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Objectives: Neck-specific exercise can reduce neck pain and increase function, but information on how different neck muscle layers are activated during neck exercises is scarce. The aim of this study was to investigate deformation and deformation rate in 5 dorsal neck muscles and the correlation among these muscles during a loaded dynamic exercise used in clinical practice., Methods: Deformation and deformation rate were investigated in 5 dorsal right-sided neck muscles in 20 individuals without neck pain using ultrasonography and speckle-tracking analyses. Repeated-measures analysis of variance was used to measure differences between the muscles, and correlations between neck muscles were analyzed with Kendall's tau., Results: Deformation in left (contralateral) rotation showed significant differences among the muscles (P = .01), with higher deformation of the semispinalis capitis muscle compared with the trapezius muscle (P = .02). There were no significant differences among the 5 neck muscles in right (unilateral) rotation (P = .46). There were significant differences in deformation rate among muscles in both right and left rotation (P < .01). The trapezius muscles have the lowest deformation rate in right rotation (P < .01). In left rotation, the trapezius and multifidus muscles showed lower deformation rates compared with most of the other muscles (P < .03). Almost all muscles were correlated in both deformation and deformation rate., Conclusion: The quadruped standing loaded dynamic neck exercise seemed to activate all the investigated neck muscles, with a tendency for more activation of the semispinalis capitis., (Copyright © 2020. Published by Elsevier Inc.)

In contemporary societies, computer use by children is a necessity and thus highly prevalent. Using computers for long hours is related to a higher risk of computer-related muscular disorders like forward head posture (FHP) and neck pain (NP). Deep cervical flexor (DCF) muscles are important head-on-neck posture stabilizers; thus, their training may lead to an improvement in FHP and NP. The aim of this study was to determine if 4 weeks of DCF training is effective in alleviating NP, improving FHP, and functional status in adolescent children using computers regularly, a pretest-posttest experimental group design was used. Subjects were randomly assigned into the experimental group (receiving DCF training and postural education) and the control group (receiving postural education only). 30 subjects with a mean age of 15.7 ± 1.725 years with NP and FHP using computers regularly participated in the study. Dependent variables were measured on day 1 (at baseline) and after 4 weeks of training. Photographic analysis was used for measuring FHP, visual analog scale for NP intensity, and neck disability index for functional status. Data analysis showed that in both groups, no significant improvement occurred in FHP. In both groups, there was a significant improvement in functional status and NP. There was no significant difference between both groups for FHP and NP. There was a significant improvement in functional status in the experimental group in comparison to the control group. Four weeks of DCF training does not cause a significant improvement in FHP in 13 to 18 years old adolescent children using computers regularly., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this paper., (Copyright © 2020 Isha Sikka et al.)

Background: The rationale of only fixation without any kind of bone, ligament, disc, or osteophyte decompression as a treatment for single- or multiple-level cervical spinal degeneration was analyzed. The concept was based on the understanding that muscle weakness-related spinal instability is the cause of spinal degeneration, and spinal stabilization is the treatment., Materials and Methods: During the period June 2012 to June 2019, 215 patients with single- or multiple-level cervical spinal degeneration who presented with symptoms of radiculopathy and/or myelopathy were treated. Age range of patients was 35-76 years. The series included 194 men and 21 women. Patients with acute symptoms and disc herniation, prolapse, or extrusion were excluded from the analysis. Only spinal stabilization by deploying facet screw fixation techniques was done in all cases. No decompression by resection of any bone, soft tissue, disc, or osteophyte was done. The minimum follow-up was 6 months., Results: Postoperative clinical outcome was measured using Japanese Orthopaedic Association score, Goel clinical grade, and visual analog scale score. In addition, 2 specialist neurosurgeons were recruited to assess clinical outcome. Clinical assessments and videos were used to document the outcome. There were no significant complications. Varying degree of clinical recovery was seen in all patients. None of the patients in the series underwent reoperation for persistence or recurrence of symptoms., Conclusions: Instability of spinal segments forms the basis of spinal degeneration. Stabilization forms the basis of surgical treatment. The role of decompression needs to be re-evaluated., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Objective: Patients with neck pain commonly have altered activity of the neck muscles. The craniocervical flexion test (CCFT) is used to assess the function of the deep neck flexor muscles in patients with musculoskeletal neck disorders. Systematic reviews summarizing the measurement properties of the CCFT are outdated. The objective of this study was to systematically review the measurement properties of the CCFT for assessing the deep neck flexor muscles., Methods: The data sources MEDLINE, EMBASE, Physiotherapy Evidence Database, Cochrane Central Register of Controlled Trials, Scopus, and Science Direct were searched in April 2019. Studies of any design that reported at least 1 measurement property of the CCFT for assessing the deep neck flexor muscles were selected. Two reviewers independently extracted data and rated the risk of bias of individual studies using the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) risk-of-bias checklist. The overall rating for each measurement property was classified as "positive," "indeterminate," or "negative." The overall rating was accompanied with a level of evidence., Results: Fourteen studies were included in the data synthesis. The ratings were positive, and the level of evidence was moderate for interrater and intrarater reliability and convergent validity. There was conflicting rating and level of evidence for discriminative validity. Measurement error was indeterminate, with an unknown level of evidence. Responsiveness was negative, with a limited level of evidence. A limitation of this study was that only papers published in English were included., Conclusions: The CCFT is a valid and reliable test that can be used in clinical practice as an assessment test. Because of the conflicting and low-quality evidence, caution is advised when using the CCFT as a discriminative test and as an outcome measure. Future better-designed studies are warranted., (© The Author(s) 2020. Published by Oxford University Press on behalf of American Physical Therapy Association. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Tremor is an important phenotypic feature of dystonia. Using the new concept (Col-Cap) of classification we examined the frequency of tremor in cervical dystonia (CD) patients, their main subtypes and muscles injected., Methods: In this large study conducted at multiple movement disorder centres in Europe and India, between January and June 2019, we examined 293 patients with idiopathic CD who were all treated with botulinum toxin (BTX)., Results: The dystonic head tremor (DHT+) was present in 57.6 % of CD patients and they had a significantly longer duration of symptoms than patients without head tremor (DHT-). In DHT+ patients torticaput was the most common subtype and the majority (63.3%) had one or two subtypes only. There was no significant difference between the number of unilateral injections for any of the muscles in the DHT+ and DHT- groups, while the number of patients receiving bilateral injections in splenius capitis (78 vs 25; p = 0.00001), sternocleidomastoid (31 vs 6; p = 0.0005), trapezius (28 vs 9; p = 0.01), and obliquus capitis inferior (15 vs 2; p = 0.008) were significantly more in the DHT+ group. The mean doses of all three types of BTX/A were not significantly different between the two groups., Conclusions: The frequency of head tremor was 57.6% in our CD patients and torticaput was the most common dystonic subtype associated with tremor. Simple forms of CD seemed more likely associated with head tremor, than complex forms of CD. Most of the DHT+ patients received bilateral injections. The use of 'Col-Cap' classification was helpful in the identification of muscles likely to be involved in tremor in CD patients., Competing Interests: Dr. Sanjay Pandey and Dr. Christian Altmann have no conflict of interest. All other authors were speakers and consultants for Allergan, Merz/Desitin and Ipsen, but none relevant to this study (and had no financial or other support)., (Copyright: © 2020 The Author(s).)

Background: Adenosine triphosphate (ATP) and glutamate are associated with some headache conditions, and purinergic (P2X) and glutamatergic N-methyl-D-aspartate (NMDA) receptor-related processes in the medulla can modulate the effects of trigeminal nociceptive afferent inputs into the brainstem on craniofacial sensorimotor circuits. This study aimed to test whether neck muscle activity can be induced in rats by noxious stimulation of the frontal dura or superior sagittal sinus that involves P2X or NMDA receptor-dependent mechanisms., Methods: While electromyographic activities of neck and craniofacial muscles were being recorded in anesthetized rats (n = 46), the inflammatory irritant mustard oil (0.2 µL, 20% MO) or vehicle (mineral oil) was topically applied to the dura or sinus, preceded by 10 µL of the ATP antagonist 2',3'-O-(2,4,6- trinitrophenyl) adenosine 5'-triphosphate (TNP-ATP, 0.1 mmol/L; n = 8) or 2-amino-5-phosphonopentanoic acid (APV, 0.05 mmol/L; n = 7) or phosphate-buffered saline (PBS as vehicle control; n = 10)., Results: Application of MO but not vehicle to the frontal dura significantly increased (P < .05) neck electromyographic activity whereas MO application to the superior sagittal sinus did not significantly increase neck electromyographic activity unless MO had previously been applied to the dura. Pre-treatment (i.t.) with TNP-ATP or APV but not vehicle control significantly reduced neck electromyographic activity evoked by MO application to the dura., Conclusions: These data suggest that noxious stimulation of the frontal dura (but not superior sagittal sinus) may enhance neck muscle activity that is P2X and NMDA receptor-dependent. These effects may contribute to neck muscle stiffness that occurs in some headache conditions., (© 2020 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: In this cross-sectional descriptive-analytical study, we sought to compare the ultrasonic thickness of the masseter muscle in people with severe forward head posture vs people without forward head posture, and to determine sex differences in muscle thickness., Methods: Thirty-eight volunteers (19 with normal head postures and 19 with severe forward head postures), aged 18 to 35 years, entered the study. The severity of the forward head posture was measured by a plumb line and the craniovertebral angle drawn on the recorded images. Based on the recorded images, the masseter muscle thickness was also measured by a 7.5-MHz linear transducer using an ultrasound device in the seated position with 3 mouth positions (closed, half open, and fully open)., Results: The results showed that the head posture affects masseter thickness significantly (P = .01), with masseter thickness significantly lower in the participants without severe forward head postures compared to those with severe forward head postures in the closed, half-open, and fully open mouth positions (P < .05). Comparing the mean masseter thickness across sexes showed that the masseter muscle is significantly thicker in men compared to women (P = .01)., Conclusion: Head posture and thickness of the masseter muscle are linked, as the masseter muscle was thicker in all 3 positions in the participants with severe forward head postures., (Copyright © 2020. Published by Elsevier Inc.)

Objective: Neck muscle dysfunction has been considered as risk factor or consequence of voice disorders. This study investigates the correlation between neck and voice-related subjective symptoms in patients with voice disorders., Study Design: Retrospective case-control study., Methods: 100 adult patients (59 female and 41 male) over 18 years with a mean age of 50.01 years (SD 16, range 24-87), of which 68 were under 60 years, were included. 50 patients had organic voice pathologies and 50 functional dysphonia. Outcome measures were the Voice Handicap Index 9 international (VHI-9i) and the Neck Disability Index (NDI-G). Spearman rank order coefficient was applied to determine the correlation between overall and single item VHI and NDI results. Subanalyses were done for functional vs. organic disorder, gender and age ± 60 years., Results: Mean overall VHI-9i (13.93, SD = 7.81, range = 0-31) and mean NDI-G (6.07, SD = 7.71, range = 0-43) showed a significant mild correlation (r s  = 0.220, P = 0.02). Split into subgroups the relation was stronger in patients with organic pathologies (r s  = 0.297, P = 0.03), but not significant in functional disorders (r = 0.148, P = 0.30). There was a moderate relation in men (r s  = 0.317, P = 0.04). Single item correlation was highest between VHI-9i item P4 (physiological) and NDI-G item reading (cognitive functioning) (r s  = 0.480, P = 0.002)., Conclusion: Specifically patients with organic voice disorders showed increased voice symptoms with the presence of neck dysfunction. This indicates a risk for a functional imbalance of the muscles surrounding the larynx, which in extreme cases may hinder functional voice rehabilitation even after phonosurgery. Therefore, neck dysfunction should be considered in voice diagnostics., (Copyright © 2018 The Voice Foundation. Published by Elsevier Inc. All rights reserved.)

Background: Neck pain is reported in more than 50% of migraine patients during migraine attacks and may be an important source to migraine pain., Objectives: To investigate phenotypical differences between migraine patients with and without ictal neck pain in the interictal phase. Additionally, to prospectively examine the association between pericranial muscle tenderness and the impending migraine attack., Methods: Migraine patients (n = 100) and controls (n = 46) underwent a semi-structured interview and sensory testing interictally. Pericranial muscle tenderness was determined using total tenderness score and local tenderness score. The occurrence of migraine attacks was then prospectively recorded for the following seven days., Results: Patients with ictal neck pain had increased tenderness of pericranial neck muscles compared to migraine patients without ( p  = 0.023). Ictal neck pain was not associated with migraine localization, tension-type headache, or markers of central sensitization. Prospective data of 84 patients showed that tenderness of trigeminal sensory innervated muscles increased the migraine attack rate ( p  = 0.035)., Conclusion: The distinction of migraine patients based on the occurrence of ictal neck pain could indicate migraine subtypes and possible involvement of peripheral tissue in the pathophysiology. Whether treatment responses differ among these groups would be fascinating. Additionally, we found that cephalic muscle tenderness is a risk factor for an impending migraine attack.

Migraine is a burdensome disease with an especially high prevalence in women between the age of 15 and 49 years. Non-pharmacological, non-invasive therapeutic methods to control symptoms are increasingly in demand to complement a multimodal intervention approach in migraine. Thirty-seven subjects (age: 25.0 ± 4.1 years; 36 females) diagnosed with high-frequency episodic migraine who presented at least one active myofascial trigger point (mTrP) in the trapezius muscles and at least one latent mTrP in the deltoid muscles bilaterally prospectively underwent six sessions of repetitive peripheral magnetic stimulation (rPMS) over two weeks. Patients were randomly assigned to receive rPMS applied to the mTrPs of the trapezius (n = 19) or deltoid muscles (n = 18). Whereas the trapezius muscle is supposed to be part of the trigemino-cervical complex (TCC) and, thus, involved in the pathophysiology of migraine, the deltoid muscle was not expected to interfere with the TCC and was therefore chosen as a control stimulation site. The headache calendar of the German Migraine and Headache Society (DMKG) as well as the Migraine Disability Assessment (MIDAS) questionnaire were used to evaluate stimulation-related effects. Frequency of headache days decreased significantly in both the trapezius and the deltoid group after six sessions of rPMS (trapezius group: p = 0.005; deltoid group: p = 0.003). The MIDAS score decreased significantly from 29 to 13 points (p = 0.0004) in the trapezius and from 31 to 15 points (p = 0.002) in the deltoid group. Thus, rPMS applied to mTrPs of neck and shoulder muscles offers a promising approach to alleviate headache frequency and symptom burden. Future clinical trials are needed to examine more profoundly these effects, preferably using a sham-controlled setting.

Unilateral agenesis of the sternocleidomastoid (SCM) muscle is a rare phenomenon known to cause torticollis. There have been around 12 reported instances of SCM agenesis in the literature; in almost every case, torticollis was easily resolved nonsurgically with stretching and physical therapy. We report the case of a 6-year-old boy with severe torticollis due to unilateral SCM absence who underwent the surgical release of the contralateral SCM. To our knowledge, this is the first time a surgical release of the SCM was performed to correct torticollis associated with agenesis of the SCM.

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: Upper crossed syndrome (UCS) refers to specific altered muscle activation and changed movement patterns along with some postural deviations in the upper quarter of the body. This syndrome might contribute to the dysfunction of the cervicothoracic and glenohumeral joints., Objectives: The present study will aim to investigate the effectiveness of a comprehensive corrective exercises program (CCEP) and subsequent detraining on alignment, muscle activation and movement pattern in men with UCS., Methods/design: This is a parallel-group randomized controlled trial. Participants will be 22 men aged 18 to 28 years who are suffering from UCS. Participants in the intervention group will conduct CCEP (three times a week for 8 weeks), followed by 4 weeks of detraining. The control group will do their daily activities. Participants will be randomized (1:1) into the intervention or the control group. The primary outcome will be upper trapezius activations. Secondary outcomes consist of electromyography of middle and lower trapezius and serratus anterior muscles, scapular dyskinesis test, forward head and shoulder angles, thoracic kyphosis angle, and neck flexion pattern test., Discussion: We propose to evaluate the effectiveness of a randomized controlled trial of a CCEP in men with UCS on their alignment, selected muscle activations, and relevant movement patterns. Results from our trial may provide new insights into the effects of exercise not only on the alignment but also on muscle activation and movement patterns that are important outcomes for people with postural malalignments and, if successful, could assist therapists in evidence-based clinical decision-making., Trial Registration: Iranian Registry of Clinical Trials, IRCT20181004041232N1. Registered on 26 October 2018.

Objective: To describe the clinical, serologic and histologic features of a cohort of patients with brachio-cervical inflammatory myopathy (BCIM) associated with systemic sclerosis (SSc) and unravel disease-specific pathophysiologic mechanisms occurring in these patients., Methods: We reviewed clinical, immunologic, muscle MRI, nailfold videocapillaroscopy, muscle biopsy, and response to treatment data from 8 patients with BCIM-SSc. We compared cytokine profiles between patients with BCIM-SSc and SSc without muscle involvement and controls. We analyzed the effect of the deregulated cytokines in vitro (fibroblasts, endothelial cells, and muscle cells) and in vivo., Results: All patients with BCIM-SSc presented with muscle weakness involving cervical and proximal muscles of the upper limbs plus Raynaud syndrome, telangiectasia and/or sclerodactilia, hypotonia of the esophagus, and interstitial lung disease. Immunosuppressive treatment stopped the progression of the disease. Muscle biopsy showed pathologic changes including the presence of necrotic fibers, fibrosis, and reduced capillary number and size. Cytokines involved in inflammation, angiogenesis, and fibrosis were deregulated. Thrombospondin-1 (TSP-1), which participates in all these 3 processes, was upregulated in patients with BCIM-SSc. In vitro, TSP-1 and serum of patients with BCIM-SSc promoted proliferation and upregulation of collagen, fibronectin, and transforming growth factor beta in fibroblasts. TSP-1 disrupted vascular network, decreased muscle differentiation, and promoted hypotrophic myotubes. In vivo, TSP-1 increased fibrotic tissue and profibrotic macrophage infiltration in the muscle., Conclusions: Patients with SSc may present with a clinically and pathologically distinct myopathy. A prompt and correct diagnosis has important implications for treatment. Finally, TSP-1 may participate in the pathologic changes observed in muscle., (Copyright © 2020 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.)

The pathophysiology of dropped head syndrome (DHS) remains unknown, and its treatment algorithm and indication are not standardized. Here, we established a novel rehabilitation program, short and intensive rehabilitation program for DHS (SHAiR program), consisting of cervical paraspinal muscles exercise, range of motion exercise, cervical and thoracic mobilization, deep cervical flexor muscle exercise, hip lift exercise, anterior pelvic tilt exercise, and walking exercise. The aim of this study was to evaluate the clinical effectiveness of this program. We reviewed clinical outcomes for five consecutive patients with DHS who underwent the SHAiR program (SHAiR group). The outcomes were compared with those of other five patients with DHS who received exercise instruction (control group). Demographic data, the duration from onset of DHS, the apex of sagittal kyphosis on the lateral radiographs, and clinical outcomes including the ability to maintain normal horizontal gaze, chin brow vertical angle, and numerical rating scale (NRS) were evaluated at the initial visit and final follow-up at 7.5 months. There was no significant difference between the two groups in terms of demographic and radiographic data. The ability of horizontal gaze and NRS of cervical pain improved rapidly for all five patients in the SHAiR group as compared to no improvement for all patients in the control group. Rehabilitation for DHS was considered effective not only for localized rehabilitation such as exercise for training cervical extensor muscle function but also exercises for thoracolumbar posture improvement and the psoas muscle., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Rationale: In patients with chronic obstructive pulmonary disease (COPD), increased activity of neck inspiratory muscles has been reported as a compensatory response to hyperinflation-related diaphragmatic dysfunction. The persistence of this activity during sleep could attenuate sleep-related hypoventilation and also negatively impact sleep and clinical outcomes. Objectives: To assess the persistence of neck-muscle activity during sleep in patients with COPD recovering from severe exacerbations (i.e., requiring hospitalization) and its impact on sleep quality and recurrence of exacerbations. Methods: Video polysomnography with neck-muscle EMG was performed in patients with COPD who were recovering from a severe exacerbation. The follow-up period lasted 6 months to record the next severe exacerbation. Measurements and Main Results: Twenty-nine patients were included in the study (median [25th-75th percentile] age, 71 [64-72] yr; 55% male; body mass index, 24 [21-29]; FEV 1 % predicted, 37 [29-45]; and BODE [body mass index, airflow obstruction, dyspnea, and exercise] index, 6 [5-7]). Twenty-six of these patients exhibited sleep-related neck-muscle activity, which was intermittent (limited to stage 3 sleep) in 17 and permanent throughout sleep in 9. α-Delta EEG activity during stage 3 sleep was observed in 87% of the patients. Compared with patients with no or intermittent neck-muscle activity, those with permanent neck-muscle activity showed more disrupted sleep, had experienced more exacerbations in the previous year, and suffered their next severe exacerbation earlier. Conclusions: Sleep-related neck-muscle activity occurs frequently in patients with COPD who are recovering from a severe exacerbation and seems to negatively affect sleep quality and prognosis; therefore, identification of this activity might improve COPD management after a severe exacerbation.

Head injuries frequently occur in American football and other contact sports. Uncertainty on the effects of cervical muscle properties on head injury risk may be due to the limitations of previous observational studies. This simulation study employs a musculoskeletal model of the head and neck to investigate the effect of several factors related to head injury metrics in American Football. These factors include isometric muscle strength, the eccentric multiplier (which is related to the athlete's ability to apply greater muscle force during eccentric contractions), posture, muscle activation patterns, and impact properties. Impact properties were based on the literature and tuned to reproduce peak linear and rotational accelerations of the skull. We hypothesized that active neck muscles significantly reduce head injury metrics. We systematically altered each model parameter to test our hypothesis. We then determined which model parameters affect head injury metrics the most. The results of this study indicate that active neck muscles have a statistically significant effect on head injury metrics. Increasing muscle strength and eccentric multiplier also resulted in a statistically significant reduction of head injury metrics. However, posture prior to impact had a much stronger effect than any other factor on head injury metrics. A comprehensive approach to athlete training protocols is recommended, including exercises aimed at increasing eccentric muscle strength and preparation for impacts. Future studies should investigate how targeted muscle strengthening and impact training (i.e. activation patterns and posture) modifies risk., Competing Interests: Conflict of Interest Statement The authors declare no conflicts of interest., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: Guillain-Barré syndrome (GBS), when severe, involves the autonomic nervous system; our objective was to assess the spectrum and predictors of dysautonomia, and how it may impact functional outcomes., Methods: A retrospective review of patients admitted to the Mayo Clinic in Rochester, MN between January 1, 2000, and December 31, 2017, with GBS and dysautonomia was performed. Demographics, comorbidities, parameters of dysautonomia, clinical course, GBS disability score, and Erasmus GBS Outcome Score (EGOS) at discharge were recorded., Results: One hundred eighty seven patients were included with 71 (38%) noted to have at least one manifestation of dysautonomia. There are 72% of patients with a demyelinating form of GBS and 36% of patients with demyelination had dysautonomia. Ileus (42%), hypertension (39%), hypotension (37%), fever (29%), tachycardia or bradycardia (27%), and urinary retention (24%) were the most common features. Quadriparesis, bulbar and neck flexor weakness, and mechanical ventilation were associated with autonomic dysfunction. Patients with dysautonomia more commonly had cardiogenic complications, syndrome of inappropriate antidiuretic hormone, posterior reversible encephalopathy syndrome, and higher GBS disability score and EGOS. Mortality was 6% in patients with dysautonomia versus 2% in the entire cohort (P = 0.02)., Conclusions: Dysautonomia in GBS is a manifestation of more severe involvement of the peripheral nervous system. Accordingly, mortality and functional outcomes are worse. There is a need to investigate if more aggressive treatment is warranted in this category of GBS.

Dropped head syndrome can be the presenting feature of a wide spectrum of neurological conditions. In this study, we aimed to define the clinical characteristics and treatment outcomes of 107 patients, where head drop was the presenting or predominant clinical feature of a myopathy. Median age at presentation was 68 years (range 42-88). A specific diagnosis was reached in 53% of patients: Inflammatory myopathy (n = 16), myopathy with rimmed vacuoles (n = 10), radiation-induced myopathy (n = 8), sporadic late-onset nemaline myopathy (n = 7), myofibrillar myopathy (n = 4), facioscapulohumeral dystrophy (n = 3), inclusion body myositis (n = 2), mitochondrial myopathy (n = 2), scleroderma-associated myopathy (n = 2), and single cases of necrotizing autoimmune myopathy, drug-induced myopathy, and B-cell chronic lymphocytic leukemia-myopathy. Splenius capitis had the highest diagnostic yield for a muscle biopsy (67%). When tested, 31/35 (89%) of patients had abnormal pulmonary function tests, 15/30 (50%) abnormal swallow evaluation, 24/65 (37%) abnormal electrocardiogram and 5/38 (13%) abnormal transthoracic echocardiogram. 23/43 (53%) treated patients responded to treatment. Patient-reported limb weakness and neck flexion weakness on physical examination were associated with good response to treatment. A wide spectrum of acquired and hereditary myopathies can present with head drop, some of which are potentially treatable. Establishing a diagnosis is crucial for timely treatment administration, screening for swallowing and cardiorespiratory involvement, and counseling regarding prognosis., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: Individuals with neck pain have different movement and muscular activation (collectively termed as biomechanical variables) patterns compared to healthy individuals. Incorporating biomechanical variables as covariates into prognostic models is challenging due to the high dimensionality of the data., Research Question: What is the classification performance of neck pain status of a statistical model which uses both scalar and functional biomechanical covariates?, Methods: Motion capture with electromyography assessment on the sternocleidomastoid, splenius cervicis, erector spinae, was performed on 21 healthy and 26 individuals with neck pain during walking over three gait conditions (rectilinear, curvilinear clockwise (CW) and counterclockwise (CCW)). After removing highly collinear variables, 94 covariates across the three conditions were used to classify neck pain status using functional data boosting (FDboost)., Results: Two functional covariates trunk lateral flexion angle during CCW gait, and trunk flexion angle during CW gait; and a scalar covariate, hip jerk index during CCW gait were selected. The model achieved an estimated AUC of 80.8 %. For hip jerk index, an increase in hip jerk index by one unit increased the log odds of being in the neck pain group by 0.37. A 1° increase in trunk lateral flexion angle throughout gait alone reduced the probability of being in the neck pain group from 0.5 to 0.15. A 1° increase in trunk flexion angle throughout gait alone increased the probability of being in the neck pain group from 0.5 to 0.9., Significance: Interpreting the physiological significance of the extracted covariates, with other biomechanical variables, suggests that individuals with neck pain performed curvilinear walking using a stiffer strategy, compared to controls; and this increased the risk of being in the neck pain group. FDboost can produce clinically interpretable models with complex high dimensional data and could be used in future prognostic modelling studies in neck pain research., Competing Interests: Declaration of Competing Interest All authors declare that they have no conflicts of interest., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Competing Interests: Funding: None. Conflicts of Interest: The authors report no conflicts of interest. Ethics Statement: All patients who appear on the video have provided written informed consent and authorization for videotaping and publication of the videotape.

The objective of this investigation was to evaluate the activity of the suprahyoid musculature during swallowing and to correlate the findings with the degree of megaesophagus, oral and pharyngeal videofluoroscopy and esophageal manometry in patients with achalasia caused by Chagas' disease. Twenty-nine patients with positive serology for Trypanosoma cruzi and dysphagia (Chagas' disease group) and 29 individuals matched by sex and age (control group) participated in the study. Surface electromyography of the suprahyoid musculature and videofluoroscopy during swallowing of paste and liquid consistencies were performed. Canonical correlation analysis of the MANOVA test results showed that the Chagas' disease group had lower electromyographic activity when compared with controls. Overlapping circles of radiological findings were found for megaesophagus. The Spearman test showed a positive correlation between the electromyographic activity in the maximum voluntary isometric contraction and the time of pharyngeal transit for both liquid (p = 0.014) and paste (p = 0.047). The logistic regression test showed no association between electromyographic activity of the suprahyoid muscles and esophageal manometry results (p > 0.05). In conclusion, individuals with chagasic megaesophagus have reduced electromyographic activity of the suprahyoid muscles during swallowing, in addition to a greater recruitment of the suprahyoid musculature with increased pharyngeal transit time.

This study examined the differences in neck muscle activity at various neck flexion angles in smartphone users with and without neck pain. Forty-four participants performed texting tasks for 1 min and 30 s. Neck muscle activity and pain in the neck were measured at different neck flexion angles. There was a difference in neck muscle activity for each of the neck flexion angles; the Cervical Erector Spinae (CES) muscle activity increased while the Upper Trapezius (UT) muscle activity decreased when at increased neck flexion angles. At neck flexion angle of 0°-15°, the activity of both CES and UT muscles were acceptably low. Smartphone users with neck pain had slightly higher muscle activity levels than smartphone users without neck pain. In conclusion, smartphone users should consider adopting neck flexion angles between 0 and 15 degrees during smartphone use as there is an association between this neck flexion angle range and reduced CES muscle activity. Practitioner summary: This study demonstrated that both smartphone users with and without neck pain should try to keep their neck flexion angle between 0° and 15° when using their smartphone. This would reduce neck muscle activity and the risk of developing neck disorders associated with smartphone use.

Motor development in infants is dependent upon the function of the inner ear balance organ (vestibular organ). Vestibular failure causes motor delays in early infancy and suboptimal motor skills later on. A vestibular test for newborns and infants that is applicable on a large scale, safe and cost effective is in demand in various contexts: in the differential diagnosis of early onset hearing loss to determine forms associated with vestibular failure; in early hearing habilitation with cochlear implant, indicating the vestibular predominant side; and in the habilitation of children affected by motor skill disorders, revealing the contribution of a vestibular failure. This work explored the feasibility of cervical vestibular evoked myogenic potentials (VEMP) in conjunction with newborn universal hearing screening program. VEMP was measured after the hearing tests and was evoked by bone-conducted stimuli. Moreover, stimulus delivery was regulated by neck muscle activity, with infants rested unconstrained in their parents´ arms and with the head supported by the operator´s hand. This VEMP protocol showed a high level of feasibility in terms of test viability and result reproducibility. VEMP integrated into the newborn hearing screening program may represent a practical method for large-scale assessment of balance function in infants.

Background: Altered thickness, cross-sectional area and activity of deep neck muscles have frequently been reported in patients with chronic non-specific neck pain (CNNP). It is claimed that these muscles do not recover spontaneously. These muscles provide a considerable amount of cervical stability. Therefore, various therapeutic exercises have been recommended to recover from resulting complications. However, most exercise protocols do not target deep neck muscles directly. Thus, this might be a reason for long-lasting complications. Accordingly, the purpose of the present study is to discuss a randomized controlled trial (RCT) protocol in which we aim to investigate and compare the effects of neck-specific exercise programmes versus general exercise programmes in patients with CNNP., Methods: A 2*2 factorial RCT with before-after design. Sixty-four participants with CNNP will be recruited into the study. They will be randomly divided into two groups, including specific neck exercise and general exercise. Each exercise programme will be carried out three times a week and will last for 8 weeks. Primarily, dorsal and ventral neck muscle thickness, pain and disability and secondarily, muscle strength, quality of life, sleep quality, fear avoidance and neck range of motion will be assessed at the baseline and immediately at the end of the exercise protocol., Discussion: The results of this study will inform clinicians on which type of exercise is more beneficial for patients with CNNP., Trial Registration: IRCT2017091620787N2, Sep 16 2017.

Background: Dropped head syndrome (DHS) is a low prevalence and the clinical features remain unclear. The purpose of the present study was to clarify the general overview of DHS., Methods: The subjects were 67 consecutive DHS patients (17 men and 50 women; average age 72.9 ± 10.2 years) presenting difficulty of horizontal gaze in up-right position. The patients' background, global spinal alignment, clinical findings and treatment were analyzed., Results: The peak population of DHS was 75-79-year-old females. The comorbidities included Parkinson's disease in 9 cases, minor trauma in 9 cases, post-cervical operation in 3 cases, mental depression in 3 cases, malignant tumor in 3 cases, diabetes mellitus in 2 cases and rheumatoid arthritis in 2 cases. The C2-C7 cervical coronal vertical axis was distributed more to the right side (2.6 ± 12.8 mm). Regarding sagittal alignment, 24 cases (35.8%) showed negative balanced DHS (N-DHS) and 43 cases (64.2%) showed positive balanced DHS (P-DHS). There were significant differences in C2-C7 angle, T1S, LL and PI-LL between the two groups. Cervical or back pain was present in 62 cases (92.5%), and average numerical rating scale was 3.0 ± 2.6. Fourteen cases (20.9%) recovered (average 11.3 months), but 29 cases (43.3%) did not recover without surgery. Twenty-four cases (35.8%) underwent surgery, 20 for cervical spine and 4 for thoraco-lumbar spine, and horizontal gaze difficulty was improved in all patients post-surgery., Conclusion: DHS was mainly observed in elderly women. About 20% of DHS patients recovered without surgical treatment. DHS was accompanied by scoliosis in 37.3% of the cases., (Copyright © 2019. Published by Elsevier B.V.)

Objective: To investigate the association between the presence of self-reported neck pain in patients with migraine and clinical features, upper cervical mobility, and neck muscle performance., Methods: A total of 142 patients with migraine were recruited and stratified by the presence (n = 99) or absence of self-reported neck pain (n = 43). The clinical examination included the Migraine Disability Assessment, the 12-item Allodynia Symptom Checklist, a flexion rotation test, and the Craniocervical Flexion Test., Results: Migraine-related disability was reported by more than 80% in both groups ( p  = 0.82). However, there was a greater prevalence and severity of cutaneous allodynia observed in the group with neck pain ( p  < 0.001). Reduced upper cervical mobility was verified in 67% of the patients with neck pain and in 41% of those without neck pain ( p  = 0.005). In addition, 67% of the patients with neck pain and 40% without neck pain were not able to maintain the third stage of the Craniocervical Flexion Test without compensation ( p  = 0.003)., Conclusions: The presence of self-reported neck pain in patients with migraine was associated with a poor clinical presentation regarding cutaneous allodynia, neck mobility, and muscle function. However, there were no differences in migraine-related disability.

Purpose: Neck pain is considered a common characteristic of migraine attacks. The relationship between neck pain and migraine can be explained by central sensitization of the trigeminocervical complex, where superior cervical afferents and the trigeminal nerve converge. However, few studies have evaluated motor control of cervical muscles in individuals with migraine. Thus, the purpose of the present study was to determine the extensor/flexor ratio of neck muscle strength and electromyographic activity during a test of maximal voluntary isometric contraction and craniocervical flexion in individuals with migraine and individuals without history of migraine or other headaches., Methods: Fifty-two women with the disease and 52 women with neither a history of migraine nor neck pain, between 18 and 55 years old, were included in the study. The electromyographic activities of the sternocleidomastoid, anterior scalene, splenius capitis, and upper trapezius muscles were evaluated during a test of maximal voluntary isometric contraction and craniocervical flexion., Results: The migraine group presented lower flexor muscle strength and a higher extensor/flexor muscle strength ratio than the control group. In addition, the migraine group showed a reduced electromyographic extensor/flexor muscle ratio during maximal voluntary isometric contraction in flexion. The results demonstrated worse performance in the craniocervical flexion test of the migraine group and a lower electromyographic ratio of extensor/flexor neck muscles in the last stage of the test., Conclusion: Altogether, the migraine group presented an imbalance in cervical muscles verified not only during force production, but also during muscle activity. These slides can be retrieved under Electronic Supplementary Material.

Introduction: Neck pain is a very common musculoskeletal complaint in industrialized countries. Theoretically, chronic neck pain is thought to possibly change biomechanics and muscle activation patterns of the shoulder complex, causing its pain and dysfunction in the long term., Purpose: The present cross-sectional study was conducted to compare shoulder complex muscle activation characteristics in patients with chronic non-specific neck pain, compared to healthy participants., Method: Twenty patients with chronic neck pain and twenty healthy participants were recruited for the present study. Surface Electromyographic (sEMG) activity was recorded from four selected muscles (anterior and middle deltoid, upper and lower trapezius) during shoulder elevation with a predetermined load (25-30% of an individual's maximum voluntary exertion)., Result: Results revealed only two significant increased onset delays in the anterior and middle deltoid,and a peak delay in the upper trapezius in chronic neck pain patients. Furthermore, increased onset delay for other muscles and decreased peak normalized amplitude (MVE%) for all muscles were found in chronic neck pain patients; however, these findings were not statistically significant., Conclusion: There were relationships between chronic non-specific neck pain and the shoulder muscle activation characteristic; hence, the alteration may be considered a predisposing factor for the shoulder dysfunction in future studies., (Copyright © 2019. Published by Elsevier Ltd.)

Objectives : The purpose of this study was to describe the reliability and validity of measurements of cervical retraction strength obtained with a hand held dynamometer (HHD) from healthy adults. Background : Impaired neck muscle strength is related to neck pain, abnormal posture, and various cervical pathologies. While sophisticated devices to objectively measure neck strength exist, many are not practicable in typical orthopedic practices or have questionable validity and reliability. Methods : Forty participants were included in the analysis of neck strength using isometric testing with an HHD fixed in a cradle on a table top. The highest neck retraction force recorded in Newtons (N) for each participant, was used for data analysis. Results : Both intratester and intertester reliability were excellent as judged by intraclass correlation coefficients (ICCs) (.885 - .974) and minimal detectable change (MDC) (21.1 to 47.6 N). Validity was confirmed on the basis of expected gender and age differences (ie, men were stronger than women and younger participants were stronger than older participants). Conclusion : Fixed HHD is a reliable and valid tool for measuring isometric neck retraction strength in ostensibly healthy adults. Its value in the assessment of individuals with neck pathology awaits further examination.

Background: People with whiplash-associated disorders (WADs) report difficulty with quick head movements and cervicoocular dysfunction. Changes in coordination between eye movement and neck muscle activity may be involved., Objective: To examine whether activity of superficial and deep neck muscles increases with eye movement when the head is held in a fixed position, whether this differs between directions and speed of eye movement, and whether this is modified in WAD., Design: Convenience case series with unmatched controls., Setting: Research laboratory., Participants: Nine individuals with chronic WAD grade II and 11 pain-free controls., Methods: Electromyography (EMG) was recorded from muscles that could act to rotate the neck to the right (right obliquus capitis inferior [OI], multifidus [MF], splenius capitis [SC], and left sternocleidomastoid [SCM]) with intramuscular or surface electrodes in 9 WAD participants and 11 pain-free controls. Eyes were rotated without head movement to track slow and medium-speed targets to the right or left, and as fast as possible (FP)., Main Outcome Measurements: Amplitude of EMG., Results: In controls, SCM and SC EMG increased with right gaze (all P's < .03). EMG of the deep OI muscle increased in both directions (P < .001). WAD involved counterintuitive greater activity of SCM with left rotation across speeds of eye movement (SC with slow movement, P < .036), decreased OI EMG with gaze left (P < .019), and no change in MF EMG (P < .6) in either gaze direction. For FP tasks, EMG of all muscles was greater than slower speeds in controls (all P's < .0001), but not WAD (all P's > .33)., Conclusions: Coordination between neck muscle activity and eye movements with increasing speed is modified in WAD. Contrasting changes are present in deep and superficial neck muscles with implications for neck function that may explain some common WAD symptoms., Level of Evidence: IV., (© 2019 American Academy of Physical Medicine and Rehabilitation.)

Background: Dropped head syndrome is a potential late neurologic complication of radiation therapy in survivors of Hodgkin lymphoma. There is limited evidence for conservative management of this condition., Objective: To discover patient utilization patterns of the commonly prescribed Headmaster Collar (cervical) in Hodgkin lymphoma survivors with radiation-induced dropped head syndrome., Design: Questionnaire-based retrospective observational study., Setting: Single-site academic cancer center., Patients: Twenty-six Hodgkin lymphoma survivors treated with radiation therapy involving the mantle who were prescribed a Headmaster Collar for dropped head syndrome., Methods or Interventions: Patients were interviewed by phone with a structured set of questions., Main Outcome Measurements: Compliance, patterns of use, individual modifications, and side effects of collar use., Results: Although 58% of patients who were prescribed a Headmaster Collar eventually discontinued its use, 62% of all patients used the collar for more than 6 months. The majority of users wore the collar for up to 3 hours per day, usually for static seated activities. Thirty-eight percent of patients made personal modifications to their collar, most commonly the addition of extra padding. All but one patient had complaints about the collar, most commonly discomfort, rigidity, and confinement., Conclusions: The Headmaster Collar (cervical) is often utilized for a few hours a day, for longer than 6 months, to help with static seated activities. Insights from this study might help to improve future orthotic designs with better long-term compliance rates for the treatment of radiation-induced dropped head syndrome., Level of Evidence: IV., (© 2018 American Academy of Physical Medicine and Rehabilitation.)

Objective: This paper presents the first study where a dynamic neck brace was used to characterize the head motion of ALS patients while concurrently recording the surface electromyography (EMG) of the neck muscles., Methods: Eleven ALS patients and 10 age-matched healthy controls consented and participated in an experiment. Each participant was asked to perform three single-plane motions of the head-neck that included flexion-extension in the sagittal plane, lateral bending in the coronal plane, and axial rotation in the transverse plane. Each motion was performed in a cycle and was repeated five times at self-selected speeds., Results: During single-plane flexion-extension under gravity, compared to healthy peers, ALS patients showed a shorter duration to reach the maximum flexion and an earlier EMG onset in the neck extensors starting from the neutral. The brace measures in activation of the neck muscles in ALS patients were well correlated with clinically measured scores, such as the ALSFRS-r and the FVC. The activation duration of sternocleidomastoid, used to rotate the head, correlated well with the ALSFRS-r and FVC in ALS patients during axial rotation., Interpretation: The ability to synchronously activate a pair of muscles to execute single-plane motions in ALS patients seems to have been compromised due to the disease and potentially results in head drop. The neck brace measures can be adapted in the clinic to complement self-reporting in ALS patients and used to assess the head drop and progress of the disease., (© 2019 The Authors. Annals of Clinical and Translational Neurology published by Wiley Periodicals, Inc. on behalf of American Neurological Association.)

Objectives : Headaches can be associated with rhinosinusitis and may present a diagnostic challenge because of symptomatic overlap with other recurring headaches. Neck pain has received extensive attention in migraine, tension-type and cervicogenic headache but not as a comorbid feature of headache in those with rhinosinusitis. This study investigated the occurrence of neck pain and cervical musculoskeletal dysfunction in individuals with self-reported sinus headaches (SRSH). Methods : Participants with and without SRSH attended a single data collection session. Participants completed the Headache Impact Test (HIT)-6 and the Sino-Nasal Outcome Test (SNOT)-22. Cervical range of motion (ROM), segmental examination, muscle endurance and pressure-pain threshold (PPT) were measured . Results : Participants included 31 with SRSH (77.4% female; age 43.7 (9.9) years) and 30 without headache. Average symptom duration was 89.7 (±85.6) months. Mean SNOT-22 and HIT-6 scores were 36.2 (15.3) and 56.7 (7.1), respectively. In the SRSH group, 83.9% ( n = 26) reported neck pain. There was a significant difference between groups for cervical sagittal (14.3° [5.3°, 23.3°], p = 0.002) and transverse plane ROM (21.5° [12.4°, 30.6°], p < 0.001), but no difference in frontal plane motion ( p = 0.017). There were significant between groups difference in neck flexor endurance (19.5 s [10.1 s, 28.9 s], <0.001), segmental dysfunction O-C4 ( p < 0.001) but not in PPT ( p = 0.04). Discussion : Neck pain and cervical musculoskeletal dysfunction are common among persons with SRSH and may be a comorbid feature or contributing factor to headaches attributed to rhinosinusitis. Further research is needed to understand these associations.

The distribution of muscle weakness in myasthenia gravis (MG) patients with acetylcholine receptor (AChR) antibodies is highly variable. As muscle groups respond differently to therapeutic interventions, it is important to acknowledge this variability. We analysed the distribution of muscle weakness in 225 AChR MG patients over time. On the basis of combinations of muscle weakness, seven phenotypes were defined: 'ocular' (O), 'bulbar' (B), 'neck/limbs/respiratory' (NLR), or a combination (O+B, O+NLR, B+NLR and O+B+NLR). MG remained restricted to ocular weakness in 5%, whereas 7% never had ocular weakness. At last follow-up, ocular or bulbar weakness had resolved more frequently than NLR weakness (40%, 38% and 25%; p = 0.003, respectively). Patients with O, B or OB phenotype at baseline had a higher age at onset and were more frequently male than patients with NLR, ONLR, BNLR or OBNLR phenotype (52.7 ± 17.5 vs. 44.0 ± 18.9; p = 0.007 and 64% vs. 37%; p = 0.002, respectively). MG patients have heterogeneous distributions of muscle weakness and frequently shift between phenotypes. The phenotypic variations found in AChR MG suggest that also other factors aside from the AChR antibody mediated immune response are of importance in determining the disease expression in MG., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

Objectives : To compare the performance of cervical stabilizer muscles using the craniocervical flexion test (CCFT) among individuals with subacute, chronic, and asymptomatic low back pain (LBP) conditions. Methods : Individuals with subacute ( N = 23) and chronic LBP ( N = 23) with their age- and gender-matched controls ( N = 30) participated in this study. All recruited participants were required to perform the CCFT. The activation score (AS) and the performance index (PI) were recorded by an assessor who was blinded to the group of participants. Results : Approximately, 74% of subacute LBP participants and 60-65% of chronic LBP participants obtained abnormal AS and PI. AS was significantly lower in participants with subacute ( P = 0.0002) and chronic LBP ( P = 0.0009) than the control group. Likewise, the PI was significantly lower in participants with subacute ( P = 0.0002) and chronic LBP ( P = 0.0036) than the control group. Participants in the subacute LBP group showed significantly greater percentages of abnormal responses on the AS ( P < 0.0001) and the PI ( P = 0.0001) than the control. Discussion : Abnormal performance of cervical stabilizer muscles using the CCFT was demonstrated in a high proportion of participants with LBP. The findings highlight the plausible association in muscle control between cervical and lumbar stabilizers. Level of Evidence : 2b.

Objectives: The present study's objective was to understand the causal mechanisms underpinning the recovery of individuals with whiplash-associated disorders (WAD). We applied Bayesian Networks (BN) to answer 2 study aims: (1) to identify the causal mechanism(s) of recovery underpinning neck-specific exercise (NSE), and (2) quantify if the cyclical pathway of the fear-avoidance model (FAM) is supported by the present data., Materials and Methods: We analyzed a prospective cohort data set of 216 individuals with chronic WAD. Fifteen variables were used to build a BN model: treatment group (NSE with or without a behavioral approach, or general physical activity), muscle endurance, range of motion, hand strength, neck proprioception, pain catastrophizing, fear, anxiety, depression, self-efficacy, perceived work ability, disability, pain intensity, sex, and follow-up time., Results: The BN model showed that neck pain reduction rate was greater after NSE compared with physical activity prescription (β=0.59 points per month [P<0.001]) only in the presence of 2 mediators: global neck muscle endurance and perceived work ability. We also found the following pathway of variables that constituted the FAM: anxiety, followed by depressive symptoms, fear, catastrophizing, self-efficacy, and consequently pain., Conclusions: We uncovered 2 mediators that explained the mechanisms of effect behind NSE, and proposed an alternative FAM pathway. The present study is the first to apply BN modelling to understand the causal mechanisms of recovery in WAD. In doing so, it is anticipated that such analytical methods could increase the precision of treatment of individuals with chronic WAD.

Purpose: Neck muscle vibration immediately improves cervical joint position sense and dynamic postural control but increases pressure pain thresholds in neck pain patients. The aim of this study was to explore longer lasting effects of neck muscle vibration on sensorimotor control and pressure pain threshold. Materials and methods: Five series of neck muscle vibration were delivered to 15 neck pain patients and 11 healthy controls in this case control study. Outcomes were cervical joint position sense, arm-matching acuity, and pressure pain threshold at the zygapophyseal joint of C2/C3, the angulus superior, and the tibialis anterior muscle. Results: Cervical joint position sense acuity improved in neck pain patients and declined in healthy controls even after 24 h. Arm-matching acuity improved in patients assessed after 15 min, as was pressure pain threshold at the angulus superior in neck pain patients. In contrast, changes in the pressure pain threshold at the tibia were only observable immediately after vibration. Conclusion: Neck muscle vibration induced short-lasting general as well as longer-lasting specific effects on analgesia and sensorimotor function. Based on our observations, future studies should investigate potential benefits of neck muscle vibration as adjunct to physical therapy in order to improve cervical sensorimotor function. Implications for Rehabilitation A single session of neck muscle vibration improves cervical joint position sense in neck patients for up to 24 h. Neck muscle vibration improves arm-matching acuity in neck pain patients. Neck muscle vibration increases pressure pain thresholds at the stimulated place but decrease pressure pain thresholds more distally. Neck muscle vibration shows distinct effects in neck pain patients and healthy control.

Aims: Neck pain is common in migraine and tension type headache (TTH). This review aimed to examine the evidence for cervical musculoskeletal impairments in these headaches., Methods: Databases PubMed (Medline), EMBASE, CINAHL, SCOPUS, and Web of Science were searched from inception to December 2018. Observational studies using a comparator group were included. Risk of bias was assessed using the Appraisal tool for Cross-Sectional Studies. Results were pooled using random effects meta-analysis. Level of evidence for each outcome was assigned based on risk of bias, consistency of results and magnitude of difference between participants with headache and controls. (PROSPERO registration: CRD42018083683)., Results: Of 48 studies included, the majority were rated moderate risk of bias due to possible confounding influences. In total, 17 cervical outcomes were assessed, with confidence in findings ranging from very low to moderate levels. Compared to controls, participants with TTH had greater forward head posture (FHP) (MD = -6.18°, 95% CI [-8.18°, -4.18°]) and less cervical range of motion (ROM) (greatest difference transverse plane MD = -15.0°, 95% CI [-27.7°, -2.3°]. Participants with migraine demonstrated minimally reduced cervical ROM (greatest difference sagittal plane MD = -5.4°, 95% CI [-9.9°, -0.9°]. No differences presented in head posture, strength, craniocervical flexion test performance or joint position error between migraineurs and controls., Conclusions: TTH presented with more findings of cervical musculoskeletal impairments than migraine however levels of confidence in findings were low. Future studies should differentiate episodic from chronic headache, identify coexisting musculoskeletal cervical disorders, and describe neck pain behaviour in headache., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: A reduced capacity to generate and sustain cervical muscle force over a range of contraction intensities is a feature of some participants with neck pain. To date there have been no studies comparing the accuracy of force perception in participants with and without neck pain., Design: Cross-sectional observational study., Methods: Participants with (n = 25) and without (n = 25) neck pain performed isometric muscle contractions at three progressive self-perceived (no feedback provided) intensities (10, 25, 50) % of their maximal voluntary contraction (MVC) in cervical: flexion, extension, right and left lateral flexion. Absolute error (AE), constant error (CE), and variable error (VE) between actual and targeted force values were calculated., Results: The neck pain group had: (1) AE-combined direction -significantly higher at 10% and lower at 50% (p < 0.05); (2) significantly lower CE in most measures (p < 0.05); (3) higher mean VE in all measures, with 10, 25, and 50% combined direction and overall combined % extension significantly higher (p < 0.05)., Conclusions: Findings indicate higher variability in force generation perception across all directions and intensities in participants with neck pain compared to healthy controls. Potentially this greater variability might suggest impaired force sense, a construct of proprioception in participants with neck pain. Reduced force sense may have implications for participants with neck pain during functional activities requiring precision and may need to be trained. Further research is required., (Copyright © 2019. Published by Elsevier Ltd.)

Background: The aim of this study was to identify factors influencing shoulder and/or neck function in patients up to five years after treatment., Materials and Methods: Lateral flexion of the neck, ipsilateral forward flexion, and abduction of the shoulder were measured. Potential factors were entered into a linear mixed model analysis to create a multivariate model for describing the results., Results: Predicted neck and shoulder function was negatively influenced by higher age before intervention. Contralateral flexion of the neck was lower for patients undergoing surgery and radiotherapy compared to surgery. Ipsilateral flexion of the neck is influenced by a higher age at baseline. Ipsilateral shoulder abduction is lower for female gender, bone graft/flap reconstruction, and more extensive neck dissection. Ipsilateral forward flexion of the shoulder is lower for bone graft/flap reconstruction and better for patients with a T2 tumor in comparison to T3 and T4 tumors, as predicted., Conclusion: By our five-year follow-up outcomes of this study, neck and/or shoulder impairments can be found for high-risk patients by physiotherapists.

Background: Chronic neck pain affects a significant percentage of the adult population. Commonly, the pain is of unknown origin. In those cases, some alterations in motor control (MC) can appear in the deep cervical muscles. The specific training of these muscles could improve muscular function and reduce pain and disability., Objective: To determine whether MC, using cranio-cervical flexion (CCF), is more effective than other treatments for non-specific chronic neck pain (NSCNP)., Design: Systematic review with meta-analysis., Methods: A search was done in journals and in a variety of databases, between December 2017 and March 2018. Randomized clinical trials (RCTs) and systematic reviews of RCTs comparing MC with other treatments in adults with NSCNP, regarding pain and disability, were included. Risk of bias was analysed using the Cochrane risk of bias tool. Data was analysed using a random effects model. Heterogeneity was evaluated using the I 2 statistic. The quality of the evidence was measured using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach., Results: Ten articles were included for qualitative review; nine were used for a quantitative analysis about the effect of MC on pain and eight for the analysis regarding disability. The meta-analysis comparing MC versus other treatments showed significant differences regarding pain and disability., Conclusions: MC interventions for NSCNP patients reduces pain and disability. MC seems to be more effective to reduce pain and disability than other treatments., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Sensorimotor control of neck muscles differs between individuals with and without pain. Differences in the primary motor cortex (M1) maps of these muscles may be involved. This study compared M1 representations of deep (DNF) and superficial (SNF) neck flexor muscles between 10 individuals with neck pain (NP) and 10 painfree controls. M1 organisation was studied using transcranial magnetic stimulation (TMS) applied to a grid over the skull and surface electromyography of DNF (pharyngeal electrode) and SNF. Three-dimensional maps of M1 representation of each muscle were generated. Peaks in the SNF map that represented the sternocleidomastoid (SCM) and platysma muscles were identified. Unique centre of gravity (CoG)/map peaks were identified for the three muscles. In comparison to painfree controls, NP participants had more medial location of the CoG/peak of DNF, SCM, and platysma, greater mediolateral variation in DNF CoG (p = 0.02), fewer SNF and DNF map peaks (p = 0.01). These data show that neck flexor muscle M1 maps relate to trunk, neck, and face areas of the motor homunculus. Differences in M1 representation in NP have some similarities and some differences with observations for other musculoskeletal pain conditions. Despite the small sample size, our data did reveal differences and is comparable to other similar studies. The results of this study should be interpreted with consideration of methodological issues., (© 2019 Wiley Periodicals, Inc.)

Objective: To determine the changes produced by trigger point dry needling (TrP-DN) of sternocleidomastoid in patients with neck pain, and to observe how it might modify cervical motor control (CMC)., Design: Single-centre, randomised, double-blinded clinical trial., Setting: Participants were recruited through advertising. The duration of the study was 6 months., Subjects: Thirty-four subjects with non-specific neck pain, aged over 18 years with an active myofascial trigger point in sternocleidomastoid, participated in the study. They were randomly assigned to treatment or control groups., Methods: TrP-DN inside or (1.5 cm) outside of the active myofascial trigger point of sternocleidomastoid., Main Outcome Measures: CMC, visual analogue scale and cervical range of motion were assessed before treatment, immediately post treatment, and 24 h, 1 week and 1 month after the intervention; the neck disability index was evaluated before treatment and 1 month later., Results: With a confidence interval of 99%, TrP-DN of sternocleidomastoid was associated with a decrease in pain after 1 week and CMC improved 1 month after the intervention (p < 0.001), when compared with baseline measurements, within the experimental group; there were no statistically significant differences between experimental and control groups., Conclusion: The effects of TrP-DN inside and outside of active myofascial trigger points did not differ in this study. Both interventions were associated with a similar temporal effect, specifically a reduction in neck pain at 1 week and an increase CMC at 1 month. However, these findings should be interpreted with caution due to the lack of a contemporaneous untreated control group.

Isometric strength and endurance performance of cervical flexor and extensor muscles were compared in women with (n = 30) and without (n = 30) idiopathic neck pain at the craniocervical and cervicothoracic axes. Strength and endurance time (time to task failure in seconds) at 50% maximal voluntary contraction were recorded in 4 directions (craniocervical flexion/extension and cervicothoracic flexion/extension) and 6 strength and endurance ratios were calculated. Participants in both groups were matched for body mass index. The idiopathic neck pain group demonstrated significantly less strength for the cervicothoracic flexors and extensors (1.58-4.7 N·m [12.4%-17.9%] less, P  < .04) and significantly less endurance time for the cervicothoracic and craniocervical flexors (10.77-10.9 s [23.3%-27.5%] less, P  < .03). The cervicothoracic extension to craniocervical flexion strength ratio was also lower in the idiopathic neck pain group ( P  = .01); however, no other strength or endurance ratio was significantly different between groups. This exploratory study suggests assessing specific performance parameters accounting for regional muscular differences in the upper and lower neck is potentially informative to understanding impairments in neck pain conditions, particularly as impairments may not be uniform across muscle groups.

It has been suggested that neck muscle strength and anticipatory cocontraction can decrease head motions during head impacts. Here, we quantify the relative angular impulse contributions of neck soft tissue to head stabilization using an OpenSim musculoskeletal model with Hill-type muscles and rate-dependent ligaments. We simulated sagittal extension and lateral flexion mild experimental head impacts performed on 10 subjects with relaxed or cocontracted muscles, and median American football head impacts. We estimated angular impulses from active muscle, passive muscle and ligaments during head impact acceleration and deceleration phases. During the acceleration phase, active musculature produced resistive angular impulses that were 30% of the impact angular impulse in experimental impacts with cocontracted muscles. This was reduced below 20% in football impacts. During the deceleration phase, active musculature stabilized the head with 50% of the impact angular impulse in experimental impacts with cocontracted muscles. However, passive ligaments provided greater stabilizing angular impulses in football impacts. The redistribution of stabilizing angular impulses results from ligament and muscle dependence on lengthening rate, where ligaments stiffen substantially compared to active muscle at high lengthening rates. Thus, ligaments provide relatively greater deceleration impulses in these impacts, which limit the effectiveness of muscle strengthening or anticipated activations.

Aim: To further the understanding of the pathophysiological mechanisms underlying tension-type headache (TTH) by comparing the endurance and strength of neck extensor muscles under acute muscle fatigue in participants with TTH and asymptomatic participants., Methods: We conducted a cross-sectional analysis of neck extensor muscle performance. Asymptomatic participants and participants with TTH were recruited via social media platforms and from the Université du Québec à Trois-Rivières community and employees. A total of 44 participants with TTH and 40 asymptomatic participants took part in an isometric neck extensor endurance task performed at 60% of their maximum voluntary contraction. Inclusion criteria for the headache group were to be older than 18 years old and to fulfil the International Headache Society classification's criteria for either frequent episodic or chronic TTH. Clinical (self-efficacy, anxiety, neck disability and kinesiophobia) and physical parameters (neck extensors maximum voluntary contraction, endurance time, muscle fatigue) as well as characteristics of headache episodes (intensity, frequency and associated disability) were collected for all participants. Surface electromyography was used to document upper trapezius, splenius capitis and sternocleidomastoids muscle activity and muscle fatigue., Results: Both groups displayed similar neck extensor muscle endurance capacity with a mean difference of 6.2 s (p>0.05) in favour of the control group (control=68.1±32.3; TTH=61.9±20.1). Similarly, participants in the headache group showed comparable neck extensor muscle strength (95.9±30.4 N) to the control group (111.3±38.7 N). Among participants with TTH, those scoring as severely incapacitated by headaches were the ones with higher neck-related disability (F[1,44]=10.77; p=0.002), the more frequent headache episodes (F[1,44]=6.70; p=0.01) and higher maximum headache intensity (F[1,44]=10.81; p=0.002)., Conclusion: A fatigue task consisting of isometric neck extension cannot efficiently differentiate participants with TTH from asymptomatic participants., 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.)

Objectives: Postural disorders disturb muscle activity and lead to joint dysfunction. This study aimed to evaluate the effects of an 8-week selective corrective exercises program on electromyography activity of scapular and neck muscles in persons with upper crossed syndrome (UCS)., Design: Randomized controlled trial., Setting: Exercise evaluation was conducted in a laboratory setting., Participant: Study recruited 30 healthy males with UCS from university students, who were then randomly divided into the control group (age = 20.14 ± 1.71 years; height = 176.86 ± 4.7 cm; BMI = 21.20 ± 1.96 kg/m 2 ) and the exercise group (age = 21.44 ± 2.06 years; height = 174.2 ± 4.0 cm; BMI = 20.62 ± 3.9 kg/m 2 )., Main Outcome Measures: Electromyography activity of upper trapezius (UT), middle trapezius (MT), lower trapezius (LT), serratus anterior (SA), and sternocleidomastoid (SCM) was recorded before and after 8-week exercise program., Results: T-test results revealed that baseline activity of SA (P < 0.05), had increased while UT (P < 0.05) and SCM (P < 0.05) activity as well as UT/SA (P < 0.05) and UT/LT (P < 0.05) ratios had decreased. In connection with these finding the effect sizes were large., Conclusion: Eight week corrective exercises balance muscles activity and can be used to manage developing upper quadrant musculoskeletal disorders in person with UCS., (Copyright © 2019 Elsevier Ltd. All rights reserved.)