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Rotational vertebral artery occlusion is a rare cause of ischemic stroke in the vertebrobasilar arteries. While computed tomography angiography (CTA) is less invasive for the diagnosis of rational vertebral artery occlusion than digital subtraction angiography and more useful for elucidating the correlation between vertebrobasilar arteries and the surrounding structure, carotid ultrasound is noninvasive and more beneficial for the real-time evaluation of the hemodynamic change with neck rotation compared to CTA. Here, we reported 2 cases of rotational vertebral artery occlusion in patients aged 81 and 38 years and proposed a novel technique for its diagnosis using ultrasound-guided CTA. We suggest that the combination of ultrasound and CTA is useful for diagnosing rotational vertebral artery occlusion, which would compensate for the disadvantages of CTA alone.

The current study evaluated the effect of a passive neck orthosis, developed for patients suffering from progressive muscular diseases, on neck muscle activity in 10 adult healthy participants. The participants performed discrete head movements involving pure neck flexion (−10 to 30°), pure neck rotation (up to 30° left and right) and combined neck flexion-rotation (−10 to 30°) in steps of 10° by moving a cursor on a screen to reach predefined targets and staying on target for 10 s. Surface electromyography (EMG) was recorded from upper trapezius and sternocleidomastoid muscles and amplitudes were averaged over the static phases in trials with and without the orthosis. Moreover, the variability in head position and time required to perform the tasks were compared between conditions. Wearing the orthosis caused significant reductions (p = 0.027) in upper trapezius activity (a change of 0.2–1.5% EMGmax) while working against gravity. The activity level of the sternocleidomastoid muscle increased (p ≤ 0.025) by 0.3–1.0% EMGmax during pure and combined rotations without any pain reported. The orthosis showed potential to reduce the activity level of the upper trapezius muscle, the main load bearing muscle of the neck. Further study will be carried out to evaluate the effect in different patient groups.

Study Design: Cross-sectional population-based study.Purpose: The study objective was to evaluate the coexistence of neck- and shoulder-disability, to establish normative scores for Neck Disability Index (NDI), Visual Analog Scale (VAS)-neck, VAS-arm, Quick Disability of Shoulder and Hand (Quick-DASH), and modified Constant score (mConstant score), and to determine the influence of psychological distress (Hospital Anxiety and Depression Scale [HADS]) on the disability measures. The authors also investigated the distribution of dysphagia across the population and its relation to the NDI scores.Overview of Literature: Several factors can adversely influence the clinical outcomes after cervical surgeries. The interaction of neck and shoulder disability in the perspective of psychological distress is not well understood.Methods: Prospective questionnaire-based assessment was performed for 1,000 participants. Questionnaires consisted of validated generic and disease-specific queries and specific questions. The survey included patients without pathologies of cervical spine/shoulders/upper extremities.Results: Mean age of participants was 39 years. The average neck VAS score was 1.2, NDI% was 7.3, arm VAS score was 0.8, QuickDASH was 6.2, mConstant score was 70.7, HADS-A score was 4.9, and HADS-D score was 3.2. The psychological scores showed a significant correlation with neck- and shoulder-disability (pr=0.3 to r=0.5). However, correlations between neck (NDI%, neck VAS score) and shoulder disability (mConstant score, arm VAS score, Quick-DASH) were stronger (pr=0.5 to r=0.6). A body mass index >35 kg/m2 influenced shoulder-disability (ppp

Swimming is a combination of upper limb and lower extremities strength exercise and also cardiovascular training. In competitive swimmers during swimming functional variations in anatomy or biomechanics and poor techniques leads to overuse injuries and micro trauma. TMD is multifactorial disorder commonly associated with masticatory and articular disabilities. According to previous studies there is a high demand on neck rotation and upper limb activities for the propulsion of the body inside the water and which negative synchronized activities of jaw and mastication structure. There is no studies have been attempted to find out the prevalence of TMD among competitive swimmers through there is a greater demand on TMJ structure due to their swimming mechanics.

Background:Assessment of individuals at risk for falling entails comprehensive neurological and vestibular examinations. Chronic limitation in cervical mobility reduces gaze accuracy, potentially impairing navigation through complex visual environments. Additionally, humans with scoliosis have altered otolithic vestibular responses, causing imbalance. We sought to determine whether dynamic cervical mobility restrictions or static cervicothoracic impairments are also fall risk factors.Methods:We examined 435 patients referred for soft-tissue musculoskeletal complaints; 376 met criteria for inclusion (mean age 52; 266 women). Patients were divided into nonfallers, single fallers, and multiple fallers, less or greater than 65 years old. Subject characteristics, dynamic cervical rotations, and static cervicothoracic axial measurements were compared between groups. Fear of falling was evaluated using the Falls Efficacy Scale-International questionnaire.Results:Long-standing cervicothoracic pain and stiffness conferred increased risk of falling. Neck rotation amplitudes decreased with longer duration musculoskeletal symptoms and were significantly more restricted in fallers, doubling the risk of falling and contributing to increased fear of falling. Mid-thoracic scoliosis amplitudes increased over time, but static axial abnormalities were not greater among fallers, although thoracic kyphoscoliosis heightened fear of falling.Conclusion:In patients at fall risk, thoracic kyphoscoliosis and dynamic neck movements should be assessed, in addition to standard vestibular and neurological evaluations. Additionally, patients with soft tissue cervicothoracic pain and restricted mobility have increased fall frequency and fear of falling, independent of other fall risk factors and should undergo complete fall risk appraisal.

Positional occlusion of the internal carotid artery is an unusual phenomenon. Reports are scarce in the literature and generally related to compression by external agents when the head is rotated. Cases with no extrinsic etiology are even more uncommon and require high suspicion to avoid misdiagnosis. We present a case of a patient with intermittent internal carotid occlusion depending on the position of the head with no external agent identified. Due to the dynamic characteristics of this presentation, diagnostic tests yielded contradictory results. Carotid ultrasound during neck rotation revealed the positional occlusion. Ultrasound is a versatile technique to explore the carotid arteries in different angles of the neck, useful if positional pathology is suspected. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s40477-020-00490-7) contains supplementary material, which is available to authorized users.

Care should be taken regarding surrounding anatomic structures during access to deep-seated extracranial schwannomas in the craniocervical junction (CCJ). Herein, we present surgical tips for extracranial schwannomas in the CCJ using the anterolateral approach. A retrospective review was performed of 3 cases of surgical treatment of extracranial schwannomas in the CCJ by the anterolateral approach, which is a presternomastoid retrojugular route to the CCJ. The combination of neck rotation and reflection of the sternocleidomastoid muscle presented a sufficient, shallow surgical field for the CCJ. We could identify tumors along the accessory nerves and internal jugular veins, and had sufficient rostrocaudal working space to resect the tumors. Two cases were enucleated total resection and 1 was subtotal resection. Two patients experienced transient postoperative vocal cord partial paralysis and 1 had transient dysphagia. These neurological complications improved within 1 month. The anterolateral approach can provide a shallow and sufficient rostral and caudal surgical window.

Purpose: This study examined the effects of the directions of neck rotation on the muscle activity of the upper trapezius and lower tra pezius while rotating a shoulder externally. Methods: Twenty-five healthy males participated in this study. The subjects were asked to rotate their shoulder externally with 90° shoulder abduction and 90° elbow flexion in three different neck rotations (neutral, ipsilateral, and contralateral) in the prone position. The muscle activities of the upper and lower trapezius were measured using surface electromyography. One way repeated measures ANOVA was used to compare the muscle activity of the upper and lower trapezius depending on the different neck turning directions. Results: In the upper trapezius, turning the neck in the ipsilateral direction while turning a shoulder externally decreased the muscle ac tivity significantly, but the muscle activity was increased significantly by turning the neck in the contralateral direction. On the other hand, in the lower trapezius, turning the neck in the ipsilateral direction increased the muscle activity significantly, but the muscle activ ity was decreased significantly by turning the neck in the contralateral direction decreased it significantly. Conclusion: When someone has an imbalance of shoulder function, turning the neck in the ipsilateral direction while turning the shoul der externally in the prone position is effective in decreasing the activity of the upper trapezius and increasing the activity of the lower trapezius. Therefore, these results could be used as basic evidence for researching patients with shoulder problems.

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.

In recent years, surface Electromyography (sEMG) signals have been effectively applied in various fields such as control interfaces, prosthetics, and rehabilitation. We propose a neck rotation estimation from EMG and apply the signal estimate as a game control interface that can be used by people with disabilities or patients with functional impairment of the upper limb. This paper utilizes an equation estimation and a machine learning model to translate the signals into corresponding neck rotations. For testing, we designed two custom-made game scenes, a dynamic 1D object interception and a 2D maze scenery, in Unity 3D to be controlled by sEMG signal in real-time. Twenty-two (22) test subjects (mean age 27.95, std 13.24) participated in the experiment to verify the usability of the interface. From object interception, subjects reported stable control inferred from intercepted objects more than 73% accurately. In a 2D maze, a comparison of male and female subjects reported a completion time of 98.84 s. ± 50.2 and 112.75 s. ± 44.2, respectively, without a significant difference in the mean of the one-way ANOVA (p = 0.519). The results confirmed the usefulness of neck sEMG of sternocleidomastoid (SCM) as a control interface with little or no calibration required. Control models using equations indicate intuitive direction and speed control, while machine learning schemes offer a more stable directional control. Control interfaces can be applied in several areas that involve neck activities, e.g., robot control and rehabilitation, as well as game interfaces, to enable entertainment for people with disabilities.

Objective Given the complex and unclear etiology of neck pain, it is important to understand the differences in central sensitization as well as psychosocial factors in individuals with chronic neck pain and healthy controls. The purpose of this study was to benchmark differences in central sensitization, psychosocial factors, and range of motion between people with nonspecific chronic neck pain and healthy controls and to analyze the correlation between pain intensity, neck disability, and psychosocial factors in people with chronic neck pain. Methods Thirty individuals with chronic neck pain and 30 healthy controls were included in this case–control study. Outcome measures were as follows: central sensitization (pressure pain threshold, temporal summation, and conditioned pain modulation), psychosocial factors (depressive symptoms, pain catastrophizing, and quality of life), and active cervical range of motion. Results People with neck pain had lower local pressure pain threshold, a decrease in conditioned pain modulation, more depressive symptoms, greater pain catastrophizing, lower quality of life, and reduced range of motion for neck rotation compared with healthy controls. In people with neck pain, moderate correlations were observed between pain intensity and quality of life (ρ = −0.479), disability and pain catastrophizing (ρ = 0.379), and disability and quality of life (ρ = −0.456). Conclusion People with neck pain have local hyperalgesia, impaired conditioning pain modulation, depressive symptoms, pain catastrophizing, low quality of life, and reduced active range of motion during neck rotation, which should be taken into account during assessment and treatment. Impact This study shows that important outcomes, such as central sensitization and psychosocial factors, should be considered during assessment and treatment of individuals with nonspecific chronic neck pain. In addition, pain intensity and neck disability are correlated with psychosocial factors.

Background: Accurate knowledge of the intervertebral center of rotation (COR) and its corresponding range of motion (ROM) can help understand development of cervical pathology and guide surgical treatment. Methods: Ten asymptomatic subjects were imaged using MRI and dual fluoroscopic imaging techniques during dynamic extension-flexion-extension (EFE) and axial left-right-left (LRL) rotation. The intervertebral segment CORs and ROMs were measured from C34 to C67, as the correlations between two variables were analyzed as well. Results: During the EFE motion, the CORs were located at 32.4 ± 20.6%, -2.4 ± 11.7%, 21.8 ± 12.5% and 32.3 ± 25.5% posteriorly, and the corresponding ROMs were 13.8 ± 4.3°, 15.1 ± 5.1°, 14.4 ± 7.0° and 9.2 ± 4.3° from C34 to C67. The ROM of C67 was significantly smaller than other segments. The ROMs were not shown to significantly correlate to COR locations (r = −0.243, p = 0.132). During the LRL rotation cycle, the average CORs were at 85.6 ± 18.2%, 32.3 ± 25.3%, 15.7 ± 12.3% and 82.4 ± 31.3% posteriorly, and the corresponding ROMs were 3.5 ± 1.7°, 6.9 ± 3.8°, 9.6 ± 4.1° and 2.6 ± 2.5° from C34 to C67. The ROMs of C34 and C67 was significantly smaller than those of C45 and C56. A more posterior COR was associated with a less ROM during the neck rotation (r = −0.583, p

The carotid artery must be avoided during stellate ganglion block. However, information on optimal neck position during the ultrasound-guided approach is limited.To investigate the relation between the target area of the procedure and the carotid artery in different neck positions.Observational study.Tertiary university.A total of 30 sides of the neck from 18 healthy participants were included.An ultrasound transducer was placed at the level of the anterior tubercle of C6 with a short-axis view for measuring the distance from the tip of the C6 anterior tubercle to the margin of the carotid artery. The participants were first examined through ultrasonography in 3 different rotational neck positions (neutral, semicontralateral rotation, and full-contralateral rotation), in the supine position. After changing to the lateral decubitus position, the measurement was performed again in the same 3 neck positions.The C6 anterior tubercle to carotid distance was measured with ultrasound.The C6 anterior tubercle to carotid distance was the longest with full-contralateral neck rotation (P .05). The distance was longer in the semicontralateral neck rotation compared with the neutral neck position (P .05). Supine or decubitus positions did not affect the distance.We suggest that the full-contralateral neck rotation posture in either the supine or decubitus position is most beneficial for avoiding damage to the carotid artery during the ultrasound-guided stellate ganglion block.Not applicable.

Eagle's syndrome (ES) refers to symptomatic elongation of the ossified styloid process. A styloid process greater than 2.5 cm in length should be considered abnormal; however, an elongated styloid process is not sufficient for a diagnosis of ES; only an abnormal styloid process in association with symptoms can confirm the syndrome. In this case report, we discuss a 54-year-old man who has come to our attention with various symptoms: dysphagia to both solids and liquids, difficulty swallowing, neck pain, and a foreign body sensation during bilateral neck rotation and mouth opening. The diagnosis is performed radiologically because conventional radiographs have many potential disadvantages, whereas, computed tomography (CT) scans and reconstructions allow the length and angulation of the styloid process to be measured and the relationship between the elongated styloid processes and adjacent anatomical structures to be evaluated. Moreover, CT allows for differential diagnosis and provides detailed information needed for surgical planning. Keywords: Eagle's syndrome, Stylalgia, Styloid process, 3D-CT

OBJECTIVES To investigate the feasibility of using 2-dimensional ultrasound (US) and shear wave elastography (SWE) to evaluate infants with late-referral congenital muscular torticollis (CMT). METHODS A total of 46 infants with late-referral CMT were enrolled and divided into 4 groups according to the degree of the passive range of motion (PROM) deficit in neck rotation. We introduced 6 metrics to represent the US features of the sternocleidomastoid muscle detected by 2-dimensional US and SWE studies. RESULTS There were no significant differences in the age at referral, sex, weight, or side of involvement between the 4 groups (P > .05). The thickness and shear modulus of the involved sternocleidomastoid muscle were positively correlated with the degree of the PROM deficit in neck rotation in late-referral infants with CMT (r = 0.71 and 0.82, respectively; P

[Purpose] Sports activity has been shown to improve postural stability and vestibular function in healthy older adults. The hypothesis was that healthy young adults undertaking sports activity will also have better postural stability and vestibular function compared with healthy young adults who do not undertake sports activity. The purpose of this study was to investigate the differences in postural stability and vestibular function between healthy young adults who undertake sports activity and those who do not undertake such activity. [Participants and Methods] Thirty-nine healthy young adults were recruited and divided into sports and non-sports groups on the basis of their response to a questionnaire concerning regular participation in sports activities over the past 12 months. In both groups, postural stability was measured during quiet standing and standing during head rotation, and dynamic visual acuity was assessed during head rotation. [Results] The results showed significant differences in postural stability during head rotation and dynamic visual acuity between the two groups, whereas no significant differences were found in postural stability during quiet standing. [Conclusion] The results suggest that healthy young adults who undertake sports activity have better postural stability during head rotation and better dynamic visual acuity. The causal effect of these differences is not clear and further investigation is warranted.

Background Although past studies using video analysis indicated that the arm tackle and head-in-front shoulder tackle are possible risks for shoulder dislocation, the underlying mechanisms of tackling-related shoulder dislocation have not been sufficiently investigated. This study aimed to analyze the kinematic aspects of these tackling motions in 1-on-1 tackles in an experimental setting using a 3-dimensional motion-capture system. Methods A total of 65 one-on-one tackles were recorded using a marker-based, automatic, digitizing motion-capture system. A documented tackle was classified into 1 of 3 types, which was decided based on the first point of contact on the ball carrier and the head position at the time of impact: shoulder tackle (reference tackle), arm tackle, and head-in-front tackle. The orientations of the head, trunk, and shoulder at impact were calculated and statistically compared with each other. Results The distribution of tackles recorded in this study was as follows: 38 shoulder, 23 arm, and 4 head-in-front tackles. In comparison with the shoulder tackle as a reference, shoulder abduction on the side of impact was higher in both the arm and head-in-front tackles, while shoulder external rotation was lower in the head-in-front tackles. In the latter type of tackle, significant decreases in neck extension and ipsilateral neck rotation were also indicated. Conclusion The kinematics in both the arm tackle and the head-in-front tackle is significantly different from that in the shoulder tackle and may represent a distinct risk factor for shoulder dislocation.

Chordomas are low-grade but locally aggressive malignant neoplasms derived from notochordal remnants. These lesions are best treated by en bloc however this is especially challenging in the upper cervical spine due to the proximity of vital structures. We present a 46 year old male whom presented to our unit complaining of progressive upper cervical axial neck pain aggravated by neck rotation, of 4 months duration. He had no symptoms of myelopathy. Examination revealed high posterior spinal tenderness and resistance to neck rotation however the patient's motor and sensory examinations were normal and he had normal gait. An inter-disciplinary team comprising Orthopedics, Neurosurgery, Maxillofacial surgery and Otorhinolaryngology took the patient for surgery. The first stage of the procedure comprised Otorhinolaryngology performing a tracheostomy and thereafter a combined Orthopedic Neurosurgical procedure involving a posterior instrumented C1–C3/C4 fusion and biopsy of the lesion. The second stage involved the maxillofacial surgeons dividing the patient's mandible to increase operative exposure. Thereafter the Orthopedic and Neurosurgical surgeons proceeded to perform a transmandibular transoral en bloc resection of the body and odontoid process of C2 which was replaced by a cage construct. The vertebral arteries were preserved and no dural breech occurred. Post operatively the patient showed no new neurology and was ambulant. He was maintained in a Philadelphia collar for 6 weeks until his fusion was complete. In conclusion this difficult case was managed successfully by thorough pre-operative planning and inter-departmental co-operation. Fortunately the lesion was isolated to the body and odontoid process of C2 which was in the patients favor lending the case towards a favorable outcome.

A 54-year-old man came to our attention complaining of occasional tinnitus and blurred vision for 2 years, particularly when driving, the symptoms were linked to rightward head rotation. Neurological examination highlighted the occurrence of the reported symptoms at the neck right torsion beyond 45° after about 10 s. After a preliminary Echo-colour Doppler, the patient underwent a dynamic contrast-enhanced MR angiography (CE-MRA) of the supra-aortic trunks. In a neutral position, vertebral artery (VA) blood flow and calibre were regular with no evidence of dominance; scans performed a in rightward head rotation beyond 60° showed a bilateral dynamic stenosis of VAs, in particular at the C5–C6 level on the right, and at the C2 level on the left (figure 1). Figure 1 Dynamic CE-MRA scans performed during right head rotation showing bilateral stenosis of the vertebral arteries at the C5–C6 level on the right (A, white arrow) and at the C2 level on the left (B, black arrow). CE-MRA, contrast-enhanced MR angiography. For diagnostic confirmation, a dynamic digital subtraction angiography (dDSA) was performed, adding selective injections of VAs at different degrees of right neck rotation. dDSA …

Natural modes and frequencies of three-dimensional (3D) deformation of the human brain were identified from in vivo tagged magnetic resonance images (MRI) acquired dynamically during transient mild acceleration of the head. Twenty 3D strain fields, estimated from tagged MRI image volumes in 19 adult subjects, were analyzed using dynamic mode decomposition (DMD). These strain fields represented dynamic, 3D brain deformations during constrained head accelerations, either involving rotation about the vertical axis of the neck or neck extension. DMD results reveal fundamental oscillatory modes of deformation at damped frequencies near 7 Hz (in neck rotation) and 11 Hz (in neck extension). Modes at these frequencies were found consistently among all subjects. These characteristic features of 3D human brain deformation are important for understanding the response of the brain in head impacts and provide valuable quantitative criteria for the evaluation and use of computer models of brain mechanics.

The rapid deformation of brain tissue in response to head impact can lead to traumatic brain injury. In vivo measurements of brain deformation during non-injurious head impacts are necessary to understand the underlying mechanisms of traumatic brain injury and compare to computational models of brain biomechanics. Using tagged magnetic resonance imaging (MRI), we obtained measurements of three-dimensional strain tensors that resulted from a mild head impact after neck rotation or neck extension. Measurements of maximum principal strain (MPS) peaked shortly after impact, with maximal values of 0.019–0.053 that correlated strongly with peak angular velocity. Subject-specific patterns of MPS were spatially heterogeneous and consistent across subjects for the same motion, though regions of high deformation differed between motions. The largest MPS values were seen in the cortical gray matter and cerebral white matter for neck rotation and the brainstem and cerebellum for neck extension. Axonal fiber strain (Ef) was estimated by combining the strain tensor with diffusion tensor imaging data. As with MPS, patterns of Ef varied spatially within subjects, were similar across subjects within each motion, and showed group differences between motions. Values were highest and most strongly correlated with peak angular velocity in the corpus callosum for neck rotation and in the brainstem for neck extension. The different patterns of brain deformation between head motions highlight potential areas of greater risk of injury between motions at higher loading conditions. Additionally, these experimental measurements can be directly compared to predictions of generic or subject-specific computational models of traumatic brain injury. Statement of Significance: Traumatic brain injury can result from the rapid acceleration of the skull, leading to deformation of brain tissue and elongation of axonal fibers. Because treatment options and prognostic models for patients are lacking, a better understanding of injury mechanisms is needed. Here, we use tagged magnetic resonance imaging to measure deformation throughout the live, human brain during non-injurious head accelerations. We present the first in vivo measurements of axonal stretch and compare MPS and axonal stretch experienced during neck rotation and neck extension. These results are important to elucidate brain regions at risk for injury. Additionally, they can be directly used to evaluate computational models of brain injury, which are used to predict risk of concussion during head impacts and design protective equipment.

Transcranial magnetic stimulation (TMS) produces motor-evoked potentials (MEP) used to infer changes in corticomotor excitability. In humans, neck rotation can probe reticulospinal input on corticomotor output. This study investigated the effect of neck rotation on MEP duration in a proximal and distal upper limb muscle and compared responses between rest and preactivation. Single-pulse TMS to motor cortex was used to evoke MEPs at two stimulus intensities in 18 healthy adults (20-40 years). Surface electromyography recorded MEPs from the non-dominant biceps brachii (BB) and first dorsal interosseous (FDI). Participants were seated with the target muscle at rest or 10% preactivated, and head rotated ipsilateral, contralateral, or in neutral position. The primary outcome was MEP tail, defined as the mean difference in MEP duration between active and rest trials. Secondary outcomes were MEP duration and amplitude. MEP tail was modulated by neck rotation in the proximal BB (P = 0.03) but not distal FDI (P > 0.19), with shorter duration during ipsilateral or contralateral rotation relative to neutral. In a neutral neck position, MEP duration was prolonged by muscle preactivation and higher TMS intensities in the FDI and BB (P 0.05). Modulation of the late portion of the MEP by rotation of the neck could indicate subcortical projections to alpha-motoneuron pools are stronger in proximal than distal upper limb muscles. These findings may have relevance for using MEP duration as a neural biomarker in neurological diseases.

There is a lack of reliable and valid measurement tools to assess neck function in infants with congenital muscular torticollis, and most physiotherapists use visual estimation, which has not been adequately tested for reliability in this population. We examined the reliability of visual estimation of head tilt and active neck rotation in the upright position, on infants with congenital muscular torticollis by physiotherapists. We recruited 31 infants and 26 physiotherapists. Therapists rated videos of infants' head position in the frontal plane (tilt) and transverse plane (active rotation) using visual estimation, on two occasions at least one week apart. Overall, inter-rater reliability was good (mean ICC, 0.68 ± 0.20; mean SEM, 5.1° ± 2.1°). Rotation videos had better reliability (mean ICC, 0.79 ± 0.14) than head tilt videos (mean ICC, 0.58 ± 0.20). Intra-rater reliability was excellent (mean ICC, 0.85 ± 0.08). Both head tilt and rotation had excellent reliability (mean ICC, 0.84 ± 0.08 for head tilt and 0.85 ± 0.09 for rotation). There was no correlation between intra-rater reliability and clinical experience.Conclusion Visual estimation had excellent intra-rater reliability in the assessment of neck active rotation and head tilt on infants with congenital muscular torticollis. Visual estimation had acceptable inter-rater reliability in the assessment of neck active rotation but not of head tilt. There was a wide variation in reliability with no correlation between reliability and clinical experience. Assessment tools for head tilt that are more psychometrically robust should be developed. What is Known: • A thorough assessment of infants presenting with torticollis is essential, using assessment tools with robust psychometric properties • Visual estimation is the most commonly used method of assessment of neck function in infants with torticollis What is New: • Visual estimation had excellent intra-rater reliability in the assessment of neck active rotation and head tilt in the upright position in videos of infants and acceptable inter-rater reliability in the assessment of rotation but not of head tilt • Physiotherapists' clinical experience had minimal relationship with reliability.

In the recent past, surface Electromyography (sEMG) signals has been effectively applied in control interfaces for robots, prosthetic hands, legs and other areas. Few works has focused on neck EMG control in spite of the neck being central to human movements and engagements. We propose a neck EMG model that estimates head movements and apply the signals to control a game developed in Unity 3D engine. The game involves randomly falling and accelerating objects. The user slides the games’ player character (paddle) using neck EMG to intercept as many objects. EMG signal is rectified and FIR filtered and used to control the position of a sliding probe of the game in real-time. The paper utilizes an equation model and a Machine Learning model to translate the filtered signal to corresponding neck rotation. From the results, all the subjects reported accuracy of over 70% which confirm the applicability of the interface and ease of use in that there is little or no calibration needed. The control model using equation showed intuitive direction and speed control while the Machine Learning scheme offered more stable direction control but limited speed control of the sliding paddle. The control interface can be applied in multiple areas that involve neck activity e.g. in rehabilitation as well as gaming interface to enable entertainment for the disabled.

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 Kendalls 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.

Objectives The aim of this study was to investigate whether the restriction in neck rotation and increased neck muscle tension could be causally related to vertigo and dizziness. Material and methods Seventy-one patients reporting vertigo and/or imbalance were divided into 2 groups: 45 subjects with unilateral restriction (R+) and 26 without restriction (R-) of cervical rotation and muscle tension in the clinical flexion-rotation test. The normal caloric test was the inclusion criterion. The control group comprised 36 healthy volunteers with no history of vertigo. The vestibulo-ocular reflex (VOR) and the cervico-occular reflex (COR) were measured through the videonystagmography (VNG) sinusoidal pendular kinetic test in the conditions of not inactivated head and immobilized head, respectively. The VNG-head torsion test (VNG-HTT) nystagmus was recorded. Results Among the reported complaints, neck stiffness, headaches and blurred vision were more frequent in the R+ group than in both the R- group and the control group. VNG revealed an increased COR gain and the presence of VNG-HTT nystagmus in the R+ group only. Similarly, only in the R+ group a positive relationship between COR and VOR was observed. Conclusions Patients with asymmetric restriction in neck rotation and increased neck muscle tension reveal the tendency to have an increased response of the vestibular system, along with co-existing COR upregulation. Further research is needed to investigate the relationships between the activation of cervical mechanoreceptors and dizziness pathomechanisms. Int J Occup Med Environ Health. 2019;32(5):723-33.

Introduction Difficulties with neck mobility often interfere with patients' activities of daily living (ADL) after cervical posterior spine surgery. The range of motion of the cervical spine decreases markedly after multilevel cervical posterior decompression and fusion (PDF). However, details regarding the limitations of cervical spine function due to postoperative reduced neck mobility after multilevel PDF are as yet unclarified. The present study aimed to clarify the quality of life and its related factors after PDF, and the optimal fixed neck position in multilevel PDF that minimizes the limitations of ADL accompanying markedly reduced postoperative neck mobility. Methods Limitations of ADL involving neck extension, rotation, and flexion were investigated in 32 consecutive patients who underwent C2-T1 PDF using the responses to the cervical spine function domain of the Japanese Orthopedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ). The EuroQol 5 Dimension, Japanese Orthopedic Association score, and five domains of the JOACMEQ were also investigated. We investigated the risk factors regarding the fixed neck position in PDF for the impossibility to perform ADL involving each of three movements using cut-off values obtained from receiver-operating characteristic curves. Results Postoperative comprehensive quality of life was significantly related to neurological improvements and to poor outcomes of cervical spine function after PDF. The significant risk factors for impossibility to perform ADL involving neck rotation were a C2-C7 lordotic angle ≥ 6° (P = 0.0057) or a proportion coefficient of C2-T1 tilt angle/C2-C7 lordotic angle ≤ 1.8 (P = 0.0024). There were no significant risk factors for impossibility to perform ADL involving neck extension or flexion. Conclusions The optimal fixed neck position in C2-T1 PDF to reduce postoperative limitations of ADL involving neck mobility is a C2-C7 lordotic angle of less than 6°, or a C2-T1 tilt angle (°) of greater than 1.8 × the C2-C7 lordotic angle (°).

Background Recently, the excellent outcomes of temporary fixation of C1-2 without fusion in the treatment of odontoid fracture had been reported. It is still unclear if this technique could achieve the equivalent outcomes as the golden standard technique of anterior screw fixation. The objective of this study is to compare the clinical outcome of two treatments of fresh type II odontoid fracture: anterior cannulated screws fixation (ACSF) versus posterior instrumentation of C1-2 without fusion (PIWF). Methods This is a retrospective study. This series included 28 males and 8 females, and the mean age was 41.5 years (range, 22 to 70 years). Eleven patients were treated with ACSF, and 25 patients with PIWF. For PIWF, the implants were removed after fracture union was confirmed at 0.75~1.5 years later. All patients underwent preoperative and serial postoperative clinical examinations at approximately 3 months, 6 months, and annually thereafter. The neck disability index (NDI) was used to assess the neck discomfort caused by the operation. The range of rotary motion was evaluated at each visit. All fractures were reassessed postoperatively with serial X-films and CT scans of the cervical spine at each follow-up visit, to evaluate screw position, fracture alignment, and fusion status. Results All patients achieved immediate spinal stabilization after surgery, and none experienced neurologic deterioration. The follow-up periods ranged from 24 to 60 months. The average range of neck rotation was dramatically lost in PIWF after fixation (46° and 89° respectively in ACSF and PIWF), and recovered to 83° after the implant was removed. The NDI in PIWF was statistically higher than that in ACSF (5 and 13% respectively in ACSF and PIWF) after the first operation and decreased to 8% 1 year after the secondary operation. The fusion rates were 90.9 and 96% respectively in ACSF and PIWF. Both groups had a case of fracture non-union. Conclusions For fresh type II odontoid fractures, high rate of fracture union can be achieved by both ACSF and PIWF. For most fresh type II odontoid fractures, anterior screw fixation was the best option for its simplicity and preservation of normal atlanto-axial rotary function. Posterior instrumentation without fusion could preserve most of the atlanto-axial rotary function and lead to moderate neck discomfort and is also a good alternative if anterior screw fixation is contraindicated.

Spatial neglect syndrome with cerebral lesions is characterized by the ina-bility to orient, report, or respond to relevant visual stimuli contralateral to the lesions. In this study, we investigated the pattern of horizontal visual search in a large space; this search was performed by patients with right hemisphere damage caused by cerebrovascular disease. The neck rotation angle and search time in each increment were continuously recorded during the task, and quantitative data of the measurements were collected. Head position during the visual search task in a large space (%) was then calculated. We set angular bands in increments of 5 degrees from the midline on the left and right sides, and calculated the total search time in each angular band. In patients with unilateral spatial neglect (USN), the search time in the angular band of 5 - 9 on the right side was significantly longer (with USN 16.7%, without USN 4.5%, t = 2.52, df = 16, p < 0.05). Furthermore, in patients with neglect in the leftmost end area in a large space, the search time was significantly shorter in the angular band of 1 - 4 degrees to the left (with neglect 13.1%, without neglect 23.7%, t = 2.13, df = 16, p < 0.05), and tended to be long in the angular band of 5 - 9 to the right. The neck rotation angle and pattern during the search task in a large field deviated slightly to the right, and the search time slightly to the left was short. We believe that these results support the rightward deviation of the search pattern and frame of USN patients.

Deformed osseous structures have been reported as rare causes of extracranial internal carotid artery (ICA) dissection, including the styloid process and the hyoid bone. Here, the authors describe the first known case of symptomatic ICA dissection caused by a giant osteophyte due to atlantoaxial osteoarthritis. The left ICA was fixed at the skull base and at the ICA portion compressed by the osteophyte, and it was highly stretched and injured between the two portions during neck rotation. The patient was successfully treated with ligation of the affected ICA following balloon test occlusion. Atlantoaxial osteoarthritis should be considered in the differential diagnosis of ICA dissection in patients with a severely deformed cervical spine.

TMJ malfunction is quiet common in swimmers. This study is done to understand the prevalence of the disorders associated with swimming in paediatric age group. According to previous studies there is a high demand on neck rotation and upper limb activities for the propulsion of the body inside the water and which negative synchronized activities of jaw and mastication structure. There is no studies have been attempted to find out the prevalence of TMD among competitive swimmers through there is a greater demand on TMJ structure due to their swimming mechanics.

Introduction Elongated styloid process syndrome represents a group of symptoms, such as recurrent throat pain and neck pain, caused by elongation of the styloid process. We report a case of elongated styloid process syndrome with prolongation of the superior cornu of the thyroid cartilage. Case presentation A 50-year-old man was referred to our clinic with the chief complaint of discomfort on the right side of his neck. He had no history of any disease. Extraoral findings indicated pain during neck rotation. Computed tomography showed prolongation of the styloid process beyond the mandibular plane and close to the hyoid. Moreover, prolongation of the superior cornu of the thyroid cartilage was detected. The discomfort during rotation of the neck was due to the stimulation by the styloid process. Styloid resection was performed using the extraoral approach under general anesthesia. Conclusion Discomfort in the neck was resolved after operation., Highlights • Elongated styloid process syndrome represents a group of symptoms. • Morphological anomalies or deviations of the thyroid cartilage may cause swallowing discomfort. • Oral and extraoral methods are used as surgical techniques for styloid hyperplasia. • There have been no reports of styloid process prolongation with hypertrophic thyroid cartilage. • There are few reports concerning the prolongation of the superior cornu of the thyroid cartilage.

The purpose of this study was to investigate the functional relationships between selected ranges of motion of the neck, upper and lower limbs, the strength of the neck and trunk muscles, postural parameters, and the motor function of children with SMA1 and SMA2—27 children, aged 6 months-15 years, with genetically confirmed spinal muscular atrophy type 1 (19 children) and 2 (8 children) undergoing pharmacological treatment. All children were examined, according to the methodology, including the motor function evaluation, measurement of selected ranges of motion, assessment of postural parameters, and measurement of neck and trunk muscle strength. The functional status of 15 children was assessed with the CHOP INTEND (CHOP group) scale and of 12 children with the HFMSE (HFMSE group). The results obtained showed that, in children examined with the CHOP scale, greater limitation of flexion in the shoulder joints was observed. As the deformation of the chest increased, the functional abilities of children deteriorated. In participants examined with the CHOP group, the ranges of neck rotation decreased with the increase of the chest deformity. In the HFMSE group, the ranges of head rotation showed a strong relationship with some parameters of muscle strength and the sum of the R coefficients. Participants showed many significant relationships between the range of motion in the neck and joints of the limbs, with more significant relationships in the CHOP group. The following conclusions were made: motor skills of children with SMA depend on muscle strength, range of motion, and deformities of the spine and chest, the development of scoliosis adversely affects the motor function, ranges of motion, and muscle strength, and movement ranges are related to motor skills and strength values.