author-welcome.nature.com/12891","title":"BMC Musculoskeletal Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Cervical pain, Connective tissue, Eye movements, Muscle stiffness, Visual disorders","lastPublishedDoi":"10.21203/rs.3.rs-7013908/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7013908/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cem\u003e\u003cstrong\u003eBackground\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e:\u003c/em\u003e\u003cstrong\u003e \u003c/strong\u003eChronic mechanical neck pain (CMNP) is often associated with visual impairments, headaches, and temporomandibular dysfunctions. The plethora of symptoms associated with neck pain results from the densification of the deep cervical fascia and its myofascial continuum. Although there exists an anatomical myofascial link between the neck, the head, and Tenon's capsule of the eye, their functional interrelationship remains unclear. This study compares the mechanical properties of masticatory and neck muscles and oculomotor control in individuals with and without CMNP.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eMethods\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e:\u003c/em\u003e A comparative cross-sectional study was performed involving 26 participants with chronic mechanical neck pain and 26 healthy individuals matched for age and gender, aged between 18 and 45 years. The outcome includes the biomechanical properties (stiffness, frequency, and decrement) of the head and neck muscles using myotonpro and the oculomotor control, evaluated through the smooth pursuit neck torsion (SPNT) test using videonystagmography.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eResults\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e:\u003c/em\u003e\u003cstrong\u003e \u003c/strong\u003eIndependent t-test revealed that there were statistically significant differences in the frequency Hz (p= 0.001) and stiffness N/m (p= 0.01) of the temporalis and masseter muscles, suggesting increased tonus and stiffness in the neck pain group compared to the healthy individuals.\u003cstrong\u003e \u003c/strong\u003eIn addition, a significant reduction in vertical downward gain of the right eye during right trunk torsion was observed in the CMNP group (mean difference = 0.13, p = 0.032, effect size = 0.35), whereas vertical upward gains and horizontal gains showed no statistically significant differences between participants with and without neck pain.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eConclusion\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e: \u003c/em\u003eIndividuals with CMNP demonstrate modifications in the mechanical properties of masticatory muscles, along with noticeable impairments in oculomotor control. The findings underscore the importance of implementing comprehensive assessment and management strategies that specifically address both myofascial and sensorimotor dysfunctions in CMNP.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eTrial registration:\u003c/strong\u003e\u003c/em\u003eThe trial registration number for this study is IEC 828-2021. The trial was registered with the Clinical Trials Registry, India CTRI/2022/02/040383. Registration date: 17/02/2022.\u003c/p\u003e","manuscriptTitle":"Comparison of mechanical properties of masticatory muscles and oculomotor control in individuals with and without chronic mechanical neck pain: A cross- sectional study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-09 14:38:50","doi":"10.21203/rs.3.rs-7013908/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-09-24T14:09:37+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-08-29T10:14:08+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-08-19T02:44:25+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-08-12T11:15:33+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"311661432090074190701512347226735093549","date":"2025-08-02T07:06:28+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"166015663754743450037479272881457532887","date":"2025-07-31T13:13:41+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-31T05:54:48+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"166923373435749985093028820310665017364","date":"2025-07-30T18:17:35+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"72810105165465837073198191170555920054","date":"2025-07-30T17:04:20+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-07-30T17:00:28+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-07-05T08:34:58+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-07-05T08:32:47+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Musculoskeletal Disorders","date":"2025-06-30T19:59:12+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-musculoskeletal-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmsd","sideBox":"Learn more about [BMC Musculoskeletal Disorders](http://bmcmusculoskeletdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://author-welcome.nature.com/12891","title":"BMC Musculoskeletal Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"17cfee24-66c7-46d6-8b95-796598707625","owner":[],"postedDate":"August 9th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-01-16T17:08:25+00:00","versionOfRecord":[],"versionCreatedAt":"2025-08-09 14:38:50","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7013908","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7013908","identity":"rs-7013908","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}