Patients with chronic neck pain demonstrate altered patterns of muscle activation during performance of a functional upper limb task

The influence of chair recline and head and neck position on upper trapezius activity and stiffness during seated computer work

Increasing chair recline during seated computer work may reduce the load placed on the upper trapezius (UT), a common location of pain for those with idiopathic chronic neck pain. This study determined the effect of increasing chair recline on UT stiffness and muscle activity during computer work in people with and without idiopathic chronic neck pain. Surface electromyography and ultrasound shear wave elastography were collected from three subdivisions of the UT in 15 individuals with idiopathic chronic neck pain and 15 sex-matched healthy controls. Participants sat in a standardized computer-work setup while chair recline (0°, 25°, 45°) and head and neck position (self-selected, neutral, flexed) were systematically adjusted and maintained for 2.5-min intervals. Repeated-measures ANOVAs were completed for each sex, muscle, and data type, with group (chronic neck pain, control), chair recline (0°,25°,45°), head and neck position (self-selected, flexed, neutral), and side of collected data (dominant, non-dominant) as fixed factors. Men with idiopathic chronic neck pain demonstrated greater UT stiffness in the cranial subdivision when compared to healthy men. Additionally, the 25° and 45° recline levels increased the stiffness of men's dominant UT compared to men's non-dominant UT. Women's UT was more affected by head and neck position, and a neutral head and neck position resulted in lower UT activation, but higher UT stiffness for the cranial subdivision and midway between C-7 and the acromion process. Overall, our findings suggest that the commonly suggested neutral position may not be a beneficial prompt when positioning someone during seated computer work.

The role of the deep cervical extensor muscles in multi-directional isometric neck strength

Clinical management of whiplash-associated disorders is challenging and often unsuccessful, with over a third of whiplash injuries progressing to chronic neck pain. Previous imaging studies have identified muscle fat infiltration, indicative of muscle weakness, in the deep cervical extensor muscles (multifidus and semispinalis cervicis). Yet, kinematic and muscle redundancy prevent the direct assessment of individual neck muscle strength, making it difficult to determine the role of these muscles in motor dysfunction. The purpose of this study was to determine the effects of deep cervical extensor muscle weakness on multi-directional neck strength and muscle activation patterns. Maximum isometric forces and associated muscle activation patterns were computed in 25 test directions using a 3-joint, 24-muscle musculoskeletal model of the head and neck. The computational approach accounts for differential torques about the upper and lower cervical spine. To facilitate clinical translation, the test directions were selected based on locations where resistance could realistically be applied to the head during clinical strength assessments. Simulation results reveal that the deep cervical extensor muscles are active and contribute to neck strength in directions with an extension component. Weakness of this muscle group leads to complex compensatory muscle activation patterns characterized primarily by increased activation of the superficial extensors and deep upper cervical flexors, and decreased activation of the deep upper cervical extensors. These results provide a biomechanistic explanation for movement dysfunction that can be used to develop targeted diagnostics and treatments for chronic neck pain in whiplash-associated disorders.

McKenzie neck exercise versus cranio-cervical flexion exercise on strength and endurance of deep neck flexor muscles, pain, disability, and craniovertebral angle in individuals with chronic neck pain: a randomized clinical trial

PURPOSE

To compare the effectiveness of McKenzie neck exercise and cranio-cervical flexion (CCF) exercise on strength and endurance of deep neck flexor (DNF) muscles, pain, disability, and craniovertebral angle (CVA) in individuals with chronic neck pain.

METHODS

Forty individuals with chronic neck pain were randomly allocated to the McKenzie neck or CCF exercise group. Each group performed exercises at home daily. The strength and endurance of DNF muscles were measured at baseline, immediately after the first exercise session, and each week follow-up for six weeks. Average pain over the past week was measured at baseline and each week follow-up for six weeks. Disability and CVA were measured at baseline and the end of six weeks.

RESULTS

At six weeks, both groups exhibited significant improvements across all outcome variables (p < 0.001) but there were no differences between groups (p > 0.05). The significant difference from baseline in the strength of DNF muscles was observed as early as the second week of each intervention (p ≤ 0.001). The significant difference from baseline in the endurance of DNF muscles was observed as early as the first week in the CCF exercise group (p < 0.05) and the second week in the McKenzie neck exercise group (p < 0.05). A significant decrease in pain intensity from baseline was observed after the first week in the McKenzie neck exercise group (p < 0.001) while it was after the second week in the CCF exercise group (p < 0.05).

CONCLUSION

Both the McKenzie neck exercise and CCF exercise produced similar effects in enhancing the strength and endurance of the DNF muscles, decreasing pain, alleviating neck disability, and improving the CVA.

Ultrasonographic measurement indicated patients with chronic neck pain had reduced diaphragm thickness and mobility along with declined respiratory functions

BACKGROUND

Chronic neck pain (CNP) is a prevalent musculoskeletal condition including notable impairments in respiratory function. The diaphragm, serving dual roles in respiration and spinal stability, is intricately linked to the cervical spine through fascial, neurophysiological, and biomechanical connections. However, to date, none has investigated the diaphragm function in patients with CNP.

OBJECTIVES

To investigate the diaphragm function, respiratory muscle strength, and pulmonary function in patients with CNP. In addition, their associations were also examined.

DESIGN

A case-control study.

METHODS

A total of 54 participants were recruited including 25 patients with CNP (CNP group) and 29 healthy adults (CON group). Pulmonary function including forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1), and respiratory muscle strength represented by maximal inspiratory (MIP) and maximal expiratory pressure (MEP), as well as diaphragm function including ultrasonographic measures of mobility and thickness changes during maximal inspiration and expiration were assessed in all participants. Additionally, the intensity of pain and disability were evaluated using a Visual Analog Scale and Neck Disability Index only in patients with CNP.

RESULTS

Significant reductions of the FVC, FEV1, MIP, and MEP were found in the CNP group compared to the CON group (p < 0.05). The diaphragm mobility and thickness changes were also significantly decreased in the CNP group than the CON group with medium effect sizes (p < 0.05). Only diaphragm thickness change was positively correlated with FVC, FEV1, and MEP in patients with CNP. Furthermore, MEP showed the strongest contribution to diaphragm thickness change based on the regression analysis.

CONCLUSIONS

Impaired diaphragm function, respiratory muscle strength, and pulmonary function were observed in patients with CNP. Patients with smaller diaphragm thickness change had poorer pulmonary function and reduced maximal expiratory muscle strength. Diaphragm assessment and intervention may be considered in CNP management.

The top 100 highly cited articles on neck pain: A bibliometric analysis

Objective

Neck pain has emerged as a significant public health concern. This study is to unveil the present state of neck pain research, thereby furnishing invaluable insights for prospective research endeavours and clinical applications.

Methods

The study was initiated by searching the Web of Science Core Collection database, focusing on "neck pain". From the amassed results, the top 100 most cited references were imported into CiteSpace and VOSviewer, enabling a rigorous bibliometric analysis. To ensure precision, synonymous terms conveying similar meanings were harmonized. The bibliometric study encompassed countries, research institutions, authors, journals, and keyword analysis.

Results

The investigation centered on a curated compilation of 100 articles, disseminated across a diverse array of 36 scholarly journals. These seminal articles originated from 24 distinct countries, reflecting contributions from a wide spectrum of 188 research institutions. Impressively, a collaborative effort involving 385 authors emerged. Noteworthy core research countries included the United States and Australia, with the University of Queensland and the University of Toronto asserting notable influence. Prolific authors such as J. David Cassidy and Pierre Cote garnered attention. Present research endeavours pivot around the incidence of neck pain, the identification of risk factors, the efficacy evaluation of treatment modalities, and a pronounced focus on high-quality randomized controlled trials and systematic reviews.

Conclusion

The study shines a light on key research countries, influential institutions, prominent authors, and prevalent trends, effectively contributing to comprehending the knowledge landscape and research dynamics in the field of neck pain.

Differences of diaphragmatic muscle contraction between female patients with chronic neck pain and asymptomatic controls: A case-control study based on ultrasonography

BACKGROUND

Recent systematic reviews and meta-analyses show that individuals with chronic neck pain (CNP) have altered respiratory muscle strength and abnormal respiratory mechanics. However, no study has investigated the diaphragmatic function in individuals with CNP compared to asymptomatic peers.

OBJECTIVES

This study aimed to compare the respiratory muscle strength and diaphragmatic function between patients with CNP and asymptomatic controls.

DESIGN

Observational, case-control study.

METHODS

A total of 25 women with CNP and 23 asymptomatic controls participated in this case-control study. The visual analog scale and neck disability index were used to assess the pain and disability characteristics of the CNP group. Maximum inspiratory and expiratory pressures (MIP and MEP) were measured to determine respiratory muscle strengths. The diaphragmatic function (muscle thickness in deep inspiration, Tins; and at the end of calm expiration, Texp; muscle thickness change, ΔT; contraction ratio, CR) were evaluated by two-dimensional ultrasonography.

RESULTS

The MIP (p = 0.001, d = 1.11), ΔT (p = 0.033, d = 0.63), and CR (p = 0.012, d = 0.75) of the diaphragm were found significantly reduced in the CNP group compared to asymptomatic controls whilst MEP, Tins, and Texp of the diaphragm were similar between study groups (p > 0.05). The intensity of neck pain was moderately correlated with MIP (r = -0.48), Tins (r = -0.46), and ΔT (r = -0.42) while NDI (r = -0.42) had a moderate correlation with Tins (p < 0.05).

CONCLUSION

The present findings revealed that women with CNP have altered diaphragmatic function. Thus, screening and targeting diaphragm may improve the rehabilitation process in CNP. However, further experimental studies regarding the efficacy of breathing exercise approaches are needed.

Network analyses reveal the interaction between physical features, fear of movement and neck pain and disability in people with acute and chronic whiplash-associated disorders

BACKGROUND AND OBJECTIVE

A network analysis can be used to quantitatively assess and graphically describe multiple interactions. This study applied network analyses to determine the interaction between physical and pain-related factors and fear of movement in people with whiplash-associated disorders (WAD) during periods of acute and chronic pain.

METHODS

Physical measurements, including pressure pain-thresholds (PPT) over neural structures, cervical range of motion, neck flexor and extensor endurance and the cranio-cervical flexion test (CCFT), in addition to subjective reports including the Tampa Scale of Kinesiophobia (TSK-11), Neck Disability Index (NDI) and neck pain and headache intensity, were assessed at baseline in 47 participants with acute WAD. TSK-11, NDI and pain intensity were assessed for the same participants 6 months later (n = 45). Two network analyses were conducted to estimate the associations between features at baseline and at 6 months and their centrality indices.

RESULTS

Both network analyses revealed that the greatest weight indices were found for NDI and CCFT at baseline and for neck pain and headache intensity and NDI and TSK-11 at both time points. Associations were also found betweeen cervical muscle endurance and neck pain intensity in the acute phase. Cervical muscle endurance assesssed during the acute phase was also associated with NDI after 6 months - whereas PPT measured at baseline was associsated with headache intensity after 6 months.

CONCLUSION

The strongest associations were found for headache and neck pain intensity and neck disability and fear of movement, both during acute pain and when mesured 6 months later. The extent of neck endurance and measures of PPT at baseline may be associated with neck disability and headache, respectively, 6 months after a whiplash injury.

SIGNIFICANCE

Through two network analyses, we evaluated the interaction between pain-related factors, fear of movement, neck disability and physical factors in people who had experienced a whiplash injury. We demonstrated that physical factors may be involved in the maintenance and development of chronic pain after a whiplash injury. Nevertheless, the strongest associations were found for headache and neck pain intensity and neck disability and fear of movement, both during acute and chronic phases.

Exercise therapy including the cervical extensor muscles in individuals with neck pain: A systematic review

OBJECTIVE

To review the use (dosage parameters and combination with other therapeutic interventions) of cervical extensor muscle exercises and their effect on pain, disability (primary outcomes), range of motion, endurance and strength (secondary outcomes) in people with neck pain.

DATA SOURCES

An extensive literature search was conducted through MEDLINE (Ovid), Scopus (Elsevier) and Physiotherapy Evidence Database (PEDro) up to May 2023. The reference lists of all included studies and relevant reviews were screened for additional studies.

REVIEW METHODS

Randomised controlled trials reporting the use of cervical extensor muscle exercises (alone or combined) applied to adults with idiopathic or traumatic neck pain were included. Study selection, data extraction and critical appraisal (PEDro assessment scale) were performed by two blinded reviewers. Data extraction included dosage parameters, other modalities combined with these exercises and outcomes.

RESULTS

Thirty-five randomised controlled trails (eight of which were complementary analyses) with 2409 participants fulfilled the inclusion criteria. Twenty-six were of moderate to high quality. In most studies, cervical extensor muscle exercises were combined with various other therapeutic modalities and applied at different dosages. Only two studies (one high and one low quality) specifically assessed their effectiveness. The high-quality study showed significant improvements in neck pain and disability, pressure point threshold and neck mobility after both low load and high load training for 6 weeks.

CONCLUSION

The results suggest cervical extensor muscle exercises may reduce neck pain and disability; however firm conclusions cannot be drawn because of the few studies that addressed this question and the heterogeneity of the dosage parameters.

Neck Health Metrics and Quality of Life: A Comparative Study in Bike Drivers with and without Neck Pain

Purpose

Neck pain is a prevalent musculoskeletal issue among bike drivers, often resulting from extended static postures, repetitive head movements, and exposure to vibrations. This study aims to assess the connection between cervical ROM, neck proprioception, CVA, and QOL in bike drivers with neck pain compared to those without neck pain so that the targeted interventions can be developed to enhance their well-being.

Methods

A cross-sectional study involving 100 bike drivers aged 20-50 years was conducted, split into two groups: those with neck pain (n=50) and those without neck pain (n=50). Cervical ROM was measured using a smartphone, neck proprioception was assessed through a head repositioning test, and CVA was determined using lateral-view photographs with a plumb line. The Short Form-36 (SF-36) questionnaire was employed to evaluate QOL. Data analysis was conducted using independent t-tests and Pearson's correlation coefficient.

Results

Bike drivers with neck pain exhibited significantly reduced cervical ROM (p-value=<0.001), impaired neck proprioception (p-value=<0.001), and decreased CVA (p-value=<0.001) compared to their counterparts without neck pain. A strong negative correlation was found between neck pain and QOL, with lower scores in all eight domains of the SF-36. Cervical ROM, neck proprioception, and CVA showed moderate correlations with various QOL domains (p-value=<0.05).

Conclusion

Neck pain in bike drivers is linked to decrease cervical ROM, compromised neck proprioception, and reduced CVA. These factors correlate with a lower quality of life, both physical and mental domains. Interventions addressing these aspects may enhance the quality of life for bike drivers experiencing neck pain.

Summarizing the effects of different exercise types in chronic neck pain - a systematic review and meta-analysis of systematic reviews

BACKGROUND

To date, no consensus exists as to whether one exercise type is more effective than another in chronic neck pain. This systematic review and meta-analysis of systematic reviews aimed to summarize the literature on the effect of various exercise types used in chronic neck pain and to assess the certainty of the evidence.

METHODS

We searched the databases Ovid MEDLINE, Embase, Cochrane Library, SportDiscus, and Web of Science (Core Collection) for systematic reviews and meta-analyses on adults between 18 and 70 years with chronic neck pain lasting ≥ 12 weeks which investigated the effects of exercises on pain and disability. The included reviews were grouped into motor control exercise (MCE), Pilates exercises, resistance training, traditional Chinese exercise (TCE), and yoga. Study quality was assessed with AMSTAR-2 and the level of certainty for the effects of the exercise through GRADE. A narrative analysis of the results was performed and in addition, meta-analyses when feasible.

RESULTS

Our database search resulted in 1,794 systematic reviews. We included 25 systematic reviews and meta-analyses including 17,321 participants (overlap not accounted for). The quality of the included reviews ranged from critically low to low (n = 13) to moderate to high (n = 12). We found low to high certainty of evidence that MCE, Pilates exercises, resistance training, TCE, and yoga have short-term positive effects on pain and that all exercise types except resistance training, show positive effects on disability compared to non-exercise controls. We found low to moderate certainty of evidence for conflicting results on pain and disability when the exercise types were compared to other exercise interventions in the short-term as well as in intermediate/long-term apart for yoga, as no long-term results were available.

CONCLUSION

Overall, our findings show low to high certainty of evidence for positive effects on pain and disability of the various exercise types used in chronic neck pain compared to non-exercise interventions, at least in the short-term. Based on our results, no optimal exercise intervention for patients with chronic neck pain can be recommended, since no large differences between the exercise types were shown here. Because the quality of the included systematic reviews varied greatly, future systematic reviews need to increase their methodological quality.

TRIAL REGISTRATION

Prospero CRD42022336014.

Effects of Yi Jin Jing on juvenile cervical spondylopathy in China: A parallel, randomized, assessor-blinded clinical trial

Background

Cervical spondylopathy is a common musculo-articular disorder, multiple exercises are recommended. Chinese fitness exercises are prevalent and used to treat various diseases.

Aim

To explore the efficacy of Chinese fitness exercise Yi Jin Jing exercise in intervening the cervical spondylopathy in adolescents.

Patients and Methods

The study was conducted in 60 adolescent patients with cervical spondylopathy, with 30 patients in each group.

Methods

The study was conducted in 60 adolescent patients with cervical spondylopathy, with 30 patients in each group. The observation group was required to take Yi Jin Jing exercise, and the control group took the brisk walking exercise. The first week was the preparatory period for the patients, and then the participants were required to do exercises three times a week for at least 30 minutes in the later 3 weeks. Before and after treatment, Neck Disability Index (NDI) scores, pain visual analog scale (VAS) scores, and cervical curvature in both groups were observed, and the incidence of adverse events in both groups was recorded during the trial.

Results

The NDI and VAS scores in both groups statistically decreased after intervention and mildly increased at follow-up, while the reduction in scores of the Yi Jin Jing group was more significant. Cervical curvature in both groups improved on day 28 compared to day 0. There were no adverse reactions during the evaluation period.

Conclusion

The Chinese health-care qigong Yi Jin Jing exercise is more effective than brisk walking in improving the cervical range of motion and relieving pain in adolescents with cervical spondylopathy. Trial registration/Protocol registration: Clinical Trial Registry (ChiCTR2000030723).

Short-term outcomes after primary reverse total shoulder arthroplasty in patients with cervical spine pathology or previous cervical spine surgery compared to those without

BACKGROUND

Cervical spine (c-spine) and shoulder pathology have been known to cause similar symptoms and often co-exist, making an accurate diagnosis difficult, especially in an elderly population. Reverse total shoulder arthroplasty (rTSA) has been shown to decrease pain and improve quality of life when shoulder pathology is the source of pain and disability. The purpose of this study was to identify the prevalence of c-spine pathology in a cohort of patients who underwent rTSA and to compare postoperative outcome scores to a cohort without c-spine pathology.

METHODS

A retrospective review was performed utilizing a single institution's operative records of primary rTSAs. Radiology reports, imaging, and operative reports were reviewed, and presence of any c-spine pathology or previous surgery were recorded. Additionally, postoperative outcome scores (American Shoulder and Elbow Surgeons [ASES], Constant Score, University of California, Los Angeles [UCLA], and Simple Shoulder Test [SST]) were evaluated at >2 years post-rTSA.

RESULTS

A total of 438 primary rTSA cases were evaluated. Of these, 143 (32.6%) had documentation of prior c-spine pathology and/or history of previous c-spine surgery. After applying further exclusion criteria, a total of 50 patients with c-spine pathology and 108 patients without c-spine pathology were found to have complete medical records and postoperative outcome scores to allow comparison between groups. Patients without c-spine pathology were found to have statistically higher postoperative UCLA, ASES, and SST scores when compared to patients with c-spine pathology. Patients without c-spine pathology also demonstrated a significant improvement in the difference between their postoperative and preoperative UCLA and ASES scores.

CONCLUSION

This study demonstrated a high prevalence of c-spine pathology (32.6%) in a cohort of patients who underwent primary rTSA. Additionally, short-term outcome scores of patients undergoing rTSA with concomitant c-spine pathology are significantly lower than those of patients without a history of c-spine pathology.

Analysis of abnormal muscle activities in patients with loss of cervical lordosis: a cross-sectional study

BACKGROUND

This study aimed to detect the differences in cervical muscle activation patterns in people with versus without cervical lordosis and explore the possible mechanism of cervical pain originating therein.

METHODS

This cross-sectional design included 39 participants without and 18 with normal cervical lordosis. Muscular activation was measured for 5 s in both groups using surface electromyography. Subsequently, the root mean square (RMS) of muscle amplitude was obtained at the bilateral splenius capitis, upper and lower parts of the splenius cervicis, upper and lower parts of the semispinalis cervicis, sternocleidomastoid, upper trapezius, and rhomboid muscles in five cervical positions: 0° (resting), 30° of flexion, 30° of extension, 60° of extension, and upon a 1-kg load on the head in a resting posture.

RESULTS

The RMS values of the upper trapezius muscle at all postures and the rhomboid muscles at 60° of extension were significantly lower in the loss of lordosis than control group. Comparing the RMS ratio of each posture to the resting position, the ratio of the upper trapezius at flexion was significantly higher and that of the rhomboids at 60° of extension and upon loading was significantly lower in the loss of lordosis than control group. Moreover, the pattern changes in the RMS values according to posture showed a similar shape in these two muscles, and lower in the loss of lordosis than the normal group.

CONCLUSIONS

The loss of normal cervical alignment may correlate with predisposed conditions such as reduced muscle activation of the trapezius and rhomboid muscle, and may also provoke over-firing of the upper trapezius muscle, possibly increasing neck musculoskeletal pain.

TRIAL REGISTRATION

CLINICALTRIALS

gov, registration number: NCT03710785.

Investigation of Real-Time Diagnostic Ultrasound as a Means of Biofeedback Training in Transversus Abdominus Re-Education of Patients with Non-Specific Low Back Pain: A Prospective Randomized Controlled Pilot Study

Background: It is believed that ultrasound-guided imaging of activation/contraction of the deep abdominal muscles (such as transervsus abdominis) is useful for assisting deep muscle re-education, which is often dysfunctional in non-specific low back pain (NSLBP). Thus, this pilot study aimed to evaluate the use of real-time ultrasound (US) as a feedback device for transverse abdominis (TrA) activation/contraction during an exercise program in chronic NSLBP patients. Methods: Twenty-three chronic NSLBP patients were recruited and randomly assigned to a US-guided (n = 12, 8 women, 47.6 ± 2.55 years) or control group (n = 11, 9 women, 46.9 ± 4.29 years). The same motor control-based exercise program was applied to both groups. All patients received physiotherapy twice per week for seven weeks. Outcome measures, tested at baseline and post-intervention, included Numeric Pain Rating Scale, TrA activation level (measured through a pressure biofeedback unit-based developed protocol), seven established motor control tests, Roland-Morris Disability Questionnaire and Hospital Anxiety and Depression Scale. Results: For each group, all outcome variables yielded statistical differences post-intervention (p < 0.05), indicating significant improvements. However, there were no significant group x time interactions for any of the outcomes (p > 0.05), thus, indicating no superiority of the US-guided group over the control. Conclusions: The addition of US as a visual feedback device for TrA re-education during a motor control exercise program was not proven superior to traditional physiotherapy.

A Cross-Sectional Study on Mediating Effect of Chronic Pain on the Relationship between Cervical Proprioception and Functional Balance in Elderly Individuals with Chronic Neck Pain: Mediation Analysis Study

(1) Background: Cervical proprioception maintains head orientation in space and contributes to maintaining bodily balance. Evaluating cervical proprioception in elderly individuals with chronic neck pain (CNP) and understanding how pain intensity mediates the relationship between proprioception and functional balance helps formulate treatment strategies for this population. The objectives of this study are to (a) compare the cervical proprioception and functional balance between CNP and asymptomatic, (b) investigate the relationship between cervical proprioception and functional balance ability in CNP individuals and (c) mediation effect of chronic pain on the relationship between cervical proprioception and functional balance tests (2) Methods: This cross-sectional comparative study recruited 60 elderly individuals with a diagnosis of CNP (mean age: 66.40 years) and 60 asymptomatic (mean age: 66.42 years). The cervical proprioception is measured using the target head repositing technique. The subjects were asked to close their eyes and reposition their head actively to the target position from the neutral position, and the reposition accuracy is estimated as joint position errors (JPE) in degrees. The cervical proprioception was measured in the directions of flexion, extension, and left and right rotation. The functional balance was assessed using the berg balance test (BBS) score and timed-up-and-go (TUG) test in seconds. (3) Results: The elderly individuals with CNP had increased cervical JPE compared to the asymptomatic group (p < 0.001) in all the directions tested, indicating that cervical proprioception is impaired in CNP patients. Moreover, the CNP individual functional balance is significantly impaired (p < 0.001) compared to asymptomatic. The BBS test scores were lower, and the TUG scores were higher in the CNP group. In CNP individuals, the cervical JPE showed a significant correlation with the BBS test scores (r = -0.672 to -0.732, p < 0.001) and TUG scores (r = 0.328 to -0.414, p < 0.001). (4) Conclusions: Cervical proprioception and functional balance are impaired in elderly individuals with CNP. Physical therapists and rehabilitation professionals may consider these factors during the evaluation and development of treatment strategies in elderly adults with CNP.

Symmetry of the Neck Muscles' Activity in the Electromyography Signal during Basic Motion Patterns

The activity of muscles during motion in one direction should be symmetrical when compared to the activity of the contralateral muscles during motion in the opposite direction, while symmetrical movements should result in symmetrical muscle activation. The literature lacks data on the symmetry of neck muscle activation. Therefore, this study aimed to analyse the activity of the upper trapezius (UT) and sternocleidomastoid (SCM) muscles at rest and during basic motions of the neck and to determine the symmetry of the muscle activation. Surface electromyography (sEMG) was collected from UT and SCM bilaterally during rest, maximum voluntary contraction (MVC) and six functional movements from 18 participants. The muscle activity was related to the MVC, and the Symmetry Index was calculated. The muscle activity at rest was 23.74% and 27.88% higher on the left side than on the right side for the UT and SCM, respectively. The highest asymmetries during motion were for the SCM for the right arc movement (116%) and for the UT in the lower arc movement (55%). The lowest asymmetry was recorded for extension-flexion movement for both muscles. It was concluded that this movement can be useful for assessing the symmetry of neck muscles' activation. Further studies are required to verify the above-presented results, determine muscle activation patterns and compare healthy people to patients with neck pain.

Mediation Effect of Kinesiophobia on the Relationship between Cervical Joint Position Sense and Limits of Stability in Individuals with Fibromyalgia Syndrome: A Cross-Sectional Study Using Mediation Analysis

(1) Background: Individuals with fibromyalgia syndrome (FMS) may experience proprioceptive and balance impairments. Kinesiophobia is a factor that can mediate the relationship between cervical joint position sense (JPS) and limits of stability. The objectives of this study were to (1) compare the cervical JPS and limits of stability between FMS and asymptomatic individuals, (2) assess the relationship between cervical JPS and limits of stability, and (3) assess the mediation effect of kinesiophobia on the relationship between cervical JPS and limits of stability in FMS individuals. (2) Methods: In this comparative cross-sectional study, 100 individuals with FMS and 100 asymptomatic individuals were recruited. Cervical JPS was assessed using a cervical range of motion device, limits of stability (reaction time, maximum excursion, and direction control) were assessed using dynamic posturography, and FMS individuals' kinesiophobia was assessed using the Tampa scale of kinesiophobia (TSK). Comparison, correlation, and mediation analyses were performed. (3) Results: The magnitude of the mean cervical joint position error (JPE) was significantly larger in FMS individuals (p < 0.001) compared to the asymptomatic individuals. The limits of the stability test showed that FMS individuals had a longer reaction time (F = 128.74) and reduced maximum excursion (F = 976.75) and direction control (F = 396.49) compared to the asymptomatic individuals. Cervical JPE showed statistically significant moderate-to-strong correlations with reaction time (r = 0.56 to 0.64, p < 0.001), maximum excursion (r = -0.71 to -0.74, p < 0.001), and direction control (r = -0.66 to -0.68, p < 0.001) parameters of the limits of the stability test. (4) Conclusions: Cervical JPS and limits of stability were impaired in FMS individuals, and the cervical JPS showed a strong relationship with limits of stability variables. Moreover, kinesiophobia mediated the relationship between JPS and limits of stability. These factors may be taken into consideration when evaluating and developing treatment strategies for FMS patients.

Muscle strength, balance and upper extremity function are not predictors of cervical proprioception in healthy young subjects

Purpose/Aim: The aim of this study is to examine the relationship between cervical proprioception sense and balance, hand grip strength, cervical region muscle strength and upper extremity functionality in healthy young subjects.Methods: A total of 200 people with a mean age of 20.8 ± 1.8 participated in the study. Cervical proprioception sense of the participants was evaluated with Cervical Joint Position Error Test (CJPET), balance with Biodex Stability System, hand grip strength with hand dynamometer, and upper extremity functionality with Perdue Pegboard test. The relationship of variables with cervical proprioception was evaluated with Pearson Correlation analysis.Results: According to this study results, there was no significant relationship between CJPET (extension, left rotation, right rotation) and sub-parameters of dynamic balance (anteroposterior, mediolateral, overall), cervical muscle strength and hand grip strength (p > 0.05). There was a significant correlation between CJPET flexion and static balance variables (p < 0.05).Conclusion: According to this study, there is no relationship between cervical proprioception and balance, hand grip muscle strength, cervical region muscle strength and upper extremity functionality in healthy young subjects.

Axioscapular and neck extensor muscle behavior during isometric shoulder exertions in patients with nonspecific neck pain with and without a scapular downward rotation posture

BACKGROUND

A common observation in persons with neck pain is scapular downward rotation (SDR) with altered muscle behavior. Evidence of changes in axioscapular muscles in neck pain patients remains inconclusive, which may reflect population heterogeneity in previous studies.

RESEARCH QUESTION

Are there differences in behavior of the axioscapular (upper trapezius: UT, lower trapezius: LT and serratus anterior: SA) and neck extensor (NE) muscles during isometric shoulder tasks in patients with neck pain with SDR, patients with no scapular dysfunction and healthy controls?

METHODS

Sixty participants with nonspecific neck pain (30 with SDR and 30 without scapular dysfunction) and 30 controls were recruited. Electromyographic signals were recorded unilaterally from the UT, LT, SA and NE during different isometric shoulder tasks (30° flexion, 30°abduction and 30°external rotation) at 20%, 50% and 100% maximal voluntary contraction (MVC). Activity of UT, LT, SA and NE was normalized with respect to reference contractions. The UT/LT, UT/SA and LT/SA ratios were calculated for each task.

RESULTS

The neck pain group with SDR had increased UT activity in 30°flexion (20%MVC) and 30°abduction (20% and 50%MVC) compared to the neck pain and control groups without scapular dysfunction (p < 0.05). There were no between group differences in LT and SA activity (p > 0.05). The neck pain groups had greater NE activity in all tasks (p < 0.001). Finally, the neck pain group with SDR had higher UT/LT and UT/SA ratios in a few tasks at low force levels (p ≤ 0.01).

SIGNIFICANCE

Greater UT activity and UT/LT and UT/SA ratios during particularly low force isometric shoulder tasks suggest that SDR is associated with altered axioscapular motor control. Greater NE activity in both neck pain groups suggests altered motor control related to neck pain. Changes in the NE and UT behavior should be considered in management of patients with neck pain with observable SDR.

Acute effects of instrument assisted soft tissue mobilization technique on pain and joint position error in individuals with chronic neck pain: a double-blind, randomized controlled trial

PURPOSE/AIM

The aim of this study was to determine the acute effects of IASTM on cervical joint position error and pain in individuals with chronic neck pain.

METHODS

A total of 39 individuals with chronic neck pain were included in this study. Participants were randomized into three groups: Instrument-assisted soft-tissue mobilization(IASTM (n = 13), sham (n = 13), and control (n = 13). In the IASTM group, intervention was applied to the sternocleidomastoid and trapezius muscles with an application time of 45 s and a frequency of 60 beats/min. In the sham group, IASTM was applied at a 90° angle without pressure. The control group did not receive any intervention. The pain severity and joint position error(JPE) were evaluated before and after the intervention, by using the visual analogue scale and a cervical range of motion device.

RESULTS

The effects of time and treatment group on visual analogue scale(VAS) score were statistically significant (p = .001). Instrument-assisted soft-tissue mobilization was more effective in VAS score than sham and control group (p < .001). Significant improvement was found in JPE in all range of motions of the cervical region in the instrument-assisted soft-tissue mobilization group (p < .05). In the sham group, significant improvements were observed in cervical extension, left rotation, and left lateral flexion movements in JPE during each cervical spine active movement (p < .05). Instrument-assisted soft-tissue mobilization group was more effective in JPE all directions than sham and control group.

CONCLUSIONS

Instrument-assisted soft-tissue mobilization may be a useful technique in individuals with chronic neck pain. Instrument-assisted soft-tissue mobilization decreases VAS and improves JPE.

CLINICAL TRIAL REGISTRATION NUMBER

NCT04882397 (05 August 2021).

Sex-related differences in sternocleidomastoid muscle morphology in healthy young adults: A cross-sectional magnetic resonance imaging measurement study

BACKGROUND

Changes in sternocleidomastoid (SCM) muscle cross-sectional area (CSA) and volume may contribute to neck-related concussion symptoms and whiplash-associated disorders. Magnetic resonance imaging (MRI) data on healthy SCM morphology can provide information that may lead to targeted treatment protocols.

OBJECTIVES

To examine sex-related differences in MRI-based SCM CSA, SCM volume and neck area in healthy young adults, to analyze associations between measurements and participant variables and to assess inter-rater reliability for measurement quantification.

DESIGN

Cross-sectional study.

METHODS

13 males and 14 females underwent MRI scans. Slices obtained from C3-C7 were analyzed by three raters. SCM CSA at C4, total SCM volume from C3-C7 and neck area at C4 were quantified. Measurements were calculated as absolute and normalized values by body mass. Multivariable regression was used to analyze associations between normalized measurement values and participant variables. Inter-rater reliability was determined using intraclass correlation coefficients (ICC).

RESULTS

Females had significantly lower normalized overall average SCM CSA (mean difference 1.3 mm²/kg (95% CI 0.4-2.2, p = 0.006) and total SCM volume (mean difference 140.8 mm3/kg (95% CI 66.1-215.5, p < 0.001) than males. Regression models indicated female sex was associated with lower normalized overall average SCM CSA (p = 0.004) and total SCM volume (p < 0.001). Inter-rater reliability was excellent for SCM CSA (ICC_3,3 = 0.909), SCM volume (ICC_3,3 = 0.910) and neck area (ICC_3,3 = 0.995).

CONCLUSIONS

These results enhance our understanding of sex-related differences in SCM morphology and will inform future research and clinical practice related to cervical muscle injury.

Impact of adding scapular stabilization to postural correctional exercises on symptomatic forward head posture: a randomized controlled trial

BACKGROUND

One of the most overspread postural abnormalities is forward head posture (FHP) and it is described as head projection anteriorly in relation to the trunk which appears mainly in sagittal plane. Scapular stabilization exercise (SSE) is capable of restoring each of thoracic cage and head neutral optimum position by neck and shoulder muscles interactions and through controlling scapular position and movement.

AIM

This study was conducted to investigate the impact of adding scapular stabilization (SSE) to postural correctional exercises (PCE) on symptomatic FHP.

DESIGN

The pre-post single-masking (assessor) randomized experimental trial.

SETTING

Participants with postural dysfunction in form of FHP admitted to outer clinic of the Faculty of Physical Therapy.

POPULATION

Sixty participants (20 to 35 years) with symptomatic FHP and recruited from outer clinic at faculty of physical therapy.

METHODS

Participants were allocated randomly by opaque sealed envelope to two groups who are referred from an orthopedist: Group "A" received SSE and postural correction exercises, whereas Group "B" received only postural correctional exercises; treatments were performed three times/week for 10 weeks. The craniovertebral angle, pressure pain threshold, cervical flexor and extensor muscles endurance, Arabic neck disability index, upper trapezius and sternocleidomastoid muscle root mean square during rest and activity were used to evaluate the patients' pretreatment and post-treatment.

RESULTS

Within group analysis for sixty participants reported statistical significant difference between baseline and post-treatment as P value <0.05 with more refinement in stabilization exercise group.

CONCLUSIONS

Adding SSEs to PCEs is more effective method than PCEs seldom for the management of FHP patients.

CLINICAL REHABILITATION IMPACT

Both scapular stabilization and postural correction exercise increase craniovertebral angle and pressure pain threshold (PPT) and decrease muscle activity and disability. Scapular stabilization alone increase craniovertebral angle and PPT and decrease muscle activity and disability more than postural correction exercise. In addition of statistical significant difference in all variables but there were clinical change in disability only.

Fat Infiltration of Multifidus Muscle Is Correlated with Neck Disability in Patients with Non-Specific Chronic Neck Pain

Background: Chronic non-specific neck pain (CINP) is common, but the etiology remains unclear. This study aimed to examine the relationship between cervical muscle composition (cervical multifidus and longus capitis/longus colli), morphometry, range of movement, muscle function, and disability severity (Neck Disability Index) in patients with CINP. Methods: From September 2020 to July 2021, subjects underwent cervical MRI and clinical tests (cervical range of motion, cranio-cervical flexion test, neck flexor, and extensor muscle endurance). MRI analysis comprised muscle cross-sectional area, volume, and fat infiltration of multifidus and longus colli between C4 and C7 levels. Results: Twenty-five participants were included. Multiple linear regression analysis indicated that NDI was positively correlated with the volume percentage of fat infiltration of the multifidus (B = 0.496), negatively correlated with fat-free muscle volume of the multifidus normalized by subject height (B = −0.230), and accounted for 32% of the variance. There was no relationship between neck disability and longus capitis/longus colli morphology. We also found no relationship between neck disability scores, neck flexor or extensor muscle endurance, or the outcome motor control test of craniocervical flexion (p > 0.05). Conclusions: Neck disability was moderately correlated with the percentage of fat volume in the multifidus muscle and fat-free volume of the multifidus. There was no relationship between NDI scores and muscle function test outcomes or any fat or volume measures pertaining to the longus colli muscle.

Morphology and composition of the ventral neck muscles in individuals with chronic whiplash related disorders compared to matched healthy controls: a cross-sectional case-control study

BACKGROUND

OBJECTIVE: Studies of cross-sectional area (CSA) (morphology) and muscle fat infiltration (MFI) (composition) in ventral neck muscles is scarce in patients with chronic whiplash associated disorders (WAD), especially for men and those with severe WAD compared with matched healthy controls. The aim was to compare CSA and MFI of sternocleidomastoid (SCM), longus capitis (LCA) and longus colli (LCO) in patients with chronic right-sided dominant moderate (Neck Disability Index: NDI < 40) or severe WAD (NDI ≥ 40), compared to age- and sex-matched healthy controls.

METHODS

Cross-sectional case-control study with blinded investigators. Thirty-one patients with chronic WAD (17 women and 14 men, mean age 40 years) (SD 12.6, range 20-62)) and 31 age- and sex-matched healthy controls underwent magnetic resonance imaging of ventral neck muscles segmental level C4.

RESULTS

Unique to the severe group was a larger magnitude of MFI in right SCM (p = 0.02) compared with healthy controls. There was no significant difference between the groups with regards to the other muscles and measures.

CONCLUSIONS

Individuals with severe right-sided dominant WAD have a higher MFI in the right SCM compared to healthy controls. No other differences were found between the groups. The present study indicates that there are changes in the composition of muscles on the side of greatest pain.

Patient-specific numerical investigation of the correction of cervical kyphotic deformity based on a retrospective clinical case

Little research has been reported on evaluating the safety of the fixation construct in cervical kyphosis correction. In this study, we proposed a principal-strain criterion to evaluate the safety of the fixation construct and validated the modeling method against a retrospective case of anterior cervical discectomy fusion (ACDF). From C2 to T2 vertebra bodies, fixation instruments were reconstructed and positioned as per postoperative computed tomography (CT) scans. Head weight (HW) and various moments estimated from isometric strength data were imposed onto the C2. The postoperative stability of non-surgical segments, deformations surrounding the screw trajectories, and contact slipping on zygapophysial joints were analyzed. The model was validated against the reality that the patient had a good fusion and deformity correction. The ACDF restricted the range of motions (ROMs) of cervical segments and lent stability to vertebra fusion, no failure was found in the finite element (FE) model of cervical vertebrae. The deformation surrounding the screw trajectories were concentrated to the lateral sides of trajectories, recommending that the shape of the anterior cervical plate conforming to the curvature of the vertebra and screws fully inserted into vertebrae reduced the deformation concentration around the screw trajectories.

Tension-type headache and low back pain reconsidered

The natural history and clinical course of tension-type headache and non-specific low back pain are reconsidered. By closer examination, these two conditions appear to share several specific clinical features. Both are muscular pain conditions along the spine, they have a preponderance in women, they may occur spontaneously or follow a trivial traumatic incident, and they both have a high risk of chronicity. The affected muscles are tender with tender points. EMG indicates diffuse hyperactivity and abnormal activation pattern, and motor control of the affected muscles and adjacent muscle groups is discoordinated. These shared features suggest analogous pathophysiology involving the neuromotor control of affected and adjacent muscle groups in the cervical and lumbar regions, respectively. As recently suggested for the whiplash disease, we suggest the term spinal dyssynergia for this specific pattern of pathology. This suggestion provides a new perspective for the understanding of these diseases by placing their cause within the central nervous system and not in the spine or spinal musculature. This perspective warrants further clinical, neurophysiological, and neuropharmacological studies of this ‘family’ of common yet poorly understood clinical muscular pain conditions along the spine.

Features and impact of dysphagia, dysphonia and laryngeal hypersensitivity in whiplash associated disorder - a qualitative study

PURPOSE

Investigation into dysphagia, dysphonia and laryngeal hypersensitivity after whiplash is limited, offering minimal insight into specific features and impact. This study aimed to explore these symptoms.

MATERIALS AND METHODS

A qualitative interpretive description design was used. Eleven participants with chronic Whiplash Associated Disorder and self-reported swallowing, voice and/or throat-related problems completed baseline symptom questionnaires and were offered a videofluroscopic swallow study to investigate baseline swallowing biomechanics. Semi-structured interviews were conducted to explore features of swallowing, voice and laryngeal sensory complaints and analysed using thematic analysis.

RESULTS

There were high baseline levels of self-reported neck, pain- and throat-related disability and psychological distress. There was no evidence of baseline deficits in swallow biomechanics. Thematic analysis revealed 5 themes: (1) A range of features of dysphagia and dysphonia exist after whiplash with varied clinical course; (2) Activity and participation in swallow and voice activities have changed; (3) There are psychological and emotional impacts; (4) Features of laryngeal hypersensitivity co-exist and (5) There are barriers to management.

CONCLUSIONS

Swallow, voice and laryngeal sensory problems after whiplash were described, with impacts on quality of life and barriers to management. These insights broaden understanding of post-whiplash sequalae, indicating the need for better detection.Implications for rehabilitationDysphagia, dysphonia and laryngeal hypersensitivity are under-recognised consequences of whiplash.Individuals presenting with dysphagia, dysphonia and laryngeal sensory symptoms after whiplash experience significant implications to wellbeing, activity and participation.Improved understanding of these symptoms may facilitate better detection and subsequent referral to speech-language pathology.Greater understanding into the functional and psychosocial implications of these symptoms may guide more effective post-whiplash assessments and informed rehabilitation.

Cervical musculoskeletal, physical and psychological factors associated with ongoing dizziness in patients with whiplash associated disorder, 12 months after undertaking a neck specific or general exercise intervention

BACKGROUND

Exercise in the management of persistent whiplash often doesn't specifically address dizziness. This study aimed to determine cervical musculoskeletal and sensorimotor measures, quality of life and psychological factors associated with the presence of dizziness in individuals with persistent whiplash 12 months post exercise intervention commencement.

METHODS

A retrospective cross sectional review of questionnaires on dizziness, physical and psychological disability, quality of life and physical measures prospectively collected from 172 individuals during a randomised controlled trial. Associations between dizziness at 12 months post intervention and possible predictors was analysed with simple and multiple logistic regression models.

RESULTS

Sixty-three % reported dizziness with a mean University of California Los Angeles dizziness score of 9 (SD 5) and dizziness intensity during activity of 26 mm (SD 24). They had poorer performance on sharpened Rhomberg, Neck muscle endurance (NME), and range of motion, elevated scores on pain, Neck disability index (NDI) and psychological and quality of life measures compared to those without dizziness. Less improvement in NDI and NME flexion from baseline to 12 months post exercise commencement, along with some baseline covariates were related to persistent dizziness and explained 50% of the variance.

CONCLUSION

Dizziness following exercise at 12 months post follow-up was associated with lack of improvement in NDI and NME flexion suggesting a cervicogenic role. Alternatively, the presence of dizziness may inhibit exercise response. Additional causes or contributing factors of dizziness should be investigated in those with persistent whiplash to improve quality of life.

Neck Pain: Do We Know Enough About the Sensorimotor Control System?

Neck pain is a worldwide health problem. Clarifying the etiology and providing effective interventions are challenging for the multifactorial nature of neck pain. As an essential component of cervical spine function, the sensorimotor control system has been extensively studied in both healthy and pathological conditions. Proprioceptive signals generated from cervical structures are crucial to normal cervical functions, and abnormal proprioception caused by neck pain leads to alterations in neural plasticity, cervical muscle recruitment and cervical kinematics. The long-term sensorimotor disturbance and maladaptive neural plasticity are supposed to contribute to the recurrence and chronicity of neck pain. Therefore, multiple clinical evaluations and treatments aiming at restoring the sensorimotor control system and neural plasticity have been proposed. This paper provides a short review on neck pain from perspectives of proprioception, sensorimotor control system, neural plasticity and potential interventions. Future research may need to clarify the molecular mechanism underlying proprioception and pain. The existing assessment methods of cervical proprioceptive impairment and corresponding treatments may need to be systematically reevaluated and standardized. Additionally, new precise motor parameters reflecting sensorimotor deficit and more effective interventions targeting the sensorimotor control system or neural plasticity are encouraged to be proposed.

Respiratory dysfunction in patients with chronic neck pain: systematic review and meta-analysis

PURPOSE

To determine the differences in respiratory muscle strength and pulmonary function between patients with chronic neck pain (CNP) and asymptomatic individuals.

METHODS

Databases were MEDLINE, CINAHL, Scopus, Web of Science and EMBASE up to the end of September 2021. Studies with cross-sectional and longitudinal design were selected, with adult patients with CNP and asymptomatic individuals with reports respiratory function.

RESULTS

11 studies met the inclusion criteria and 10 were included in the meta-analysis showing a statistically significant reduction in inspiratory/expiratory muscle strength (MIP/MEP) in the patients with CNP compared with the asymptomatic individuals (mean difference (MD) for MIP, -11.67 [-14.57 to -8.77]; MD for MEP, -11.80 [-14.99 to -8.60]) and pulmonary function: vital capacity (standardized mean difference (SMD), -0.31 [-0.56 to -0.06]); maximum voluntary ventilation (SMD, -0.36 [-0.59 to -0.14]); forced vital capacity (SMD, -0.53 [-0.99 to -0.06]); peak expiratory flow (SMD, -0.58 [-1.03 to -0.12]); and forced expiratory volume in the first second (SMD, -0.28 [-0.51 to -0.05]).

CONCLUSIONS

Patients with CNP have reduced respiratory muscle strength and pulmonary function compared with asymptomatic individuals, and this difference could be clinically meaningful. However, more studies of high methodological quality and longitudinal studies are needed to strengthen the results of this meta-analysis. IMPLICATIONS FOR REHABILITATIONRespiratory dysfunction has been observed in patients with chronic neck pain.Patients with chronic neck pain present a decrease in respiratory muscle strength and pulmonary function compared with asymptomatic individuals.Respiratory pattern disorders should be considered in the clinical context of chronic neck pain.Interventions focused on respiratory muscle training could be helpful for this population.

Electromyographic Activity of Sternocleidomastoid Muscle in Individuals With Neck Pain and Healthy Volunteers: A Reliability and Between-Group Differences Examination

OBJECTIVES

The purpose of this study was to evaluate the electromyographic activity of the sternocleidomastoid muscle during the performance of the craniocervical flexion test (CCFT) in individuals with neck pain and healthy volunteers, assess the reliability of this method, and examine possible between-population differences.

METHODS

Electromyographic activity of the sternocleidomastoid muscles of 22 individuals with neck pain and 22 healthy participants was recorded during the 55 stages of the CCFT. Pain (visual analog scale) and disability (Neck Disability Index) levels and pain duration were recorded for the participants with neck pain. Reliability of electromyography was evaluated with the intraclass correlation coefficient, standard error of measurement, and minimum detectable change.

RESULTS

Within-day reliability indices of electromyographic activity were very good to excellent (intraclass correlation coefficients, 0.86-0.98; standard error of measurement, 1.8%-7.6%; minimum detectable change, 5.0%-21.1%). For the head-lift normalization method, 2-way analysis of variance revealed significant between-group differences (P < .02); however, these were not clinically significant when reliability test-retest error was considered. Differences between contraction levels were significant (P < .001); however, the group by contraction level interaction factor was nonsignificant. Therefore, the between-groups electromyographic increases noted with increasing contraction levels were similar. No correlation was identified between participants' electromyography data and pain or disability.

CONCLUSION

In participants with moderate pain, disability, and pain duration, no clear alterations in electromyographic activity of the sternocleidomastoid could be detected with the CCFT. Reliability of the test used was very good.

Neck Strength in Coronal and Sagittal Head Movement in Military Pilots and Aircrew With Chronic Neck Pain: A Systematic Review With Meta-Analysis

OBJECTIVE

This systematic review aimed to assess whether there is a difference in neck strength between military pilots and aircrew with and without chronic neck pain.

METHODS

The PubMed, Embase, and Scopus databases were searched. Two independent reviewers selected relevant full articles comparing neck strength between military pilots and aircrew with and without chronic neck pain. Two independent reviewers extracted the data from the full articles selected. A meta-analysis was used to assess standardized mean differences in neck strength based on a random-effects model.

RESULTS

The search returned 3554 results; 5 articles were included in the study. Military pilots and aircrew with chronic neck pain showed no difference in neck strength from military pilots and aircrew without chronic neck pain for flexion and extension, but did show a neck strength reduction for right and left lateral flexion -0.29 (95% confidence interval, -0.52 to -0.06; I² = 3%) and -0.23 (95% confidence interval, -0.45 to 0.00; I² = 0%), respectively.

CONCLUSION

Based on this meta-analysis with a 3a level of evidence, military pilots and aircrew with chronic neck pain have reduced neck strength for coronal head movement, but not sagittal movement compared with military pilots and aircrew without chronic neck pain.

Electromyographic Responses of Neck, Back, and Limb Outlet Muscles Associated With High-Velocity, Low-Amplitude Manual Cervical and Upper Thoracic Spinal Manipulation of Individuals With Mild Neck Disability: A Descriptive Observational Investigation

OBJECTIVES

The purpose of this study was to investigate the extent of electromyographic responses associated with manual high-velocity, low-amplitude (HVLA) spinal manipulation systematically applied to the upper and lower cervical and upper thoracic spines in a cohort with mild neck disability.

METHODS

The study was a descriptive observational investigation, with all participants receiving the same interventions. Nineteen participants with mild neck disability received 6 manual HVLA manipulations to the cervical and upper thoracic spine. Bipolar surface electromyography electrode pairs were used to measure responses of 16 neck, back, and limb outlet muscles bilaterally. The number of electromyographic responses was then calculated.

RESULTS

Electromyographic responses associated with cervical and thoracic manipulation occurred in a median of 4 of the 16 (range: 1-14) recorded muscles. Cervical spinal manipulation was associated with the highest rates of electromyographic responses in neck muscles, whereas responses in back muscles were highest after upper thoracic manipulation.

CONCLUSION

Cervical spinal manipulation was associated with the highest rate of electromyographic responses in muscles of the cervical spine (sternocleidomastoid and splenius cervicis), whereas responses in back muscles (upper and middle trapezius, latissimus dorsi, and longissimus thoracis) were highest after upper thoracic manipulations. This result suggests that electromyographic muscular responses associated with spinal manipulation primarily occur locally (close to the target segment) rather than distally.

The Mode of Activity of Cervical Extensors and Flexors in Healthy Adults: A Cross-Sectional Study

Background and Objectives: The purpose of this study was to investigate the activity of bilateral cervical extensors and flexors on the sagittal, frontal, and horizontal planes of healthy adults during motions of the neck in a sitting position, which has not been satisfactorily investigated by surface electromyogram (sEMG). Materialand Methods: We recruited 35 healthy participants (mean ± standard deviation of age, 20.3 ± 2.4). sEMG recordings of the cervical extensors and flexors were performed for a total of nine seconds in three phases: Phase I involved the motion of the neck from the neutral position to the maximum range of motion; Phase II involved maintaining the neck at the maximum range of motion; and Phase III involved the motion of the neck from the maximum range of motion to the neutral position during neck flexion, extension, right and left lateral flexion, right and left rotation, and maintaining the neck in the neutral position. Muscle activities in each motion were normalized as a percentage of maximal voluntary contraction (%MVC) so that the muscles could be compared. Results: The %MVC of the extensors was significantly larger than that of the flexors in the neutral position (p < 0.001). In addition, the %MVCs of the following were significantly larger than the %MVC in the neutral position: the extensors in flexion (p = 0.014) and extension (p = 0.020), the ipsilateral extensors (p = 0.006) and flexors (p < 0.001) in lateral flexion in Phase I; the flexors in flexion (p < 0.001), the extensors in extension (p = 0.010), and the ipsilateral extensors and flexors in lateral flexion (p < 0.001) in Phase II; the extensors and flexors in flexion (p < 0.001), the flexors in extension (p < 0.001), the ipsilateral flexors (p < 0.001), the contralateral flexors (p = 0.004) and the contralateral extensors (p = 0.018) in lateral flexion in Phase III; and the bilateral extensors and contralateral flexors during rotation in all three phases (p < 0.001). Conclusion: The typical sEMG activities of the extensors and flexors during motion of the neck in healthy adults were identified in this study; this information can be used to understand the pathophysiology of non-specific neck pain and to provide an index for evaluating the effect of treatment.

Assessment of Neuromuscular and Psychological Function in People with Recurrent Neck Pain during a Period of Remission: Cross-Sectional and Longitudinal Analyses

The aim of this study was to examine for the presence of differences in neuromuscular and psychological function in individuals with recurrent neck pain (RNP) or chronic neck pain (CNP) following a whiplash trauma compared to healthy controls. A secondary aim was to examine whether neuromuscular characteristics together with psychological features in people with RNP were predictive of future painful episodes. Multiple features were assessed including neck disability, kinesiophobia, quality of life, cervical kinematics, proprioception, activity of superficial neck flexor muscles, maximum neck flexion and extension strength, and perceived exertion during submaximal contractions. Overall, those with RNP (n = 22) and CNP (n = 8) presented with higher neck disability, greater kinesiophobia, lower quality of life, slower and irregular neck movements, and less neck strength compared to controls (n = 15). Prediction analysis in the RNP group revealed that a higher number of previous pain episodes within the last 12 months along with lower neck flexion strength were predictors of higher neck disability at a 6-month follow-up. This preliminary study shows that participants with RNP presented with some degree of altered neuromuscular features and poorer psychological function with respect to healthy controls and these features were similar to those with CNP. Neck flexor weakness was predictive of future neck disability.

The Whiplash Disease Reconsidered

The natural course of the whiplash disease is reconsidered in relation to the predominant view of its cause. It is assumed that a whiplash-type trauma is causing an acute tissue injury such as a distortion or sprain in the neck followed by neck pain and headache, which then tends to become a chronic pain condition. We conclude that the whiplash disease typically evolves following a minor trauma without any signs of a tissue injury. It presents with central neuromotor dysfunction, such as electromyography (EMG) hyperactivity and abnormal activation patterns associated with dyscoordination of the involved and adjacent muscle groups. This indicates a central neurological rather than a peripheral traumatic pathology. This view places the cause of the whiplash disease within the central nervous system, and, in concordance with the EMG abnormalities and motor dyscoordination, we suggest the term cervical spinal dyssynergia for this pathology. It provides a new paradigm for further investigations of this disease as well as a window for possible specific neuropharmacological therapy directed towards dysfunctional neuromotor control.

Comparison of the effectiveness of a structured exercise program on nonspecific neck pain in string and woodwind players

To investigate the effect of a structured exercise training program on pain, functional status, physical function and quality of life (QoL) in string and woodwind players with nonspecific cervical pain. This study had a prospective cohort design and conducted on 40 musicians (26 male, 14 female) aged between 18 and 65 years with persistent nonspecific neck pain in the previous 3 months. Forty musicians were assigned to either violin (n = 20, median age; 26.5 year, height; 1.67 m, body mass; 65 kg, BMI; 23.04 kg/m²) or ney group (n = 20, median age; 27.5 year, height; 1.81 m, body mass; 75 kg, BMI; 23.35 kg/m²) and followed the same structured exercise program (3 days/per week for 8 weeks). The primary outcome was neck pain intensity and assessed on a visual analog scale (VAS). Secondary outcomes; cervical range of motion (ROM) was measured using a goniometer, the jaw-to-sternum and jaw-to-wall distances were used for the assessment of cervical mobility, neck, shoulder and back muscles strength were assessed with a hand-held dynamometer, the Northwick Park Neck Pain and Short Form 36 (SF-36) questionnaires were also used. Normality of data distribution was checked using the Kolmogorov-Smirnov test. For evaluating the training effectiveness on outcome measures, Mann-Whitney U and Wilcoxon test were used compare pre-test and post-test values with/within groups, respectively. The primary outcome (pain intensity) was lowered %33 in both groups. However, the mean change was found similar (median mean changes; -2 for both groups) (p > 0.05). The secondary outcomes; cervical mobility, cervical flexion ROM, disability and muscle strength of the left middle trapezius, left hand grip, anterior and middle parts of the right deltoid, and cervical flexors also significantly improved in both groups (p < 0.05). Only the mean changes of right serratus anterior, middle trapezius and cervical flexor muscles were higher in violin group than ney group (p < 0.05). There was no significant difference in the cervical extension, right rotation, left rotation, right lateral flexion and left lateral flexion after the treatment in both groups (p > 0.05). There was no significant difference between the groups after the exercise program in terms of pain, mobility, range of motion and SF-36 subdomains (p > 0.05). Specific exercise program had similar positive effects on pain, cervical mobility, cervical fexion ROM and disability in string and woodwind players. Although several muscles showed similar improvements in strength, some muscle groups recovered differently. Physical needs specific to the instrument and performance should be taken into account when prescribing exercises to musicians having the same problem, but playing different instruments.

Dores musculares cervicais em pacientes com DTM e suas correlações

Resumo Introdução As disfunções temporomandibulares apresentam uma variedade de sinais e sintomas que afetam a articulação temporomandibular, músculos da mastigação e estruturas relacionadas e muitos pacientes apresentam queixas cervicais. Objetivo Verificar a correlação de dor à palpação dos músculos da mastigação (masseter, temporal anterior, pterigoideos lateral e medial) e digástrico, com a queixa de dor no pescoço; verificar a correlação de dor à palpação nos músculos da mastigação e digástrico, com dor à palpação no esternocleidomastoideo e trapézio, e se a força de correlação é diferente entre eles. Material e método Foram avaliados 232 prontuários da clínica odontológica das Disfunções Temporomandibulares da Faculdade de Odontologia de Araçatuba, do período de 2011 a 2013. Os dados coletados foram submetidos à análise estatística, com alfa (α) = 0.01 para todos os casos, exceto digástrico quando associado ao trapézio (α) = 0.05. Resultado A maioria dos pacientes era do sexo feminino. Houve correlação positiva entre dor à palpação nos músculos temporal, masseter, pterigoideo lateral, esternocleidomastoideo e trapézio, e queixa de dor no pescoço. Também houve correlação positiva entre a dor em todos os músculos da mastigação (masseter, temporal, pterigoideo lateral e medial) e digástrico e a dor no esternocleidomastoideo. Bem como a correlação de presença de dor nos músculos masseter, temporal, pterigoideo lateral e digástrico com dor no trapézio. A correlação de dor foi mais forte para o músculo esternocleidomastoideo, exceto para o pterigoideo lateral. Conclusão Existe correlação positiva entre a queixa de dor à palpação nos músculos da mastigação, exceto pterigiodeo medial, e os músculos cervicais (esternocleidomastoideo e trapézio). A força de correlação entre a dor do masseter e temporal anterior com o esternocleidomastoideo é mais forte do que com o trapézio.

Altered neuromuscular activity and postural stability during standing balance tasks in persons with non-specific neck pain

OBJECTIVES

To compare neck, trunk, and lower extremity muscle activity in standing in persons with neck pain (NP) to healthy controls and determine associations with postural sway.

METHODS

Participants included 25 persons with NP and 25 controls. Surface electromyography was recorded bilaterally from neck (sternocleidomastoid, SCM; splenius capitis, SC; upper trapezius, UT), trunk (erector spinae, ES), and lower extremity (rectus femoris, RF; biceps femoris, BF; tibialis anterior, TA; medial gastrocnemius, GN) muscles. Postural sway was measured using a force platform in narrow stance with eyes open/closed, on firm/soft surfaces.

RESULTS

Compared to controls, the NP group demonstrated higher activity in all muscles, except UT and had higher amplitude ratios for neck muscles (SCM, SC) for all tasks (p < .05). No between-group difference was found in amplitude ratios for lower extremity muscles, except for GN. Lower extremity activity was moderately correlated with larger postural sway for both groups (r = 0.41-0.66, p < .05). There were no correlations between sway and neck and trunk muscle activity (p > .05).

CONCLUSION

Increased muscle activity with NP is associated with increased postural sway. Both groups used similar postural control strategies, but the increased neck activity in the NP group is likely related to the NP disorder rather than postural instability.

Effects of Global Postural Reeducation versus Specific Therapeutic Neck Exercises on Pain, Disability, Postural Control, and Neuromuscular Efficiency in Women with Chronic Nonspecific Neck Pain: Study Protocol for a Randomized, Parallel, Clinical Trial

Background: Chronic nonspecific neck pain is the most frequent form of neck pain. It is more prevalent in women, and a costly public health issue. It is commonly associated with biomechanical, functional, proprioceptive, and postural impairments. The aim of this trial is to compare the effects of global postural exercises versus specific therapeutic exercises on neck pain, disability, mobility, pressure pain threshold, kinesiophobia, pain catastrophizing, postural control, and neuromuscular efficiency in women with chronic nonspecific neck pain. Methods and analysis: This study is a randomized, parallel-group and single blinded clinical trial. Sixty-two women with nonspecific chronic neck pain were recruited from the community of Guarda, Portugal, and randomly assigned to one of two intervention groups: (1) global postural reeducation (GPR group), (2) specific therapeutic exercises (STE group). The intervention was carried out over 4 weeks, with two sessions per week (eight sessions), and applied by a physiotherapist and paired with a daily individual at-home-exercise program. Primary outcomes are neck pain intensity and disability (Numerical Pain Rating Scale, Neck Disability Index). Secondary outcomes are cervical mobility and pressure pain threshold (CROM, algometry), attitude to pain (kinesiophobia, pain catastrophizing), standing postural control (Center of Pressure (COP) displacements), and neuromuscular efficiency (electromyography). There are four points of evaluation where the outcomes were assessed twice before the intervention, 1 week apart, and the two post-intervention assessments will be carried out after four and eight sessions. The objective was to increase scientific knowledge of different exercise modalities, such as global postural reeducation, in musculoskeletal disorders. Trial registration: ClínicalTrials.gov (NCT04402463), prospectively registered (data 22 May 2020).

The effects of combined sternocleidomastoid muscle stretching and massage on pain, disability, endurance, kinesiophobia, and range of motion in individuals with chronic neck pain: A randomized, single-blind study

BACKGROUND

The effect of interventions to the Sternocleidomastoid (SCM)-muscle, as an important element of neck movement which is overactive in individuals with chronic neck pain (CNP), are unknown.

OBJECTIVE

The aim of the current study is to investigate the effects of SCM stretching and massage on pain, range of motion (ROM), endurance, disability, and kinesiophobia in individuals with CNP.

METHODS

In this study, individuals with CNP were randomized 1:1 to parallel SCM-Group (n = 30) or control group (CG) (n = 30). Conventional physiotherapy was applied to CG. In addition to the same interventions applied to the CG, classical massage and stretching exercises were applied to the SCM-muscle in the SCM-Group. Treatment sessions were administered three times each week for a total of 5 weeks. Pain, endurance, ROM, disability, and kinesiophobia were evaluated. Both prior to and immediately following the treatments. Mixed-model repeated measured ANOVAs were then employed to determine if a group*time interaction existed on the effects of the treatment on each outcome variable for each group as the between-subjects variable and time as the within-subjects variables.

RESULTS

Improvements in pain, disability, ROM(extension, left-lateral flexion, and right/left-rotation), and endurance were found to be greater in the SCM-Group compared to the CG (p < 0.05). Changes in flexion and right-lateral flexion ROM and kinesiophobia did not significantly differ between the groups (p > 0.05).

CONCLUSION

Stretching exercises and massage applied to the SCM-muscle, together with conventional physiotherapy, can reduce pain and disability, and increase ROM and endurance in individuals with CNP. This treatment may therefore be considered for use as an alternative method in treating CNP. The study was registered in ClinicalTrials.gov (NCT04345042).

Impaired neck motor control in chronic whiplash and tension-type headache

OBJECTIVES

The purpose of this study is twofold, first to present a new method based on head laser tracking designed to measure head or hand movements and second to further investigate if patients suffering from chronic whiplash or tension-type headache have impaired motor control of neck muscles.

MATERIAL AND METHODS

A new laser tracking instrument was designed to measure the ability of a test person to track a reference point moving on the wall by a laser fixed to the forehead or held in the hand. The reference point to be tracked moves in runs of a circle or a square at three different speeds 10, 20, or 30 cm/s. We used a 1 × 1 ×1 m setup geometry to provide head movements well below pain release. Groups of 22 patients diagnosed with chronic whiplash-associated disorder grade 2, 19 patients diagnosed with chronic tension-type headache, and 37 control persons were compared.

RESULTS

A small but highly significant dyscoordination of head movements was observed in both patient groups and in whiplash also of the hand.

CONCLUSIONS

Our study presents a new method based on laser tracking for precision quantitative measurements of head or hand movements during standardized conditions. The results confirm that motor control of head movements is impaired in both chronic whiplash and tension-type headache, and in whiplash also of the hand. This suggests involvement of the central nervous system in the pathology of these diseases.

An investigation of neck pain in older adults, and its relation with shoulder position sense and upper extremity function

PURPOSE

Neck pain is a musculoskeletal problem increasing with age. The disorders that occurs in the neck region may also affect the upper extremity due to its close anatomical relationships. The aim of this study was to determine whether neck pain affects shoulder position sense and upper extremity function in the older adults.

METHODS

This cross-sectional study was carried out in nursing homes. The older adults over 65 years of age with chronic neck pain for the last 6 months were included. Pain intensity was evaluated with a Visual Analog Scale. Acumar dual digital inclinometer was used for the evaluation of shoulder position sense. 9-Hole Peg Test was used for the measure of upper extremity function.

RESULTS

It was found dominant side shoulder position sense and the function of both upper extremities were different between the three groups (p < 0.05). Pain was correlated with dominant and non-dominant 60ᵒ flexion shoulder position sense and 60ᵒ abduction shoulder position sense (p < 0.05). Additionally, a relationship was found only between pain and non-dominant side upper extremity function (p < 0.05).

CONCLUSION

In conclusion, we found that in older adults with neck pain, position sense and function decreased in upper extremities. The findings from this study support that detailed evaluation of anatomically related regions as well as the cervical region where pain is felt is important in creating a more effective rehabilitation program.

Dynamic alterations of amplitude of low-frequency fluctuations in patients with chronic neck pain

Background

The pathogenesis of neck pain in the brain, which is the fourth most common cause of disability, remains unclear. Furthermore, little is known about the characteristics of dynamic local functional brain activity in cervical pain.

Objective

The present study aimed to investigate the changes of local brain activity caused by chronic neck pain and the factors leading to neck pain.

Methods

Using the amplitude of low-frequency fluctuations (ALFF) method combined with sliding window approach, we compared local brain activity that was measured by the functional magnetic resonance imaging (fMRI) of 107 patients with chronic neck pain (CNP) with that of 57 healthy control participants. Five pathogenic factors were selected for correlation analysis.

Results

The group comparison results of dynamic amplitude of low-frequency fluctuation (dALFF) variability showed that patients with CNP exhibited decreased dALFF variability in the left inferior temporal gyrus, the middle temporal gyrus, the angular gyrus, the inferior parietal marginal angular gyrus, and the middle occipital gyrus. The abnormal dALFF variability of the left inferior temporal gyrus was negatively correlated with the average daily working hours of patients with neck pain.

Conclusions

The findings indicated that the brain regions of patients with CNP responsible for audition, vision, memory, and emotion were subjected to temporal variability of abnormal regional brain activity. Moreover, the dALFF variability in the left inferior temporal gyrus might be a risk factor for neck pain.This study revealed the brain dysfunction of patients with CNP from the perspective of dynamic local brain activity, and highlighted the important role of dALFF variability in understanding the neural mechanism of CNP.

Efficacy of Manual Therapy and Transcutaneous Electrical Nerve Stimulation in Cervical Mobility and Endurance in Subacute and Chronic Neck Pain: A Randomized Clinical Trial

Neck pain is a frequent health problem. Manual therapy (MT) and transcutaneous electrical nerve stimulation (TENS) are recommended techniques for treatment of mechanical neck disorders (MND) in Spanish Public Primary Care Physiotherapy Services. The aim of this study was to compare the efficacy of MT versus TENS in active mobility and endurance in cervical subacute or chronic neck pain. Ninety patients with MND were randomly allocated to receive ten 30-min sessions of either MT or TENS, in a multi-centered study through 12 Primary Care Physiotherapy Units in the Madrid community. Active cervical range of motion (CD-ROM) and endurance (Palmer and Epler test) were evaluated pre- and post-intervention and at 6-month follow-up. A generalized linear model of repeated measures was constructed for the analysis of differences. Post-intervention MT yielded a significant improvement in active mobility and endurance in patients with subacute or chronic MND, and at 6-month follow-up the differences were only significant in endurance and in sagittal plane active mobility. In the TENS group, no significant improvement was detected. With regard to other variables, MT improved mobility and endurance more effectively than TENS at post-intervention and at 6-month follow-up in the sagittal plane. Only MT generated significant improvements in cervical mobility and endurance in the three movement planes.

Cervical movement kinematic analysis in patients with chronic neck pain: A comparative study with healthy subjects

BACKGROUND

Several studies have investigated cervical kinematic performance in patients with chronic neck pain, especially with fast movements. A recent systematic review recommended further study of cervical spine kinematics cervical motions in individuals with neck pain.

OBJECTIVES

This study aimed to examine cervical spine kinematics of naturally paced cervical motions in patients with chronic neck pain compared with a group of asymptomatic participants. Also, the relationships between cervical kinematic measures with neck pain intensity and disability were determined.

METHOD

Kinematic performance was measured in 20 individuals with chronic nonspecific neck pain and 20 healthy controls. Data were captured using a 7-camera motion analysis system. Parameters were range of cervical motion, peak velocity, duration of movement, and jerk index (smoothness of movement). Pain intensity and Neck Disability Index were also measured.

RESULTS

Duration of movements, peak velocities, and jerk indexes were significantly different between the two groups (p < 0.05). Pain intensity was significantly associated with duration of movement, range of motion, peak velocity, and smoothness predominantly in extension (r range = 0.4 to 0.6, p < 0.05).

CONCLUSION

This study's findings indicated altered cervical kinematic performance during naturally paced motions (particularly reduced smoothness of movement)in patients with chronic nonspecific neck pain compared to asymptomatic participants. Also, pain intensity was moderately associated with most kinematic measures, especially in extension. This study's results can help to understand better the impairments associated with chronic nonspecific neck pain.

Novel assessment of the variation in cervical inter-vertebral motor control in a healthy pain-free population

Spinal control at intervertebral levels is dependent on interactions between the active, passive and neural control elements. However, this has never been quantifiable, and has therefore been outside the reach of clinical assessments and research. This study used fluoroscopy during repeated unconstrained flexion and return neck movements to calculate intersegmental motor control (MC), defined as the difference and variation in repeated continuous angular motion from its average path. The study aimed to determine control values for MC at individual levels and its variability. Twenty male volunteers aged 19–29 received fluoroscopic screening of their cervical spines during 4 repetitions of neutral to full flexion and return motion. Moving vertebral images from C0–C1 to C6–C7 were tracked using cross-correlation codes written in Matlab. MC for each level was defined as the mean of the absolute differences between each repetition’s angular path and their mean and its variability as represented by the SD. 1-way ANOVA and Tukey multiple comparisons were used to identify significant contrasts between levels. The mean MC differences and SDs were highest at C1-2, suggesting that this level has the least control and the most variability. Results at this level alone were highly significant (F-ratio 10.88 and 9.79 P < 0.0001). Significant contrasts were only found between C1-C2 and all other levels. The mean MC difference for summed C1-6 levels was 3.4° (0.7–6.1). This study is the first to quantify intervertebral MC in the cervical spine in asymptomatic people. Studies of neck pain patients are now merited.