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Background: Shoulder pain is the third most common musculoskeletal disorder yet diagnosis remains challenging. In some cases, shoulder symptoms can be partially attributed to a cervical origin., Objectives: To estimate the prevalence of cervical contribution in patients presenting with shoulder pain. To determine symptom reproduction and symptom modification (i.e., pain intensity and pain location) after cervical spine screening (CSS) and compare these changes between patients with and without cervical contribution., Design: Observational study., Method: Sixty patients were included. Cervical contribution was present if a ≥30.0% change in shoulder pain intensity on active movement was recorded after CSS. The CSS consisted of several tests and shoulder symptom modification or reproduction was noted. The presence of a centralization phenomenon was also noted and was considered to be present if the location of pain diminished from more distal areas after the CSS., Results: A 50.0% prevalence of cervical contribution (CI95% 37,35-62,65) was found. Cervical contribution was more likely in those that demonstrated centralization of their pain after the CSS (p = 0.002) and those that had a history of previous neck pain (p = 0.007). Symptom reproduction occurred for 23 out of the 60 participants (38.3%), being present in 18 of those with cervical contribution (60.0%). After the CSS, a statistically significant decrease of shoulder pain intensity was found for those classified as having cervical contribution (p < 0.001)., Conclusions: Cervical contribution is prevalent in 50% of patients presenting with shoulder pain; this was evidenced as shoulder symptom modification and, to a lesser extent, symptom reproduction following a CSS., Competing Interests: Declaration of competing interest None., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: The physical and cognitive demands of combat flying may influence the development and persistence of flight-related neck pain (FRNP). The aim of this pilot study was to analyse the effect of a multimodal physiotherapy program which combined supervised exercise with laser-guided feedback and interferential current therapy on psychophysiological variables in fighter pilots with FRNP., Methods: Thirty-one fighter pilots were randomly assigned to two groups (Intervention Group: n = 14; Control Group: n = 17). The intervention consisted of 8 treatment sessions (twice per week) delivered over 4 weeks. The following primary outcomes were assessed: perceived pain intensity (Numeric Pain Rating Scale-NPRS) and Heart Rate Variability (HRV; time-domain, frequency-domain and non-linear variables). A number of secondary outcomes were also assessed: myoelectric activity of the upper trapezius and sternocleidomastoid, pain catastrophizing (Pain Catastrophizing Scale-PCS) and kinesiophobia (TSK-11)., Results: Statistically significant differences (p≤0.05) within and between groups were observed for all outcomes except for frequency domain and non-linear HRV variables. A significant time*group effect (one-way ANOVA) in favour of the intervention group was found for all variables (p<0.001). Effect sizes were large (d≥0.6)., Conclusions: The use of a multimodal physiotherapy program consisting of supervised exercise with laser-guided feedback and interferential current appears to show clinical benefit in fighter pilots with FRNP., Trial Registration: ClinicalTrials.gov: NCT05541848., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Fernández-Morales et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Objective: To understand whether pain-related factors soon after a whiplash injury can explain the presence of chronic headache., Materials and Methods: A prospective study with a follow-up of 6 months was performed, including 42 patients with acute whiplash-associated disorders. Neck pain intensity, the Neck Disability Index, the Tampa Scale of Kinesiophobia, the Pain Catastrophizing Scale, and the Anxiety State-Trait Scale were assessed at baseline. Differences in clinical characteristics between those with and without headache at 6 months were determined. The relative risk of presenting with headache was evaluated. A logistic regression model was performed to assess which factors at baseline could explain the presence of headache at 6 months., Results: At 6 months, one-third of the sample presented with chronic headache. Significant differences were found for several outcome measures when people with and without headache were compared ( P <0.001). The highest relative risk of presenting with headache was found for moderate/severe levels of pain catastrophizing during the acute phase (RR=15.00, 95% CI=3.93, 57.22). The level of neck pain intensity and pain catastrophizing at baseline partially explained the presence of headache at 6 months ( R2 =0.627)., Discussion: The risk of presenting with persistent headache attributed to a whiplash injury is increased when people present with higher neck pain intensity and pain catastrophizing soon after a whiplash injury. Evaluating neck pain intensity and pain catastrophizing at baseline may assist in identifying those more likely to develop chronic headache, potentially providing an opportunity for early targeted interventions., Competing Interests: The authors declare no conflict of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Introduction: People with chronic neck pain (CNP) commonly exhibit a range of physical impairments including cervical proprioceptive deficits. Assessing proprioception using a head mounted laser to assess joint position error (JPE) is a reliable and valid measure. However, the responsiveness of this measure has not been assessed., Objective: To assess the responsiveness of the measure of cervical JPE after a 4-week home-based neck proprioceptive training intervention in people with CNP., Design: An observational study to assess the responsiveness of the measure of cervical JPE., Methods: The JPE test was assessed in people with CNP before and after 4 weeks of neck proprioception training. JPE was assessed as participants performed neck joint position sense tests for flexion, extension, right rotation, and left rotation in sitting and standing which were performed in a random order. Both the absolute and constant JPE were assessed. The intervention consisted of neck repositioning exercises as well as movement sense exercises. Cohen's d effect size was used to assess the internal responsiveness of the JPE test. The Pearson's correlation was used to assess the change of scores of the laser pointer and measures from inertial measurement units (IMUs) (external responsiveness)., Results: After 4 weeks of proprioception training, JPE assessed in sitting reduced from 2.69◦-3.57◦ to 1.88◦-1.98◦ for flexion, extension, and right rotation with large effect sizes (Cohen's d range: 1.25-2.00). For left rotation, JPE reduced from 3.23◦ to 1.9◦, and the effect size was close to being large (Cohen's d: 0.79). When assessed in standing, JPE reduced from 3.49◦-4.52◦ to 1.5◦-2.33◦ with large effect sizes (Cohen's d range: 0.89-1.25) for flexion, extension, right rotation, and left rotation. Large effect sizes were not observed for the constant JPE when assessed in either sitting or standing. The assessment of the external responsiveness revealed weak correlations between the change of scores obtained from the laser pointer and the IMUs for all movements, apart from the constant JPE in sitting for left rotation, which showed a strong correlation (r = 0.7)., Conclusion: The results of this study showed that the measure of the JPE has sufficient internal responsiveness, however, the external responsiveness was inadequate. Further research is advised., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 AlDahas et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Previous systematic reviews have identified the benefits of exercise for chronic neck pain on subjective reports of pain, but not with objective measures such as quantitative sensory testing (QST). A systematic review was conducted to identify the effects of neck specific exercise on QST measures in adults with chronic neck pain to synthesise existing literature and provide clinical recommendations., Methods: The study protocol was registered prospectively with PROSPERO (PROSPERO CRD42021297383). For both randomised and non-randomised trials, the following databases and trial registries were searched: AMED, CINAHL, Embase, Google Scholar, Medline, PEDro, PubMed, Scopus, SPORTDiscus, Science Citation Index and Social Science Citation Index from Web of Science Core Collection, clinicaltrials.gov, GreyOpen, and ISRCTN registry. These searches were conducted from inception to February 2022 and were updated until September 2023. Reference lists of eligible studies were screened. Study selection was performed independently by two reviewers, with data extraction and quality appraisal completed by one reviewer and independently ratified by a second reviewer. Due to high heterogeneity, narrative synthesis was performed with results grouped by exercise type., Findings: Three trials were included. Risk of bias was rated as moderate and the certainty of evidence as low or moderate for all studies. All exercise groups demonstrated statistically significant improvement at an intermediate-term follow-up, with progressive resistance training combined with graded physical training demonstrating the highest certainty of evidence. Fixed resistance training demonstrated statistically significant improvement in QST measures at a short-term assessment., Interpretation: Fixed resistance training is effective for short-term changes in pain sensitivity based on low-quality evidence, whilst moderate-quality evidence supports progressive resistance training combined with graded physical training for intermediate-term changes in pain sensitivity., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Osborne et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Exercise is recommended for office workers with neck pain. However, recent reviews evaluated the effectiveness of workplace interventions only., Objectives: To evaluate the effect of exercise on pain, disability, and quality of life (QoL) in office workers with chronic neck pain., Design: Systematic review with meta-analysis., Methods: Electronic databases were searched from inception to April 30, 2022, to identify studies in which participants were adults aged ≥18 years undergoing any form of neck exercises (e.g., strengthening, motor control) or physical activity (e.g., aerobic exercise) performed for a minimum of two-weeks without any other additional treatment besides advice or education. Two reviewers independently screened papers and determined the certainty of the evidence., Results: Eight randomised controlled trials met the eligibility criteria. Seven studies reported a significant decrease in Visual Analogue Scale (VAS) scores for neck pain intensity and five studies reported a significant decrease in Neck Disability Index (NDI) scores following strengthening exercises. Only one study assessed the effect of strengthening exercises on QoL and reported no significant effect. All eight included studies had a high risk of bias and the overall certainty of evidence was low. Meta-analyses demonstrated a significant decrease of neck pain intensity and disability for strengthening exercises compared to a control (p < 0.01)., Conclusion: There is low certainty of evidence that strengthening of the neck, shoulder and scapular musculature is effective at reducing neck pain and disability in office workers. Further research evaluating the effect of exercise on QoL is required., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Introduction: Proprioception can be impaired in people with neck pain. The cervical joint position sense test, which measures joint position error (JPE), is the most common test used to assess neck proprioception. The aim of this systematic review was to assess the measurement properties of this test for the assessment of people with and without neck pain., Methods: This systematic review was registered prospectively on Prospero (CRD42020188715). It was designed using the COSMIN guidelines and reported in line with the PRISMA checklist. Two reviewers independently searched Medline, Embase, SportDiscus, and CINAHL Plus databases from inception to the 24th July 2022 with an update of the search conducted until 14th of October 2023. The COSMIN risk of bias checklist was used to assess the risk of bias in each study. The updated criteria for good measurement properties were used to rate individual studies and then the overall pooled results. The level of evidence was rated by two reviewers independently using a modified GRADE approach., Results: Fifteen studies were included in this review, 13 reporting absolute JPE and 2 reporting constant JPE. The measurement properties assessed were reliability, measurement error, and validity. The measurement of JPE showed sufficient reliability and validity, however, the level of evidence was low/very low for both measurement properties, apart from convergent validity of the constant JPE, which was high., Conclusion: The measure of cervical JPE showed sufficient reliability and validity but with low/very low levels of evidence. Further studies are required to investigate the reliability and validity of this test as well as the responsiveness of the measure., (© 2024. The Author(s).)

Objective: The Patient-Specific Functional Scale (PSFS) is a patient-reported outcome measure used to assess functional limitations. Recently, the PSFS 2.0 was proposed; this instrument includes an inverse numeric rating scale and an additional list of activities that patients can choose. The aim of this study was to assess the test-retest reliability, measurement error, responsiveness, and minimal important change of the PSFS 2.0 when used by patients with nonspecific neck pain., Methods: Patients with nonspecific neck pain completed a numeric rating scale, the PSFS 2.0, and the Neck Disability Index at baseline and again after 12 weeks. The Global Perceived Effect (GPE) was also collected at 12 weeks and used as an anchor. Test-retest measurement was assessed by completion of a second PSFS 2.0 after 1 week. Measurement error was calculated using a Bland-Altman plot. The receiver operating characteristic method with the anchor (GPE) functions as the reference standard was used for calculating the minimal important change., Results: One hundred patients were included, with 5 lost at follow-up. No floor and ceiling effects were reported. In the test-retest analysis, the mean difference was 0.15 (4.70 at first test and 4.50 at second test). The ICC (mixed models) was 0.95, indicating high agreement (95% CI = 0.92-0.97). For measurement error, the upper and lower limits of agreement were 0.95 and -1.25 points, respectively, with a smallest detectable change of 1.10. The minimal important change was determined to be 2.67 points. The PSFS 2.0 showed satisfactory responsiveness, with an area under the curve of 0.82 (95% CI = 0.70-0.93). There were substantial to high correlations between the change scores of the PSFS 2.0 and the Neck Disability Index and GPE (0.60 and 0.52, respectively; P < .001)., Conclusion: The PSFS 2.0 is a reliable and responsive patient-reported outcome measure for use by patients with neck pain., (© The Author(s) 2023. Published by Oxford University Press on behalf of the American Physical Therapy Association.)

Background: People with chronic neck pain (CNP) often present with impaired neck proprioception. The most widely used clinical test for assessing neck proprioception is cervical joint position sense which measures joint position error (JPE). This clinical test is typically performed using a laser pointer to examine the accuracy of returning to a neutral head position (NHP) or target head position (THP) following active neck movements. The aim of this study was to determine the measurement properties of JPE using a laser pointer when tested in people with and without CNP under a variety of different testing conditions (i.e., different movement directions, sitting versus standing, NHP versus THP)., Methods: Forty-three participants (23 asymptomatic and 20 with CNP) underwent neck proprioception testing, returning to a NHP and THP in both sitting and standing positions (six trials for each test). A laser pointer was secured on the participant's forehead and inertial measurement unit (IMU) sensors were placed beneath the laser pointer and at the level of the spinous process of the seventh cervical vertebra. Both the absolute and the constant JPE were assessed., Findings: For the asymptomatic participants, good reliability (ICC: 0.79) was found only for right rotation of the THP task in sitting. In standing, good reliability (ICC: 0.77) was only found in flexion for the THP task. In standing, good reliability (ICC: 0.77) was only found for right rotation of the THP for the absolute JPE and left rotation (ICC: 0.85) for the constant error of the NHP task. In those with CNP, when tested in sitting, good reliability was found for flexion (ICC: 0.8) for the absolute JPE and good reliability (ICC range: 0.8-0.84) was found for flexion, extension, and right rotation for the constant JPE. In standing, good reliability (ICC range: 0.81-0.88) was found for flexion, and rotation for the absolute JPE. The constant JPE showed good reliability (ICC: 0.85) for right rotation and excellent reliability (ICC: 0.93) for flexion. Validity was weak to strong (r range: 0.26-0.83) and moderate to very strong (r range: 0.47-0.93) for absolute and constant error respectively, when tested in sitting. In standing, the validity was weak to very strong (0.38-0.96) for the absolute JPE and moderate to very strong (r range: 0.54-0.92) for the constant JPE., Conclusion: The reliability of the measure of JPE when tested in sitting and standing in both groups showed good reliability, but not for all movements. The results of the current study also showed that the laser pointer correlated well with the Noraxon IMUs, but not for all movements. The results of the current study support the use of the JPE using a laser pointer in clinical and research settings., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 AlDahas et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Office workers are specifically vulnerable to headache conditions. Neck pain is reported by almost 80% of patients with headaches. Associations between currently recommended tests to examine cervical musculoskeletal impairments, pressure pain sensitivity and self-reported variables in headache, are unknown. The aim of this study is to evaluate whether cervical musculoskeletal impairments and pressure pain sensitivity are associated with self-reported headache variables in office workers., Methods: This study reports a cross-sectional analysis using baseline data of a randomized controlled trial. Office workers with headache were included in this analysis. Multivariate associations, controlled for age, sex and neck pain, between cervical musculoskeletal variables (strength, endurance, range of motion, movement control) and pressure pain threshold (PPT) over the neck and self-reported headache variables, such as frequency, intensity, and the Headache-Impact-Test-6, were examined., Results: Eighty-eight office workers with a 4-week headache frequency of 4.8 (±5.1) days, a moderate average headache intensity (4.5 ± 2.1 on the NRS), and "some impact" (mean score: 53.7 ± 7.9) on the headache-impact-test-6, were included. Range of motion and PPT tested over the upper cervical spine were found to be most consistently associated with any headache variable. An adjusted R 2 of 0.26 was found to explain headache intensity and the score on the Headache-Impact-Test-6 by several cervical musculoskeletal and PPT variables., Discussion: Cervical musculoskeletal impairments can explain, irrespective of coexisting neck pain, only little variability of the presence of headache in office workers. Neck pain is likely a symptom of the headache condition, and not a separate entity., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2023. Published by Elsevier Ltd.)

Introduction: Neck-specific exercises (NSEs) are commonly used for the treatment of chronic non-specific neck pain (CNSNP). However, it remains unclear whether baseline features can predict the response to neck-specific exercise (NSE) in people with CNSNP. This systematic review aims to assess whether baseline features such as age, gender, muscle activity, fatigability, endurance and fear of movement can predict pain and disability reduction following a NSE intervention., Methods and Analysis: This systematic review and meta-analysis will be reported in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Protocols guidelines checklist. The Web of Science, PubMed, Scopus, MEDLINE, Embase and CINAHL databases; key journals; and grey literature will be searched up until June 2023, including medical subject heading terms and keywords combinations. Included studies will investigate an association between the baseline features and pain and disability outcomes following NSE in people with CNSNP. Two independent reviewers will oversee the searching, screening, data extraction and assessment of risk of bias. The risk of bias will be assessed using the Risk Of Bias In Non-randomised Studies of Interventions (ROBINS-I) and Risk-Of-Bias tool for randomised trials 2 (ROB 2). The quality of evidence will be assessed using the Grading of Recommendations Assessment, Development and Evaluation approach (GRADE). Using standardised forms, details regarding study characteristics, baseline features (predictive factors), intervention, primary outcome and effect size (OR and 95% CI of each predictive factor and p value) will be extracted from included studies. Meta-analyses will be considered, if the studies are sufficiently homogeneous and if three or more studies investigate the same or comparable factors that predict the same response (pain intensity or disability). In the event that less than three studies investigated the same factors, a narrative synthesis will be conducted., Ethics and Dissemination: Ethical approval will not be required as this review will be based on published studies. The results of this study will be submitted to a peer-reviewed journal and presented at conferences., Prospero Registration Number: CRD42023408332., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Neck pain is associated with decreased health-related quality of life, decreased work productivity, and increased visits to health care providers., Aim: The aim of this study was to assess the effectiveness of "Global Postural Re-education" (GPR) versus a neck specific exercise (SE) program on neck pain, disability, cervical range of movement, postural stability, and activity of the superficial cervical flexor muscles., Design: A parallel-group and single-blinded clinical trial., Setting: Community interventions., Population: Fifty women with non-specific chronic neck pain (NSCNP)., Methods: Participants were randomly assigned to one of the two intervention groups (GPR [N.=25] or SE [N.=25]). Both interventions consisted of eight sessions of ~40 minutes duration, performed twice a week, for four weeks. Outcomes included neck pain intensity and disability, cervical range of motion (CROM), postural sway, and activity of the superficial neck flexor muscles during a cranio-cervical flexion test (CCFT). All outcomes were assessed twice before the intervention and immediately following eight treatment sessions over four weeks., Results: Both interventions were equally effective in reducing neck pain (P<0.001, ŋp 2 =0.770) and disability (P<0.001, ŋp 2 =0.306), improving neck mobility (P<0.001, 0.385≤ŋp 2 ≤0.623, for all measurements) and decreasing the activity of the superficial cervical flexor muscles (P>0.001). Neither intervention altered postural sway., Conclusions: Our results revealed that GPR and SE induced significant positive results in all measures apart from postural stability but with no difference between the interventions., Clinical Rehabilitation Impact: "Global Postural Re-education" (GPR) and neck SE interventions are equally effective in reducing neck pain and disability, and improving neck mobility in women with NSCNP. Overall, this study indicates that GPR and SE interventions can be used to effectively manage patients with NSCNP.

Background: Measurement of neck muscle strength is common during the assessment of people with chronic neck pain (CNP). This systematic review evaluates the measurement properties (reliability, validity, and responsiveness) of neck muscle strength measures in people with CNP., Databases and Data Treatment: This systematic review followed a PROSPERO registered protocol (CRD42021233290). Electronic databases MEDLINE (OVID interface), CINAHL, SPORTDiscuss via (EBSCO interface), EMBASE (OVID interface), and Web of Science were searched from inception to 21 June 2021. Screening, data extraction, and quality assessment (Consensus-based Standards for the selection of Health Measurement Instruments (COSMIN) checklist) were conducted independently by two reviewers. The overall strength of evidence was evaluated using the modified Grading of Recommendations Assessment, Development and Evaluation., Results: From 794 records, nine articles were included in this review which concerned six different neck strength outcome measures. All studies evaluated reliability and one evaluated construct validity. The reliability of neck strength measures ranged from good to excellent. However, the risk of bias was rated as doubtful/inadequate for all except one study and the overall certainty of evidence was rated low/very low for all measures except for the measurement error of a handheld dynamometer., Conclusion: A multitude of measures are used to evaluate neck muscle strength in people with CNP, but their measurement properties have not been fully established. Further methodologically rigorous research is required to increase the overall quality of evidence., (© 2023. The Author(s).)

Background: Movement control tests (MCTs) are clinical tests to evaluate impairment of movement and associated neuromuscular control and are commonly used to evaluate people with neck pain or headache conditions. The aim of this study was to establish inter-rater reliability as well as discriminatory and predictive validity for seven MCTs of the upper (UCS) and lower cervical spine (LCS) in office workers with headache or neck pain., Methods: Seven MCTs of the UCS (3) and LCS (4) were performed at baseline on 140 office workers which were included in a cluster randomized controlled trial. The occurrences of headache and neck pain were established at baseline (discriminatory validity) and at a 15-month follow-up (predictive validity). Inter-rater-reliability was established in a separate cross-sectional study., Results: MCTs showed slight to almost perfect inter-rater reliability but limited discriminatory (baseline) and limited to small predictive validity (15-month follow up) for different subgroups of office workers with headache and/or neck pain. MCTs of the UCS showed limited discriminatory validity, especially for rotation in participants with headache and neck pain compared to those with headache only (Negative Likelihood-ratio: 0.82, 95% CI: 0.69-0.98). Participants with neck pain only and ≥1/4 positive MCTs for the sagittal plane had an increased risk for future neck pain (Relative risk: 3.33, 95% CI: 1.05-10.56)., Discussion: MCTs of the UCS and LCS are reliable but have only limited to small validity to predict future headache events in office workers. Insufficient sagittal plane movement control may predict neck pain relapses in the future., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Although neck pain is known to be a complex and multifactorial condition characterised by the interplay between physical and psychological domains, a comprehensive investigation examining the interactions across multiple features is still lacking. In this study, we aimed to unravel the structure of associations between physical measures of neuromuscular function and fear of movement in people with a history of neck pain. One hundred participants (mean age 33.3 ± 9.4) were assessed for this cross-sectional study, and the neuromuscular and kinematic features investigated were the range of motion, velocity of neck movement, smoothness of neck movement, neck proprioception (measured as the joint reposition error), and neck flexion and extension strength. The Tampa Scale for Kinesiophobia was used to assess fear of movement. A network analysis was conducted to estimate the associations across features, as well as the role of each feature in the network. The estimated network revealed that fear of movement and neuromuscular/kinematic features were conditionally dependent. Higher fear of movement was associated with a lower range of motion, velocity, smoothness of neck movement, neck muscle strength, and proprioception (partial correlations between - 0.05 and - 0.12). Strong interactions were also found between kinematics features, with partial correlations of 0.39 and 0.58 between the range of motion and velocity, and between velocity and smoothness, respectively. The velocity of neck movement was the most important feature in the network since it showed the highest strength value. Using a novel approach to analysis, this study revealed that fear of movement can be associated with a spectrum of neuromuscular/kinematic adaptations in people with a history of neck pain., (© 2022. The Author(s).)

Background: Changes in gait characteristics have been reported in people with chronic neck pain (CNP)., Research Question: Can we classify people with and without CNP by training machine learning models with Inertial Measurement Units (IMU)-based gait kinematic data?, Methods: Eighteen asymptomatic individuals and 21 participants with CNP were recruited for the study and performed two gait trajectories, (1) linear walking with their head straight (single-task) and (2) linear walking with continuous head-rotation (dual-task). Kinematic data were recorded from three IMU sensors attached to the forehead, upper thoracic spine (T1), and lower thoracic spine (T12). Temporal and spectral features were extracted to generate the dataset for both single- and dual-task gait. To evaluate the most significant features and simultaneously reduce the dataset size, the Neighbourhood Component Analysis (NCA) method was utilized. Three supervised models were applied, including K-Nearest Neighbour, Support Vector Machine, and Linear Discriminant Analysis to test the performance of the most important temporal and spectral features., Results: The performance of all classifiers increased after the implementation of NCA. The best performance was achieved by NCA-Support Vector Machine with an accuracy of 86.85%, specificity of 83.30%, and sensitivity of 92.85% during the dual-task gait using only nine features., Significance: The results present a data-driven approach and machine learning-based methods to identify test conditions and features from high-dimensional data obtained during gait for the classification of people with and without CNP., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Objective: Specific neck exercises (SNE) targeting deep cervical flexors and extensors are commonly used for the treatment of nonspecific neck pain (NSNP). However, whether SNE are more effective than alternative exercise interventions (AEI) remains unclear. Furthermore, it has been postulated that SNE may be most effective when they are tailored and targeted to patients with evidence of motor control dysfunction, yet this notion also remains unproven. The objectives of this study were to compare the effectiveness of SNE with that of AEI for reducing pain and disability in people with NSNP and to assess whether the effectiveness of SNE is increased when the exercises are tailored and provided to patients with evidence of motor control dysfunction., Methods: For this systematic review with meta-analysis, Medline, Web of Science, Scopus, and Physiotherapy Evidence Database were searched. Eligibility criteria included randomized controlled trials evaluating the effectiveness of SNE against that of AEI in people with NSNP. Meta-analysis included subgroup analyses to determine the effect of exercise tailoring and participant selection criteria on the effectiveness of SNE., Results: Twelve studies were included. Meta-analysis revealed greater effectiveness of SNE in the short to medium term for reducing pain (pooled standardized mean difference [SMD] = -0.41; 95% CI = -0.76 to -0.06; P = .02) and disability (pooled SMD = -0.41; 95% CI = -0.78 to -0.04; P = .03) but no differences in the long term for pain (pooled SMD = -1.30; 95% CI = -3.35 to 0.75; P = .21) and disability (pooled SMD = -1.81; 95% CI = -4.29 to 0.67; P = .15), although evidence was limited for the latter. The effectiveness of SNE was not superior in studies that included only participants with motor control dysfunction or when exercises were tailored to each participant. Overall, the studies were of low quality. Grading of Recommendations Assessment, Development and Evaluation revealed low certainty, serious risk of bias, and inconsistency of findings for short- to medium-term effects and very low certainty, serious risk of bias, and very serious inconsistency for long-term effects., Conclusion: The preferential use of SNE may be recommended to achieve better short- to medium-term outcomes, although the low quality of evidence affects the certainty of these findings. Currently used strategies for selecting patients and tailoring SNE are not supported by the evidence and therefore cannot be recommended for clinical practice., Impact: SNE are more effective than AEI for reducing pain and disability in patients with NSNP in the short to medium term, but overall evidence is of low quality, affecting the certainty of the findings. Tests of muscle dysfunction (mostly the craniocervical flexion test) currently used in studies to select patients and tailor SNE do not result in greater effectiveness of these exercises., Lay Summary: Evidence suggests SNE are more effective than other forms of exercise, although evidence is overall of low quality. Use of the craniocervical flexion test in isolation to select participants and/or tailor SNE cannot be recommended., (© The Author(s) 2022. Published by Oxford University Press on behalf of the American Physical Therapy Association. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objective: The objective of this study was to synthesize the current evidence regarding the predictive ability of measures of physical function (PF) of the neck region and perceived PF on prognosis following a whiplash injury., Materials and Methods: Electronic databases were searched by 2 independent reviewers up to July 2020, including MEDLINE, EMBASE, CINAHL, PsycINFO, Scopus, and Web of Science as well as gray literature. Eligible studies were selected by 2 reviewers who then extracted and assessed the quality of evidence. Observational cohort studies were included if they involved participants with acute whiplash-associated disorders (WAD), followed for at least 3 months postinjury, and included objective measures of neck PF or self-reported measures of PF as prognostic factors. Data could not be pooled and therefore were synthesized qualitatively., Results: Fourteen studies (13 cohorts) were included in this review. Low to very low quality of evidence indicated that initial higher pain-related disability and higher WAD grade were associated with poor outcome, while there was inconclusive evidence that neck range of motion, joint position error, activity of the superficial neck muscles, muscle strength/endurance, and perceived functional capacity are not predictive of outcome. The predictive ability of more contemporary measures of neck PF such as the smoothness of neck movement, variability of neck motion, and coactivation of neck muscles have not been assessed., Discussion: Although initial higher pain-related disability and higher WAD grade are associated with poor outcome, there is little evidence available investigating the role of neck PF on prognosis following a whiplash injury., Competing Interests: The authors declare no conflict of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Impairments of sensorimotor control relating to head and eye movement control and postural stability are often present in people with neck pain. The upper cervical spine and particularly the obliquus capitis inferior (OCI) play an important proprioceptive role; and its impairment may alter cervical sensorimotor control. Dry needling (DN) is a valid technique to target the OCI., Objectives: To investigate if a single DN session of the OCI muscle improves head and eye movement control-related outcomes, postural stability, and cervical mobility in people with neck pain., Methods: Forty people with neck pain were randomly assigned to receive a single session of DN or sham needling of the OCI. Cervical joint position error (JPE), cervical movement sense, standing balance and oculomotor control were examined at baseline, immediately post-intervention, and at one-week follow-up. Active cervical rotation range of motion and the flexion rotation test were used to examine the global and upper cervical rotation mobility, respectively., Results: Linear mixed-models revealed that the DN group showed a decrease of JPE immediately post-intervention compared to the sham group (mean difference [MD]= -0.93°; 95% confidence interval [CI]: -1.85, -0.02) which was maintained at one-week follow-up (MD= -1.64°; 95%CI: -2.85, -0.43). No effects on standing balance or cervical movement sense were observed in both groups. Upper cervical mobility showed an increase immediately after DN compared to the sham group (MD= 5.14°; 95%CI: 0.77, 9.75) which remained stable at one-week follow-up (MD= 6.98°; 95%CI: 1.31, 12.40). Both group showed an immediate increase in global cervical mobility (MD= -0.14°; 95%CI: -5.29, 4.89)., Conclusion: The results from the current study suggest that a single session of DN of the OCI reduces JPE deficits and increases upper cervical mobility in patients with neck pain. Future trials should examine if the addition of this technique to sensorimotor control training add further benefits in the management of neck pain., Competing Interests: Conflicts of interest None., (Copyright © 2021 Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia. Publicado por Elsevier España, S.L.U. All rights reserved.)

Abstract: To better understand the mechanisms underpinning work-related neck pain, this cross-sectional and single-blinded study compared somatosensory profiles among sonographers with varied neck disability levels. Based on K-mean cluster analysis of scores on the neck disability index (NDI), participants were classified into no (NDI ≤ 8%, n = 31, reference group), mild (NDI = 10%-20%, n = 43), or moderate/severe (NDI ≥ 22%, n = 18) disability groups. Data were collected on bodily pain distribution and severity and psychological measures including depression, anxiety, pain-catastrophizing, and fear-avoidance beliefs using validated scales. Participants attended 1 session of quantitative sensory testing performed according to a standardized protocol, including local and remote thermal and mechanical pain thresholds, temporal summation of pain (TSP), conditioned pain modulation, and an exercise-induced analgesia paradigm. Compared with participants with no and mild disability, those with moderate/severe disability showed more widespread pain, cold and mechanical hyperalgesia at a remote nonpainful site, and significantly higher TSP. Participants with mild disability demonstrated significantly higher TSP than those with no disability. These group differences were attenuated after adjusting for depression or anxiety, indicating these psychological factors may mediate the somatosensory changes associated with neck disability. Group differences were not found for conditioned pain modulation or exercise-induced analgesia. These findings suggest that heightened pain facilitation, rather than impaired pain inhibition may underpin nociplastic pain in participants with moderate/severe disability, and it may be associated with depression and anxiety. Clinicians should be aware that individuals with work-related neck pain presenting with moderate/severe disability display distinct somatosensory features and tailor management strategies accordingly., (Copyright © 2021 International Association for the Study of Pain.)

Neuromuscular impairments are frequently observed in patients with chronic neck pain (CNP). This study uniquely investigates whether changes in neck muscle synergies detected during gait are sensitive enough to differentiate between people with and without CNP. Surface electromyography (EMG) was recorded from the sternocleidomastoid, splenius capitis, and upper trapezius muscles bilaterally from 20 asymptomatic individuals and 20 people with CNP as they performed rectilinear and curvilinear gait. Intermuscular coherence was computed to generate the functional inter-muscle connectivity network, the topology of which is quantified based on a set of graph measures. Besides the functional network, spectrotemporal analysis of each EMG was used to form the feature set. With the use of Neighbourhood Component Analysis (NCA), we identified the most significant features and muscles for the classification/differentiation task conducted using K-Nearest Neighbourhood (K-NN), Support Vector Machine (SVM), and Linear Discriminant Analysis (LDA) algorithms. The NCA algorithm selected features from muscle network topology as one of the most relevant feature sets, which further emphasize the presence of major differences in muscle network topology between people with and without CNP. Curvilinear gait achieved the best classification performance through NCA-SVM based on only 16 features (accuracy: 85.00%, specificity: 81.81%, and sensitivity: 88.88%). Intermuscular muscle networks can be considered as a new sensitive tool for the classification of people with CNP. These findings further our understanding of how fundamental muscle networks are altered in people with CNP., Competing Interests: The authors have declared that no competing interests exist.

People with chronic neck pain (CNP) often present with altered gait kinematics. This paper investigates, combines, and compares the kinematic features from linear and nonlinear walking trajectories to design supervised machine learning models which differentiate asymptomatic individuals from those with CNP. For this, 126 features were extracted from seven body segments of 20 asymptomatic subjects and 20 individuals with non-specific CNP. Neighbourhood Component Analysis (NCA) was used to identify body segments and the corresponding significant features which have the maximum discriminative power for conducting classification. We assessed the efficacy of NCA combined with K- Nearest Neighbour (K-NN), Support Vector Machine and Linear Discriminant Analysis. By applying NCA, all classifiers increased their performance for both linear and nonlinear walking trajectories. Notably, features selected by NCA which magnify the classification power of the computational model were solely from the head, trunk and pelvis kinematics. Our results revealed that the nonlinear trajectory provides the best classification performance through the NCA-K-NN algorithms with an accuracy of 90%, specificity of 100% and sensitivity of 83.3%. The selected features by NCA are introduced as key biomarkers of gait kinematics for classifying non-specific CNP. This paper provides insight into changes in gait kinematics which are present in people with non-specific CNP which can be exploited for classification purposes. The result highlights the importance of curvilinear gait kinematic features which potentially could be utilized in future research to predict recurrent episodes of neck pain., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Introduction: Spinal musculoskeletal conditions, including low back and neck pain, are leading causes of disability globally. The trunk muscles, which comprise muscles in the thoracic and lumbar regions, are essential for functional activities, necessitating mobility, motor control and strength. To investigate the effectiveness of interventions directed at improving trunk muscle strength, it is essential to have valid, reliable and responsive performance-based outcome measures (PBOM). While isokinetic dynamometry is considered the gold-standard PBOM, the associated costs, size/weight and operational complexity of this equipment preclude its use in a clinical setting. There is, therefore, a need to evaluate the measurement properties of alternative accessible measures of trunk strength. This systematic review therefore aims to investigate the measurement properties of PBOM of trunk muscle strength measures appropriate for use in a clinical setting., Methods and Analysis: This protocol has been designed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols. CINAHL, Web of Science, Pedro, MEDLINE, EMBASE, SPORTDiscuss will be searched systematically from the database start date up to 16 April 2020, along with reference checking and the grey literature searching. Eligibility criteria include studies investigating measurement properties of PROM for trunk muscle strength for use in a clinical setting in adults with and without spinal musculoskeletal complaints. Two independent reviewers will determine the eligibility of the studies through screening process of titles, abstract and the full text. Both reviewers will assess the risk of bias using COnsensus-based Standards for the selection of health status Measurement Instruments risk-of-bias tool and then extract the data from included studies. The overall quality of the included studies will be evaluated using the Grading of Recommendations Assessment, Development and Evaluation approach. A narrative synthesis will be carried out if meta-analysis is not applicable. Findings from this systematic review will aid clinicians and practitioners working in the field for example, sport, in using the most appropriate PBOM to measure trunk muscle strength., Ethics and Dissemination: No research ethics application is needed as there are no patient data in this study. The results of this study will be submitted to a peer reviewed journal and presented at conferences., Prospero Registration Number: CRD42020167464., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Measurement of cervical range of motion (ROM) is recommended when physically examining people with neck pain. However, little is known about the clinician's perception of "normal" versus restricted movement. Additionally, it is unknown if an objective measure of restricted movement correlates with the patient's perception of movement restriction., Methods: One hundred patients with neck pain were asked to rate their total amount of restriction, using a movement restriction scale. Two physical therapists (PTs) measured cervical ROM using a CROM device. Assessors independently rated whether the patient was restricted in their cervical ROM for each movement direction ("yes" or "no"). Cohen's kappa was used to assess reliability between both assessor's interpretation for all movement directions. Correlations between the perception of 'normal' versus 'restricted' movement according to both the assessor and patient was compared with an objective classification of movement restriction using normative data., Results: The agreement between PTs was high, ranging from substantial (K: 0.74) to almost perfect (K: 0.94). The correlation between the self-reported restriction scale and objective restriction was 0.44, indicating moderate correlation. The correlation between the PT's interpretation and objective restriction ranged from 0.55 to 0.66 depending on the direction of movement., Conclusion: A large proportion (85%) of the patients with neck pain exhibited restricted cervical ROM, relative to normative data. The agreement between PTs was high in judging whether a patient had restricted cervical ROM. However, the judgement of both the patient and the PT was not always in accordance with the objective measure of movement., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Introduction: Non-specific neck pain (NSNP) is a common musculoskeletal condition resulting in pain, physical limitations and associated functional disability. Current guidelines recommend manipulation and/or mobilisation as part of the multimodal management of NSNP. This study focuses on intervention at the articular level and aims to identify whether joint mobilisation or joint manipulation has a greater effect on function, range of movement or pain outcomes in the management of NSNP., Methods and Analysis: A systematic review protocol has been designed and is reported in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols. A targeted search strategy will enable searching of key databases from inception to 31 March 2020: CINAHL, PEDro, AMED, EMBASE, OVID, MEDLINE, Web of Science, PubMed and Google Scholar. Key journals will be searched using predefined keywords determined from preliminary scoping searches for randomised controlled trials of manipulation and mobilisation modalities for adults with NSNP in the absence of radiculopathy or whiplash, published in English. Grey literature and unpublished studies will also be searched. Studies will be screened by title and abstract and full text. Two independent reviewers will conduct the searches independently, extract data, assess risk of bias (Cochrane Risk of Bias Tool 2) and assess overall strength of evidence (Grading of Recommendations, Assessment, Development and Evaluation). Meta-analysis will be performed where individual studies measure comparable outcomes including performance-based outcome measures such as range of movement or patient reported outcome measures such as Neck Disability Index; and where interventions are comparable in their delivery such as number of oscillations and Maitland grading. Where not possible, data will be presented descriptively., Ethics and Dissemination: This study does not require ethical approval. Findings will be submitted for publication to relevant peer-reviewed journals and will be presented at profession-specific conferences., Prospero Registration Number: CRD42020164457., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Prognostic models play an important role in the clinical management of cervical radiculopathy (CR). No study has compared the performance of modern machine learning techniques, against more traditional stepwise regression techniques, when developing prognostic models in individuals with CR. We analysed a prospective cohort dataset of 201 individuals with CR. Four modelling techniques (stepwise regression, least absolute shrinkage and selection operator [LASSO], boosting, and multivariate adaptive regression splines [MuARS]) were each used to form a prognostic model for each of four outcomes obtained at a 12 month follow-up (disability-neck disability index [NDI]), quality of life (EQ5D), present neck pain intensity, and present arm pain intensity). For all four outcomes, the differences in mean performance between all four models were small (difference of NDI < 1 point; EQ5D < 0.1 point; neck and arm pain < 2 points). Given that the predictive accuracy of all four modelling methods were clinically similar, the optimal modelling method may be selected based on the parsimony of predictors. Some of the most parsimonious models were achieved using MuARS, a non-linear technique. Modern machine learning methods may be used to probe relationships along different regions of the predictor space.

Background: Several studies have analysed the activity of superficial neck flexors, but the activity of neck extensors has been less investigated in patients with neck pain OBJECTIVES: 1, to investigate the differences in the activation of superficial neck flexor and extensor musculature during the cranio-cervical flexion test (CCFT) in women with mechanical chronic neck pain when compared to asymptomatic women; 2, to investigate the correlation between neck muscle activity and the clinical features of neck pain DESIGN: Cross-sectional METHODS: Surface electromyography was recorded bilaterally from the sternocleidomastoid, anterior scalene, splenius capitis, and upper trapezius muscles of 30 women with mechanical chronic neck pain and 30 asymptomatic women as they performed the CCFT. Comparisons of the normalized root mean square between both groups were conducted with 2x5 ANCOVA with task level as the within-subjects variable, group as the between-subjects variable, and pain related-disability as a co-variate RESULTS: Women with mechanical neck pain exhibited increased activity of superficial neck flexors (sternocleidomastoid: F = 14.448, P < 0.001; anterior scalene: F = 21.693, P < 0.001) and superficial neck extensors (splenius capitis: F = 4.692, P < 0.001; upper trapezius: F = 4.245, P < 0.001) as compared to asymptomatic women. Higher pain related-disability was associated with more electrical activity of the anterior scalene and upper trapezius muscles during the CCFT CONCLUSIONS: Women with mechanical chronic neck pain exhibit an increased activity of their superficial neck flexors and superficial neck extensors during a low-load task such as CCFT when compared to asymptomatic pain-free women. Our results should be considered when designing therapeutic exercise programs for this population., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Chronic Neck Pain (CNP) can be associated with biomechanical changes. This paper investigates the changes in patterns of walking kinematics along a curvilinear trajectory and uses a specially designed feature space, coupled with a machine learning framework to conduct a data-driven differential diagnosis, between asymptomatic individuals and those with CNP. For this, 126 kinematic features were collected from seven body segments of 40 participants (20 asymptomatic, 20 individuals with CNP). The features space was processed through a Neighbourhood Component Analysis (NCA) algorithm to systematically select the most significant features which have the maximum discriminative power for conducting the differential diagnosis. The selected features were then processed by a K-Nearest Neighbors (K-NN) classifier to conduct the task. Our results show that, through a systematic selection of feature space, we can significantly increase the classification accuracy. In this regard, a 35% increase is reported after applying the NCA. Thus, we have shown that using only 13 features (of which 61% belong to kinematic features and 39% to statistical features) from five body segments (Head, Trunk, Pelvic, Hip and Knee) we can achieve an accuracy, sensitivity and specificity of 82.50%, 80.95% and 84.21% respectively. This promising result highlights the importance of curvilinear kinematic features through the proposed information processing pipeline for conducting differential diagnosis and could be tested in future studies to predict the likelihood of people developing recurrent neck pain.

Objective: Utilizing shear wave elastography, we compared the stiffness of the neck extensor muscles and the stiffness in muscle-specific regions between women with chronic nonspecific neck pain and asymptomatic controls., Design: Cross-sectional observational study., Methods: We measured the average muscle stiffness over multiple neck extensor muscles and in regions corresponding approximately to the trapezius, splenius capitis, semispinalis capitis, semispinalis cervicis, and multifidus muscles using ultrasound shear wave elastography in 20 women with chronic nonspecific neck pain and 18 asymptomatic women during multiple tasks. The measurements were automatically quality controlled and computer processed over the complete visible neck region or a large muscle-specific region., Results: Pooled over all tasks, neck muscle stiffness was not significantly different between those with neck pain and asymptomatic controls (neck pain median, 11.6 kPa; interquartile range, 8.9 kPa and control median, 13.3 kPa; interquartile range, 8.6 kPa; P = .175). The measure of neck muscle stiffness was not correlated with the intensity of neck pain or perceived disability., Conclusion: Shear wave elastography revealed similar muscle stiffness in people with and without chronic neck pain, despite the sensation of increased neck stiffness in those with chronic neck pain. Therapeutic interventions aiming to reduce neck muscle tone are often based on the assumption that perceived neck stiffness corresponds to objective muscle stiffness. The current results question this assumption. J Orthop Sports Phys Ther 2020;50(4):179-188. Epub 6 Jan 2020. doi:10.2519/jospt.2020.8821 .

Background: Although the reliability of pain drawings (PDs) has been confirmed in people with chronic pain, there is a lack of evidence about the validity of the PD, that is, does the PD accurately represent the pain experience of the patient?, Objectives: We investigate whether people with chronic neck pain (CNP) can recognize their own PD to support the validity of the PD in reporting the experience of pain. Moreover, we examined the association between their ability to recognize their own PD with their levels of pain intensity and disability and extent of psychosocial and somatic features., Study Design: Experimental., Setting: University Laboratory., Methods: Individuals with CNP completed their PD on a digital body chart, which was then automatically modified with specific dimensions using a novel software, providing an objective range of distortion and eliminating errors, which could potentially occur in manually controlled visual-subjective based methods. Following a 10-minute break listening to music, a series of 20 PDs were presented to each patient in a random order, with only 2 being their original PD. For each PD, the patients rated its likeliness to their own original PD on a scale from 0 to 100, with 100 representing "this is my pain.", Results: Overall, the patients rated their original PD with a median score of 92% similarity, followed by 91.8% and 89.5% similarity when presented with a PD scaled down to 75% and scaled up by 150% of the original size, respectively; these scores were not significantly different to the ratings given for their original PD. The PD with horizontal translation by 40 pixels (8%) and vertical translation by 70 pixels (12.8%) were rated as the most dissimilar to their original PD; these scores were significantly different to their original PD scores. The Spearman correlation coefficient revealed a significant negative association between their ability to recognize their original PD and their Modified Somatic Perceptions Questionnaire scores., Limitations: The patients in the study presented with relatively mild CNP, and the results may not be generalized to those with more severe symptoms., Conclusions: People with CNP are generally able to identify their own PD but that their ability to recognize their original PD is negatively correlated with the extent of somatic awareness., Key Words: Chronic pain, perception, pain drawings, somatic awareness.

Background: Previous findings reported that people with chronic neck pain walk with reduced range trunk rotation, especially when walking in more challenging conditions. Quantification of the quality of neck and trunk movement during gait could provide further insight into biomechanical changes that occur in people with neck pain. This study uniquely compared the variability of trunk and neck rotation during single-task and dual-task gait in people with chronic neck pain and asymptomatic individuals., Methods: An observational case-control study was conducted on 20 asymptomatic individuals and 24 people with chronic neck pain of idiopathic or traumatic origin. Participants performed rectilinear walking whilst keeping the head in a neutral position (single-task) and whilst rotating the head at a natural speed (dual-task). Trunk and head rotation angles were averaged across gait cycles for the task trials. The data were normalised in time, and the average variability of angular distribution along the normalised cycle was extracted. The Tampa Scale for Kinesiophobia was used to assess fear of movement., Findings: During single-task gait, there were no group differences for the variability of trunk (p = 0.862) or neck (p = 0.427) rotation. For dual-task gait, there was no difference between groups for the variability of neck rotation (p = 0.636), however, the participants with neck pain displayed reduced variability of trunk rotation (p = 0.021). The neck pain group also walked at a significantly slower speed during dual-task gait (p = 0.043) compared to asymptomatic individuals and the speed of their gait was associated with the extent of fear of movement., Interpretation: The strategy observed in participants with chronic neck pain likely reflects adaptive behaviour when faced with more challenging conditions for postural control., Competing Interests: Declaration of competing interest None., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Introduction: The course of spinal pain (neck or low back pain) is often described as episodic and intermittent, with more than one-third of people continuing to experience episodic symptoms 1 year after first onset. Although ongoing neuromuscular adaptations could contribute to recurrent episodes of pain, no systematic review has synthesised evidence of ongoing neuromuscular changes in people with recurrent spinal pain during a period of symptom remission., Methods and Analysis: This protocol is developed and reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses-P, the Update of the Cochrane Back and Neck Group guidelines and the Methodological Expectations of Cochrane Intervention Reviews. PubMed, Web of Science, MEDLINE, EMBASE, CINAHL, ZETOC, Google Scholar, grey literature sources and key journals will be searched up to September 2019. Observational studies investigating neuromuscular changes in people with recurrent spinal pain during a period of remission will be included. Neuromuscular function will be considered under five outcome domains of muscle activity, spine kinematics, muscle properties, sensorimotor control and neuromuscular performance. Two independent reviewers will search, screen studies, extract data and assess risk of bias (Newcastle-Ottawa Scale). Data will be synthesised per outcome domain. Where clinical and methodological homogeneity across studies exists, a random-effects meta-analysis will be conducted. Otherwise, results will be synthesised narratively. The overall quality of evidence will be assessed using the Grading of Recommendations, Assessment, Development and Evaluation guidelines., Ethics and Dissemination: Findings of this review may aid the identification of factors that could contribute to spinal pain recurrence and aid the development of interventions for secondary prevention aimed at the restoration of optimal neuromuscular function. The results will be submitted for publication in a peer-reviewed journal and presented at conferences. No ethical approval was required., Prospero Registration Number: CRD42019141527., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Introduction: Mitigating the transition from acute to chronic whiplash-associated disorders (WAD) is fundamental, and this could be achieved through early identification of individuals at risk. Several physical factors such as angular velocity, smoothness of neck movement and coactivation of neck flexors and extensors, have been observed in patients with WAD, but their predictive ability after a whiplash injury have not been considered in previous reviews. Therefore, the aim of the current protocol is to outline the protocol for a systematic review that synthesises the current evidence of which physical factors can predict ongoing pain and disability following a whiplash trauma., Methods and Analysis: Two independent reviewers will search for studies in several electronic databases including MEDLINE, Embase, CINAHL, PsycINFO, Scopus and Web of Science as well as grey literature. Observational cohort studies will be considered if they involve participants with acute WAD followed for at least 3 months post-injury. Studies will be required to assess the prognostic ability of one or more physical factors that directly involve a body function and/or structure and can be measured objectively. Further, patient-reported outcomes of physical function will be considered. The primary outcome for this review is Neck Disability Index, while all other validated measures will be considered as secondary outcomes. Risk of bias across individual studies will be assessed using the Quality In Prognostic Studies tool along with the Grades of Recommendation, Assessment, Development and Evaluation method to assess the quality of evidence. A meta-analysis will be conducted depending on homogeneity and the number of available studies. If appropriate, data will be pooled and presented as odds ratios, otherwise, a qualitative synthesis will be conducted., Ethics and Dissemination: Ethical approval is not required for this systematic review. The result from this review will be published in peer-reviewed journals., Prospero Registration Number: CRD42019122559., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Recent work described parameters of the helical axis in asymptomatic people with potential for investigating kinematic changes in the cervical region. This approach could provide novel information on movement variability in people with neck pain, however this has never been investigated. This study aimed to investigate movement variability during active neck movements performed at different speeds in people with and without chronic neck pain., Methods: This observational case-control study examined 18 participants with chronic neck pain of either idiopathic or traumatic origin and 18 gender-matched asymptomatic participants. Cervical kinematics were captured with 3D motion capture as people with and without chronic neck pain performed flexion-extension, bilateral lateral flexion and bilateral rotation at different speeds (natural, slow, and fast). The mean distance and mean angle parameters of the helical axis were extracted to describe 3D motion and quantify movement variability., Findings: A smaller mean distance was observed in those with neck pain compared to the asymptomatic participants during flexion-extension (P = 0.019) and rotation movements (P = 0.007). The neck pain group displayed smaller values for the mean angle during rotation movements with different speeds (P = 0.01). These findings indicate less variable movement for those with neck pain relative to the asymptomatic participants. No difference in the mean angle was observed between groups for flexion-extension and lateral flexion., Interpretation: The findings reiterate the importance of data derived from kinematic measures, and its potential for providing clinicians with further insight into the quality of active neck movements in people with chronic neck pain., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: Neck pain is presented with a variety of symptoms. Pain drawings are used in the clinical assessment of people with neck pain. Pain extent based upon pain drawings can be associated with different factors. However, the relation between pain extent and function limitations in people with neck pain is unknown., Aim: The aim of this study was to explore the associations between pain extent extracted from pain drawings, and self-reported neck pain related disability, quality of life, depression, self-reported neck function, cervical muscle function, and range of motion in a chronic neck pain population and possible differences depending on the onset of pain being traumatic or not., Design: Observational cross-sectional study., Setting: Primary and secondary healthcare., Population: People with chronic neck pain (N.=200) of traumatic (N.=120) or non-traumatic (N.=80) origin., Methods: Outcome measures: Pain extent, Short Form 36 Health Survey Physical and Mental Component Summary (SF36-PCS/MCS), TAMPA Scale of Kinesiophobia (TSK), Beck Depression Inventory-II (BDI-II), Neck Disability Index (NDI), Craniocervical Flexion Test (CCFT), Cervical Extension Test (CE), and Cervical Range of Motion (ROM). Correlations were calculated using Spearman or Pearson correlation coefficients. Correlation between pain extent and outcomes were calculated for all participants collectively and then separately for those with a traumatic versus non-traumatic neck pain., Results: Overall, significant positive correlations were observed between pain extent and NDI (r=0.33; P<0.001), BDI-II (r=0.29; P<0.001), CCFT (r=-0.24; P=0.001) and CE (r=-0.19; P=0.006). No difference was observed in pain extent between patients with traumatic (mean: 7.6±6.7%) and non-traumatic onset (7.4±6.8%). Pain extent correlated moderately with NDI, BDI-II, TSK, CCFT and CE in those with non-traumatic onset, but weakly with NDI, BDI-II, CCFT and CE in those with trauma-induced chronic neck pain., Conclusions: Pain extent is correlated with patient-reported neck function, depression and muscle test performance in people with chronic neck pain. These correlations were strongest in those with non-traumatic neck pain., Clinical Rehabilitation Impact: Patients presenting with larger pain areas show poorer psychological and physical function. Pain drawings can therefore indicate a need for addressing these functions in management of a person with chronic neck pain.

Study Design Longitudinal clinimetric study. Background Pain self-efficacy predicts poor recovery and mediates the relationship between pain and disability in patients with neck pain disorders (NPDs). The Pain Self-Efficacy Questionnaire (PSEQ) is a frequently used instrument to measure pain self-efficacy; however, its measurement properties have never been evaluated in a group of patients with NPDs. Objectives This study aimed to assess validity and responsiveness of the PSEQ in patients with NPDs. Methods Patients with NPDs (n = 161) were included. Confirmatory and exploratory factor analysis was used to assess structural validity. Twelve hypotheses on expected correlations with other instruments were formulated a priori to assess construct validity. Responsiveness was evaluated in 146 patients with NPDs who underwent multimodal rehabilitation by testing 12 hypotheses on expected effect sizes, area under the curve, and correlations with change in other instruments. Results Factor analyses showed that the PSEQ is a unidimensional instrument with moderate construct validity and responsiveness (50% to 75% of hypotheses met). Validity was consistent when analyzed separately for patients with whiplash-associated disorders and idiopathic neck pain, and responsiveness was better in patients with idiopathic neck pain. Conclusion The PSEQ is a unidimensional measure of pain self-efficacy in patients with NPDs, as found by previous studies in other populations. Nevertheless, in contrast with previous studies, its construct validity and responsiveness were found to be suboptimal in NPDs, suggesting that the content validity of the PSEQ and of the comparator instruments used in this study should be better assessed. J Orthop Sports Phys Ther 2018;48(3):204-216. Epub 19 Dec 2017. doi:10.2519/jospt.2018.7605.

Background: Impaired cervical joint position sense and balance are associated with neck pain. Specific therapeutic exercise and manual therapy are effective for improving neck pain and functional ability but their effects on joint position sense and balance impairments remain uncertain. Changes in the joint position sense and balance may need to be addressed specifically. The primary objective is to investigate the most effective interventions to improve impaired cervical joint position sense and balance in individuals with neck pain. The secondary objective is to assess the effectiveness of the interventions on pain intensity and disability, pain location, dizziness symptoms, cervical range of motion, gait speed, functional ability, treatment satisfaction and quality of life., Methods: A 2 × 2 factorial, single blind RCT with immediate, short- and long-term follow-ups. One hundred and sixty eight participants with neck pain with impaired joint position sense and balance will be recruited into the trial. Participants will be randomly allocated to one of four intervention groups: i) local neck treatment, ii) local treatment plus tailored sensorimotor exercises, iii) local treatment plus balance exercises, and iv) local treatment plus sensorimotor and balance exercises. Participants receive two treatments for 6 weeks. Primary outcomes are postural sway and cervical joint position error. Secondary outcomes include gait speed, dizziness intensity, neck pain intensity, neck disability, pain extent and location, cervical range of motion, functional ability, perceived benefit, and quality of life. Assessment will be measured at baseline, immediately after treatment and at 3, 6, 12 month-follow ups., Discussion: Neck pain is one of the major causes of disability. Effective treatment must address not only the symptoms but the dysfunctions associated with neck pain. This trial will evaluate the effectiveness of interventions for individuals with neck pain with impaired cervical joint position sense and balance. This trial will impact on clinical practice by providing evidence towards optimal and efficient management., Trial Registration: ClinicalTrials.gov ( NCT03149302 ). May 10, 2017.

Background and Aims: According to existing literature, musicians are at risk of experiencing a range of painful musculoskeletal conditions. Recently, a novel digital technology was developed to investigate pain location and pain extent. The aim of this study was to describe pain location and pain extent in musicians using a digital method for pain drawing (PD) analysis. Additionally, the association between PD variables and clinical features were explored in musicians with pain., Methods: One hundred and fifty-eight musicians (90 women and 68 men; aged 22.4 ± 3.6 years) were recruited from Swiss and U.K. conservatories. Participants were asked to complete a survey including both background musical information and clinical features, the QuickDASH (QD) questionnaire, and the digital PDs., Results: Of the 158 participants, 126 musicians (79.7%) reported having pain, with higher prevalence in the areas of the neck and shoulders, the lower back, and the right arm. The mean percentage of pain extent was 3.1% ± 6.5%. The mean QD score was higher for musicians with pain than for those without pain. Additionally, the results indicated a positive correlation between the QD score and pain extent, and there were significant correlations between age and pain intensity, as well as between pain extent and pain intensity., Conclusions: The high prevalence of pain among musicians has been confirmed using a digital technique for PD acquisition and analysis. In addition, positive correlations between pain extent and upper limb disability have been demonstrated. Our findings highlight the need for effective prevention and treatment strategies for musicians., (© 2017 The Authors. Pain Practice published by Wiley Periodicals, Inc. on behalf of World Institute of Pain.)

Background: Responsiveness of a clinical test is highly relevant in order to evaluate the effect of a given intervention. However, the responsiveness of clinical tests for people with neck pain has not been adequately evaluated. The objective of the present study was to examine the responsiveness of four clinical tests which are low cost and easy to perform in a clinical setting, including the craniocervical flexion test, cervical active range of movement, test for the cervical extensors and pressure pain threshold testing., Methods: This study is a secondary analysis of data collected in a previously published randomised controlled trial. Participants were randomized to either physical training, exercises and pain education combined or pain education only. Participants were tested on the clinical tests at baseline and at 4-month follow-up. An anchor-based approach using Receiver Operator Characteristics (ROC) curves was used to evaluate responsiveness of the clinical tests. The Neck Disability Index was used to discriminate between those who had improved and those who were unchanged at the 4-month follow-up. Minimum Clinically Important Difference (MCID), together with sensitivity, specificity, positive and negative predictive values, in addition to positive and negative likelihood ratios were calculated., Results: In total, 164 participants completed the 4 month follow up. One-hundred forty four participants were classified as unchanged whereas 20 patients were considered to be improved. Twenty-six participants didn't complete all of the clinical tests, leaving a total of 138 to be included for analyses. Area Under Curve (AUC) ranged from 0.50-0.62 for the clinical tests, and were all below an acceptable level. MCID was generally large, and the corresponding sensitivity and specificity was low with sensitivity ranging from 20 to 60%, and specificity from 54 to 86%. LR+ (0.8-2.07) and LR- (0.7-1.1) showed low diagnostic value for all variables, with PPV ranging from 12.1 to 26.1 and NPV ranging from 84.7 to 89.2., Conclusion: Responsiveness of the included clinical tests was generally low when using change in NDI score as the anchor from baseline to the 4-month follow up. Further investigations of responsiveness are warranted, possibly using other anchors, which to a higher degree resemble similar dimensions as the clinical tests.

Study Design: Quasi-Experimental., Objective: To assess the activation of semispinalis cervicis (d-SSC) and splenius capitis (s-SC) muscles, and the activation between the two during neck pulley and free weight exercises., Background: Altered activation of cervical extensors may occur with neck pain, suggesting that exercises should be designed to target these muscles., Methods: d-SSC and s-SC activity was recorded unilaterally with intramuscular electromyography from healthy volunteers during cervical isometric exercises: 1) extension with a pulley rope angled from incline to vertical, 2) extension with right, left and central forehead hanging weight, and 3) rotation with pulley rope angled from incline to decline., Results: Extension against a vertical force led to greater activation of d-SSC (P < 0.001) and s-SC (P < 0.001) compared to the inclined, declined and horizontal pulley. With each of these conditions, amplitude of muscle activity was higher for the d-SSC compared to the s-SC muscle (P < 0.0001). Extension with free weight hanging on right, left or central forehead, showed no differences across conditions, although in each condition, the d-SSC amplitude was higher than the s-SC. For cervical rotation, the declined pulley led to the greatest activation of both muscles (P < 0.05). Higher levels of activity were observed for the s-SC compared to the d-SSC (P < 0.01) for all rotation conditions., Conclusion: A vertical resistance during an extension exercise or a declined resistance during cervical rotation, increased neck extensor activation. The results from this preliminary study provide guidance for future work on the exploration and development of low-load exercise design for patients with neck pain disorders., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Study Design Controlled laboratory study, case-control design. Objective To evaluate spine kinematics and gait characteristics in people with nonspecific chronic neck pain. Background People with chronic neck pain present with a number of sensorimotor and biomechanical alterations, yet little is known about the influence of neck pain on gait and motions of the spine during gait. Methods People with chronic nonspecific neck pain and age- and sex-matched asymptomatic controls walked on a treadmill at 3 different speeds (self-selected, 3 km/h, and 5 km/h), either with their head in a neutral position or rotated 30°. Tridimensional motion capture was employed to quantify body kinematics. Neck and trunk rotations were derived from the difference between the transverse plane component of the head and thorax and thorax and pelvis angles to provide an indication of neck and trunk rotation during gait. Results Overall, the patient group showed shorter stride length compared to the control group (P<.001). Moreover, the patients with neck pain showed smaller trunk rotations (P<.001), regardless of the condition or speed. The difference in the amount of trunk rotation between groups became larger for the conditions of walking with the head rotated. Conclusion People with chronic neck pain walk with reduced trunk rotation, especially when challenged by walking with their head positioned in rotation. Reduced rotation of the trunk during gait may have long-term consequences on spinal health. J Orthop Sports Phys Ther 2017;47(4):268-277. Epub 3 Feb 2017. doi:10.2519/jospt.2017.6768.

Objectives: To characterize the distribution of masseter muscle activity and force control during bilateral jaw clenching tasks in people with chronic nonspecific neck pain, without an associated temporomandibular disorder., Methods: Twelve volunteers with nonspecific neck pain and 12 age-matched and sex-matched healthy individuals participated. Submaximal symmetrical and asymmetrical bilateral jaw clenching was performed with and without visual feedback of force. Force performance was assessed with indices of accuracy (mean distance, offset error) and precision (standard deviation, coefficient of variation of force). High-density, 2-dimensional, surface electromyography (EMG) was recorded to characterize bilateral masseter muscle activity. The EMG root mean square was computed for each location of the electrode grid to form a map of the EMG amplitude distribution, and the location of the center of activity was measured., Results: The patient group showed a different distribution of masseter muscle activity compared with pain-free individuals during both symmetrical and asymmetrical bilateral jaw clenching. The position of the center of activity was positioned more cranial (P<0.001; right masseter only) and more anteriorly in the patient group (P<0.0001). In addition, the patients with chronic neck pain displayed higher levels of masseter muscle activation compared with the control participants regardless of the specific task performed (P<0.0001)., Discussion: People with chronic neck pain display increased activation and altered distribution of masseter muscle activity during a jaw-clenching coordination task. These results provide a greater appreciation of how secondary orofacial pain or temporomandibular disorders may develop in people with neck pain.

Background: The craniocervical flexion test assesses the deep cervical flexor muscles (longus capitis, longus colli). Ideally, electromyography (EMG) studies measure activity in both deep and superficial (sternocleidomastoid, anterior scalene) flexors during the test, but most studies confine recordings to superficial muscle activity as the technique to record the deep muscles is invasive. Higher activity of the superficial flexors has been interpreted as an indicator of reduced deep flexor activity in people with neck pain but how close the inverse relationship is during this test is unknown., Methods: EMG was recorded from the sternocleidomastoid, anterior scalene and deep cervical flexor muscles to quantify their relationship during the craniocervical flexion test, from 32 women (age: 38.0 ± 11.6 yrs) with a history of chronic non-specific neck pain. The range of craniocervical flexion at each of the five test stages was also measured., Results: A moderate negative correlation was identified (r = -0.45; P < 0.01) between the average normalized EMG amplitude of the deep cervical flexors and sternocleidomastoid across all stages of the craniocervical flexion test. There was a moderate although weaker and non-significant negative correlation between deep cervical flexors and anterior scalene activity (r = -0.34; P = 0.053)., Conclusions: The results affirm the interpretation that higher levels of activity of the superficial flexor muscles are an indicator of reduced deep cervical flexor activity in the craniocervical flexion test. Further studies of neuromuscular and movement strategies used by people with neck pain to compensate for poorer activation of the deep cervical flexors will inform best clinical assessment., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Chronic neck pain attributed to a myofascial pain syndrome is characterized by the presence of muscle contractures referred to as myofascial trigger points. In this randomized, parallel-group, blinded, controlled clinical trial, we examined the effectiveness of deep dry needling (DDN) of myofascial trigger points in people with chronic nonspecific neck pain. The study was conducted at a public Primary Health Care Centre in Madrid, Spain, from January 2010 to December 2014. A total of 130 participants with nonspecific neck pain presenting with active myofascial trigger points in their cervical muscles were included. These participants were randomly allocated to receive: DDN plus stretching (n = 65) or stretching only (control group [n = 65]). Four sessions of treatment were applied over 2 weeks with a 6-month follow-up after treatment. Pain intensity, mechanical hyperalgesia, neck active range of motion, neck muscle strength, and perceived neck disability were measured at baseline, after 2 sessions of intervention, after the intervention period, and 15, 30, 90, and 180 days after the intervention. Significant and clinically relevant differences were found in favour of dry needling in all the outcomes (all P < 0.001) at both short and long follow-ups. Deep dry needling and passive stretching is more effective than passive stretching alone in people with nonspecific neck pain. The results support the use of DDN in the management of myofascial pain syndrome in people with chronic nonspecific neck pain.

Objective: To compare the effects of cranio-cervical flexion vs cervical proprioception training on neuromuscular control, pressure pain sensitivity and perceived pain and disability in patients with chronic neck pain., Methods: Twenty-eight volunteers with chronic non-specific neck pain were randomly assigned to 1 of 2 interventions and undertook 6 physiotherapist-supervised sessions over a period of 2 months. Both groups performed daily home exercise. Performance on the cranio-cervical flexion test, pressure pain thresholds and reported levels of pain and disability were measured before and immediately after the first treatment session, 1 month after starting treatment and 2 months after starting treatment (at completion of the intervention)., Results: At 2 months, both groups improved their performance on the cranio-cervical flexion test (p < 0.05), but this did not differ between groups (p > 0.05). Both groups showed a reduction in their pain at rest and disability at 2 months, but this was also not different between groups (p > 0.05). Pressure pain sensitivity did not change for either group., Conclusion: Both specific cranio-cervical flexion training and proprioception training had a comparable effect on performance on the cranio-cervical flexion test, a test of the neuromuscular control of the deep cervical flexors. These results indicate that proprioception training may have positive effects on the function of the deep cervical flexors.

A motor task can be performed via different patterns of muscle activation that show regularities that can be factorized in combinations of a reduced number of muscle groupings (also referred to as motor modules, or muscle synergies). In this study we evaluate whether an acute noxious stimulus induces a change in the way motor modules are combined to generate movement by neck muscles. The neck region was selected as it is a region with potentially high muscular redundancy. We used the motor modules framework to assess the redistribution of muscular activity of 12 muscles (6 per side) in the neck region of 8 healthy individuals engaged in a head and neck aiming task, in non-painful conditions (baseline, isotonic saline injection, post pain) and after the injection of hypertonic saline into the right splenius capitis muscle. The kinematics of the task was similar in the painful and control conditions. A general decrease of activity was noted for the injected muscle during the painful condition together with an increase or decrease of the activity of the other muscles. Subjects did not adopt shared control strategies (motor modules inter subject similarity at baseline 0.73±0.14); the motor modules recorded during the painful condition could not be used to reconstruct the activation patterns of the control conditions, and the painful stimulus triggered a subject-specific redistribution of muscular activation (i.e., in some subjects the activity of a given muscle increased, whereas in other subjects it decreased with pain). Alterations of afferent input (i.e., painful stimulus) influenced motor control at a multi muscular level, but not kinematic output. These findings provide new insights into the motor adaptation to pain.

Aim: To assess whether patients with persistent neck pain display evidence of altered masticatory muscle behavior during a jaw-clenching task, despite the absence of orofacial pain or temporomandibular disorders., Methods: Ten subjects with persistent, nonspecific neck pain and 10 age- and sex-matched healthy controls participated. Maximal voluntary contractions (MVCs) of unilateral jaw clenching followed by 5-second submaximal contractions at 10%, 30%, 50%, and 70% MVC were recorded by two flexible force transducers positioned between the first molar teeth. Task performance was quantified by mean distance and offset error from the reference target force as error indices, and standard deviation of force was used as an index of force steadiness. Electromyographic (EMG) activity was recorded bilaterally from the masseter muscle with 13 X 5 grids of electrodes and from the anterior temporalis with bipolar electrodes. Normalized EMG root mean square (RMS) was computed for each location of the grid to form a map of the EMG amplitude distribution, and the average normalized RMS was determined for the bipolar acquisition. Between-group differences were analyzed with the Kruskal Wallis analysis of variance., Results: Task performance was similar in patients and controls. However, patients displayed greater masseter EMG activity bilaterally at higher force levels (P<.05)., Conclusion: This study has provided novel evidence of altered motor control of the jaw in people with neck pain despite the absence of orofacial pain or temporomandibular disorders.

Background: The reliability of clinical tests for the cervical spine has not been adequately evaluated. Six cervical clinical tests, which are low cost and easy to perform in clinical settings, were tested for intra- and inter-examiner reliability, and two performance tests were assessed for test-retest reliability in people with and without chronic neck pain. Moreover, construct and between-group discriminative validity of the tests were examined., Methods: Twenty-one participants with chronic neck pain and 21 asymptomatic participants were included. Intra- and inter-reliability were evaluated for the Cranio-Cervical Flexion Test (CCFT), Range of Movement (ROM), Joint Position Error (JPE), Gaze Stability (GS), Smooth Pursuit Neck Torsion Test (SPNTT), and neuromuscular control of the Deep Cervical Extensors (DCE). Test-retest reliability was assessed for Postural Control (SWAY) and Pressure Pain Threshold (PPT) over tibialis anterior, infraspinatus and the C3-C4 segment., Results: Intraclass Correlation Coefficient (ICC) for intra- and inter-examiner reliability was highest for ROM (range: 0.80 to 0.94), DCE (0.75 to 0.90) and CCFT (0.63 to 0.86). JPE had the lowest ICC (0.02 to 0.66). Intra- and inter-reliability for GS and SPNTT showed kappa ranging from 0.66 to 0.92, and 0.57 to 0.78 (prevalence adjusted), respectively. For the test-retest study, ICC was 0.83 to 0.89 for PPT and 0.39 to 0.79 for SWAY. Construct validity was satisfactory for all tests, except JPE. Significant between group discriminative validity was found for CCFT, ROM, GS, SPNTT and PPT, however, differences were within the limits of the minimal detectable change., Conclusions: The majority of the tests evaluated showed satisfactory reliability and construct validity supporting their use in the clinical evaluation of patients with chronic neck pain.

Objective: The purpose of this study was to investigate the effect of active vs passive scapular correction on pain and pressure pain threshold at the most symptomatic cervical segment in patients with chronic neck pain., Methods: Twenty-three volunteers with chronic, idiopathic neck pain were recruited (age, 38.9 ± 14.4 years; sex [man/woman], 3/20; Neck Disability Index, 28.1% ± 9.9%). Subjects were randomly allocated to 2 groups: active scapular correction or passive scapular correction. Pressure pain threshold and pain intensity rated on a numerical rating scale during a posteroanterior glide over the most symptomatic cervical segment were measured before and immediately after the active or passive scapular intervention., Results: Only the active scapular correction produced a reduction in pain (pre, 6.3 ± 1.2; post, 3.7 ± 2.4; P < .05) and increase in pressure pain threshold (pre, 8.7 ± 4.2 kg/cm(2); post, 10.1 ± 3.8 kg/cm(2); P < .05) at the most painful cervical segment., Conclusions: An active scapular correction exercise resulted in an immediate reduction of pain and pressure pain sensitivity in patients with chronic neck pain and scapular dysfunction., (Copyright © 2014 National University of Health Sciences. Published by Elsevier Inc. All rights reserved.)

The aim of this study was to assess the activation of the sternocleidomastoid (SCM) and splenius capitis (SC) muscles in response to unanticipated, full body perturbations in individuals with chronic neck pain (NP) and age-matched healthy controls (HC). Individuals with NP had a history of NP for 8.9 ± 7.8 years, rated the intensity of NP as 4.2 ± 2.0 (score out of 10), and scored 15.3 ± 6.5 on the Neck Disability Index. Participants stood on a moveable platform during which 32 randomized postural perturbations (eight repetitions of four perturbation types: 8 cm forward slide (FS), 8 cm backward slides, 10° forward tilt, and 10° backward tilt) with varying inter-perturbation time intervals were performed over a period of 5 min. Bilateral surface electromyography (EMG) from the SCM and SC was recorded, and the onset time and the average rectified value of the EMG signal was determined for epochs of 100 ms; starting 100 ms prior to and 500 ms after the perturbation onset. Individuals with NP, as compared to HC, demonstrated delayed onset times and reduced EMG amplitude of the SCM and SC muscles in response to all postural perturbations. Such findings were most pronounced following the FS postural perturbation (healthy vs. NP for SCM 83.3 ± 8.0 vs. 86.3 ± 4.4 and SC 75.6 ± 3.5 vs. 89.3 ± 4.2), which was also associated with the greatest change (expressed in % relative to baseline) in EMG amplitude (healthy vs. NP for SCM 206.6 ± 50.4 vs. 115.9 ± 15.7 and SC 83.4 ± 19.2 vs. 69.2 ± 10.9) across all postural perturbations types. Individuals with NP display altered neural control of the neck musculature in response to rapid, unanticipated full body postural perturbations. Although the relative timing of neck musculature activity in individuals with NP appears to be intact, simultaneous co-activation of the neck musculature emerges for unanticipated anterior-posterior postural perturbations.