Search

The C1 spinal nerve is a fascinating anatomic structure owing to its wide range of variations. Throughout history, understanding of the cranial and spinal nerves has probably influenced the current conception of this nerve among anatomists. Located at the craniocervical junction, the C1 spinal nerve contributes to the motor innervation of deep cervical muscles through the cervical (anterior) and Cruveilhier's (posterior) plexuses. Sensory functions of this nerve are more enigmatic; despite investigations into its dorsal rootlets, a dorsal root ganglion, and the relationships between this nerve and adjacent cranial and spinal nerves, there is still no consensus regarding its true anatomy. In this article, we review the available literature and discuss some of the developmental models that could potentially explain the wide range of variations and functions of the C1 nerve.

The article refers to testing of a biofidelic neck of anthropometric test devices, which can also be used in any field of medical, technical interest. The design of this technical system has started from the study of existing technical systems, and compared to the values obtained by the same area of the test dummy, under the same request conditions. From the study of patents, the following observations were made regarding their disadvantages - heavy construction. Many spine constructions have a multitude of mechanical devices; we cannot simulate all the movements of a human neck, but only a part of them. The biofidelic neck type technical system of a test dummy, which by its construction (both vertebrae and intervertebral discs) closely follows the technical, mechanical and constructive characteristics of the human man, and the use of elastic elements actuation to allow simulation of cervical muscles during collision tests of motor vehicles.

BACKGROUND: The aim of the study was to determine the characteristics of cervical muscle activity in different head postures when using helmet-mounted display in one fighter vs. two aircraft air combat within visual range (WVR).METHODS: Cervical EMG was measured with eight F/A-18 pilots using the Joint Helmet Mounted Cueing System (JHMCS) during air combat maneuvering. In-flight Gz acceleration and continuous head position were recorded. EMG activity is divided and presented in a matrix with three-class rotation and five-class flexion-extension postures.RESULTS: The mean muscle activity in sternocleidomastoids and cervical extensors was 28.9% of maximal voluntary contraction (MVC) and 44.8% MVC, respectively. Cervical flexor and extensor muscles are subjected to loading over MVC during high Gz sorties. Cervical rotation combined with extension exceeded muscle force-producing capacity during high Gz, resulting in a decline in muscle activity.DISCUSSION: Awkward postures, especially rotational ones, are more prone to increase loading over muscles' capacity. Overloading of muscles increases the risk of muscular and ligamentous injury. In addition, the lack of muscular support potentially leads to the Gz loading being transferred to spinal structures via intervertebral discs and the vertebral column. The JHMCS helmet seems to change the pattern of most loading muscles toward the extensor (posterior) neck muscles.Sovelius R, Mantyla M, Heini H, Oksa J, Valtonen R, Tiitola L, Leino T. Joint helmet-mounted cueing system and neck muscle activity during air combat maneuvering. Aerosp Med Hum Perform. 2019; 90(10):834-840.

Background and Aim: Vibration is a method for stimulating the vestibular system. This met­hod can unmask asymmetry between two vesti­bular systems (such as unilateral peripheral ves­tibular disorders). The occurrence of vibration-induced nystagmus (VIN) in healthy subjects can affect the diagnosis of patients with uni­lateral peripheral vestibular disorders. Thus, the evaluation of VIN in healthy subjects is critical to help the diagnosis of unilateral peripheral vestibular disorders. Methods: This study was carried out on 72 hea­lthy subjects (mean ± SD age: 27.12 ± 4.97 years) in the Auditory and Balance Clinic of Rofeideh Rehabilitation Hospital. Vibration sti­mulation with a frequency of 30 and 100 Hz was used on mastoid and posterior cervical mus­cles (PCMs) and simultaneously eye movements were recorded and analyzed using videonystag­mography. Results: The mastoid vibration with a frequ­ency of 30 and 100 Hz, respectively produced VIN in 16.67% and 27.78% of subjects and VIN observed in PCMs vibration with a frequency of 30 and 100 Hz in 4.17% and 9.72% of the subjects. Conclusion: The occurrence of VIN in healthy subjects was more probable with mastoid vib­ration in 100 Hz. In this study, VIN was pre­dominantly horizontal, its direction was toward the stimulated side, and its slow phase velocity was lower than 5 deg/s. These criteria could be used for differentiation between normal and abnormal subjects.

Purpose To understand fat distribution patterns and ectopic fat deposition in healthy adults and to provide normative data, encompassing the borders of physiological regional muscle composition. For this purpose chemical shift encoding-based water-fat Magnetic Resonance Imaging (MRI) was used for proton density fat fraction (PDFF) calculations. Material and methods 91 volunteers were enrolled (male: n = 28, age = 36.6 ± 11.4 years; female: n = 63, age = 38.5 ± 15.1 years). PDFF values combined for the multifidus, semispinalis and spinalis cervicis muscles at the level of the 3rd cervical vertebral body (C3), the 5th cervical vertebral body (C5) and the first thoracic vertebral body (Th1) were extracted. Results The paraspinal musculature at C3 (14.8 ± 10.1 % vs. 19.2 ± 11.0 %; p = 0.029) and Th1 (13.8 ± 7.0 % vs 17.7 ± 7.4 %; p = 0.011) showed significantly lower PDFF values in men compared to women. Partial correlation testing with BMI as control variable revealed highly significant correlations between the paraspinal musculature PDFF at C3 (men: r = 0.504, p = 0.007; women: r = 0.279, p = 0.028), C5 (men: r = 0.450, p = 0.019; women: r = 0.347, p = 0.006) and Th1 (men: r = 0.652, p Conclusion The present data suggest gender and age-specific fat deposition patterns of the cervical and the upper cervicothoracic paraspinal muscles and may provide reference values for pathology detection.

Introduction Patients with migraine may present a higher quantity of myofascial trigger points (MTrP) and alterations in the cervical muscles when compared to non-migraineurs. The magnetic resonance imaging (MRI) is a robust method for the study of human soft tissues and could be useful to investigate these points. Objectives To identify the presence of MTrP in the descending fibers of the trapezius muscle in women with migraine and to quantify the muscle volume by MRI, correlating it with the headache characteristics. Methods A cross-sectional analytic study was conducted among 14 women, eight in migraine group, and six in without migraine group. The presence of MTrP was evaluated using Simons' criteria, and linolenic acid capsules subsequently marked the areas. MRI was performed with 1.5T, T1-weighted sequence, and T2 in the axial, sagittal, and coronal planes. The T1-weighted sequences were performed with and without gadolinium contrast. Results The T1-weighted image analysis with and without gadolinium did not show any signal alteration in the MTrP areas in both groups. The migraine group presented more MTrP in the trapezius muscle (MD [95%CI] = 1[1; 3]; MD [95%CI] = 1[0; 2] right and left side, respectively), and a smaller muscle volume (MD [95%CI] = −198.1[-338.7;-25.6], MD [95%CI] = −149.9[-325.05;-0.13] right and left side, respectively) than non-migraineurs. The migraine frequency presented a negative strong correlation with the trapezius volumes (r = −0.812; p = 0.014). Conclusion Migraineurs present more MTrP and a smaller muscle volume than non-migraineurs. The trapezius volume is negatively correlated with migraine frequency. MRI is not a suitable outcome measure for assessing MTrP.

Objectives The Flexi-Bar and Bodyblade are oscillatory tools used in rehabilitation centers worldwide to enhance muscle activity. Because of a lack of reports on the Flexi-Bar, this study focused on erector spinae (ES) muscle activation under different conditions. Methods Twelve university students (age 21 ± 2.5 years old) were recruited in this study and were tested while using a loaded Flexi-Bar for 10 seconds. Comparison between muscle activation on the right and left sides in the cervical, thoracic, and lumbar regions was measured by electromyography during two-leg and one-leg (left and right) standing. Results The results showed that during oscillation using the right hand, the right cervical muscles showed significantly higher activation levels than the left cervical muscles, while the thoracic and lumbar regions showed significantly higher muscle activities on the left side. Conclusion The current study showed that the Flexi-Bar might be used for muscle activation and reeducation, as well as for specific exercise therapy in spinal muscle imbalance.

Thavatchai Suvarnnato,1 Rungthip Puntumetakul,1 Sureeporn Uthaikhup,2 Rose Boucaut3 1School of Physical Therapy, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand; 2School of Physical Therapy, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand; 3School of Health Sciences (Physiotherapy), University of South Australia, Adelaide, SA, Australia Background: Exercise is known to be an important component of treatment programs for individuals with neck pain. The study aimed to compare the effects of semispinalis cervicis (extensor) training, deep cervical flexor (flexor) training, and usual care (control) on functional disability, pain intensity, craniovertebral (CV) angle, and neck-muscle strength in chronic mechanical neck pain.Methods: A total of 54 individuals with chronic mechanical neck pain were randomly allocated to three groups: extensor training, flexor training, or control. A Thai version of the Neck Disability Index, numeric pain scale (NPS), CV angle, and neck-muscle strength were measured at baseline, immediately after 6 weeks of training, and at 1- and 3 -month follow-up.Results: Neck Disability Index scores improved significantly more in the exercise groups than in the control group after 6 weeks training and at 1- and 3-month follow-up in both the extensor (P=0.001) and flexor groups (P=0.003, P=0.001, P=0.004, respectively). NPS scores also improved significantly more in the exercise groups than in the control group after 6 weeks’ training in both the extensor (P

Background Magnetic resonance imaging (MRI) is used to quantify the size and structure of the architecturally complex cervical spine musculature of individuals with traumatic and idiopathic neck pain. However, to our knowledge, no scan-rescan reliability data is available on neck muscle volumes. Objectives This study investigates the intra- and inter-rater reliability and scan-rescan reliability in cervical muscle volume investigations. Design Clinical Measurement, Reliability study. Methods MRI scans were performed and repeated (within 1 h) for five asymptomatic individuals. Two raters manually traced levator scapulae, multifidus including semispinalis cervicis, semispinalis capitis, splenius capitis including splenius cervicis, and sternocleidomastoid using Analyze software (v12.0). Reliability was determined using intra-class correlation coefficients, Lin's concordance coefficient and Bland-Altman plots, with interpretation of reliability coefficients using the criteria from Fleiss. Results Intra-rater reliability of muscle quantification was excellent (ICCs ranging from 0.78 to 0.96). Inter-rater reliability was excellent for sternocleidomastoid(ICC 0.92, 95% CI 0.80, 0.97) and splenius capitis (ICC 0.77, 0.51, 0.90), and ranged from fair to good for levator scapulae (0.63, 0.18, 0.85), multifidus (0.73, 0.44, 0.88), and semispinalis capitis (0.50, 0.08, 0.77). The scan-rescan reliability was excellent for all muscles (ICCs ranging from 0.94 to 0.98). Conclusion Threats to reliability appear to be more related to manual quantification of muscles on images rather than protocols related to re-positioning a participant in the scanner and repeating the same protocol. The current findings suggest that the proposed methods can be used in establishing normative data for cervical muscle volume and comparing individuals with and without neck pain.

Background Neck pain is one of the most prevalent musculoskeletal conditions. Manual mobilization plus exercise are recommended for treating people with acute neck pain with movement coordination impairments. Therefore, it is important to consider a safe and effective coordination exercise for the cervical muscles. Using an oscillating device by holding it in the mouth might be a type of coordination exercise for the cervical muscles. Objectives This study aimed to compare the activities of the cervical muscles while using an oscillating blade held in the mouth with different swings. Methods Ten healthy male university students participated in this study (20.8 ± 0.9 years). The activities of the sternocleidomastoid and cervical extensor muscles were measured using electromyography while using an oscillating blade held in the mouth in horizontal orientation (up-down oscillation). Participants were asked to oscillate the device in one of the following swings: Cervical flexion-extension and knee flexion-extension. Both exercises were performed in a standing position. All EMG activities were normalized by EMG activities during maximum voluntary contractions of those muscles. Results The activities of the sternocleidomastoid with knee flexion-extension (5.7 ± 4.8 %) present significantly lower muscle activities (P = 0.011) than those with cervical flexion-extension (12.2 ± 8.6%). The activities of the cervical extensor muscles with knee flexion-extension (10.7 ± 6.5%) present significantly lower muscle activities (P < 0.001) than those with cervical flexion-extension (17.5 ± 10.3%). Conclusions The results of this study indicated that the exercise with knee flexion-extension had lower load for the cervical muscles than that with cervical flexionextension. The findings of this study could be basic information for grading intensity of cervical coordination exercise using an oscillating blade held in the mouth.

Russian and international research on optimization of functional state and physical performance of athletes is one of the focus areas in current sports studies. The aim of this research was to study the effectiveness of normobaric hypoxia course use in combination with cervical muscle exercise as a means to improve statokinetic stability in alpine skiers. The research involved 35 alpine skiing athletes aged 18–20 (21 subjects – experimental group, 14 subjects – control group) from the representative team of Peter the Great St. Petersburg Polytechnic University. Continuous cumulation of Coriolis acceleration (CCCA) method was used as a stimulus for the vestibular analyser. To improve statokinetic stability of the experimental group subjects, a two-week normobaric hypoxia training course in combination with cervical muscle exercises was used. The control group subjects were given “fake” normobaric hypoxia courses and performed no dedicated cervical muscle exercise. The results of the study showed that the experimental group subjects who received normobaric hypoxia in combination with cervical muscle exercise demonstrated a reliably improved CCCA tolerance time (versus initial measurements). Besides, there was a decrease in the manifestation degree of vestibulosensory, vestibulovegetative, and vestibulosomatic reactions, which generally indicates improvement of CCCA tolerance in this group of subjects. Positive dynamics of test parameters in the experimental group subjects has also been confirmed by the data of the static stabilometric test in the integrated functional computer stabilography. For instance, the open eyes test showed a reliably significant reduction in the rate of increase of the statokinesiogram length and area, oscillation amplitude of the projection of the common centre of gravity in the frontal and sagittal planes, and coefficient of asymmetry in the frontal and sagittal directions. The obtained results can justify recommendation of normobaric hypoxia course use in combination with cervical muscle exercise as a means to improve statokinetic stability in alpine skiers.

In recent years, against the background of a significant improvement in the equipment of pilots, improvement of technical characteristics of cars, a significant increase in the speed of movement of race drivers on the highway has been noted. At the same time, the psychophysiological capabilities of athletes remained virtually unchanged. This discrepancy, in turn, led to the fact that when the dynamic factors of the race and the speed of movement on the track are excessively affected, the athlete's body is affected by forces that impair not only its functional state, but also negatively affect competitive activity. To improve statokinetic stability of the experimental group subjects, a within a month normobaric hypoxia training course in combination with cervical muscle exercises was used. The control group subjects were given “fake” normobaric hypoxia courses and performed no dedicated cervical muscle exercise. The results of the study showed that the experimental group subjects who received normobaric hypoxia in combination with cervical muscle exercise demonstrated a reliably improved continuous cumulation of Coriolis acceleration (CCCA) tolerance time (versus initial measurements). Besides, there was a decrease in the manifestation degree of vestibulosensory, vestibulovegetative, and vestibulosomatic reactions, which generally indicates improvement of CCCA tolerance in this group of subjects. athletes.

The aim of this study was to determine the relationship between the thickness of masticatory and cervical muscles (temporalis, masseter and sternocleidomastoid) and facial asymmetries in young patients.21 subjects were selected, through a detailed anamnesis and clinical examination, in order to assess the normality of oral tissues, the presence of normal occlusion, the absence of alteration in tooth dimensions and of congenital or developmental anomalies of lips, mouth or face.The present investigation showed that temporalis, masseter and sternocleidomastoid muscles in untreated and growing individuals with facial asymmetries are thinner on the omolateral side when compared with controlateral normal side, but in the untreated one this value is more statistically significantly.In conclusion, the cervical muscle's thickness resulted increased in young patients Ultrasound is beginning to be recognized to have potential use in dentistry as a safe, noninvasive, comfortable and cost-effective adjunct to diagnosis by producing high-resolution images more easily than magnetic resonance (MRI) and computed tomography (CT) (27-kubo).

Objective To evaluate the effects of three different foci of attention (internal, external and mixed) on motor learning using craniocervical flexion test in inexperienced participants. Methods Ninety healthy young adults, with no experience in the task, practiced the craniocervical flexion test under three different focus of attention: a) Mixed Focus (internal plus external), b) Internal Focus, and c) External Focus. We assessed immediate, post-training, and retention (one week after the last training session) aspects of motor learning by quantifying (i) the activity of the superficial cervical flexors muscles, (ii) craniocervical range of motion, and (iii) the performance on the craniocervical flexion test. Results None of the groups showed any significant immediate, post-training, or retention effects on superficial neck flexors activity and craniocervical range of motion progression. At immediate assessment, mixed focus had greater craniocervical flexion performance than external (MD 0.9, 95%CI 0.2 to 1.5), and internal foci (MD 1.4, 95%CI 0.8 to 2.1). At post-training, mixed focus led to better craniocervical performance compared to external (MD 1.6, 95%CI 0.8 to 2.4) and internal foci (MD 2.7, 95%CI 1.9 to 3.5). External focus had better scores on the craniocervical flexion test performance than internal focus (MD 1.1, 95%CI 0.3 to 1.9). Results remained similar at retention, with mixed focus being superior to internal (MD 2.3, 95%CI 1.7 to 3) and external foci (MD 1.5, 95%CI 0.9 to 2.1) on craniocervical flexion test performance. Similarly, the performance on the craniocervical flexion test performance remained similar at retention between external and internal foci (MD 0.9, 95%CI 0.2 to 1.5). Conclusion In inexperienced asymptomatic participants, different foci of attention were not able to change cervical muscle activity and craniocervical range of motion during the craniocervical flexion test. Mixed focus was better than external and internal focus on the craniocervical flexion test. These findings were retained after one week.

RESUMO Objetivo: verificar a presença e severidade de Disfunção Temporomandibular, presença de cefaleia e cervicalgia e o limiar de dor muscular de músculos cervicais em profissionais de enfermagem sob estresse no trabalho. Métodos: 43 mulheres foram avaliadas quanto à presença e severidade de Disfunção Temporomandibular pelo instrumento Critérios de Diagnóstico para Pesquisa de Desordem Temporomandibular e pelo Índice Temporomandibular, respectivamente. Além disso, foram avaliadas quanto ao limiar de dor à pressão nos músculos cervicais por algometria e quanto à presença de cefaleia e cervicalgia. Resultados: disfunção Temporomandibular foi encontrada em 30,23% da amostra, com valor médio de escore de gravidade de 0,52. Entre as participantes com Disfunção Temporomandibular, 69,23% apresentavam depressão, 61,64% graduação I de dor crônica e Sintomas Físicos não Específicos incluindo e excluindo itens de dor em 46,15% e 61,64%, respectivamente. Cefaleia foi referida por 55,81% e cervicalgia por 60,47%. Não houve associação entre Disfunção Temporomandibular, cefaleia e cervicalgia. Os limiares de dor dos músculos cervicais apresentaram-se baixos tanto nos indivíduos com diagnóstico de Disfunção Temporomandibular quanto nos sem este diagnóstico, sem diferença significativa. O músculo esternocleidomastóideo apresentou-se com os menores limiares de dor à pressão. Conclusão: alta incidência de Disfunção Temporomandibular, cefaleia e cervicalgia foram detectadas nesta amostra. Disfunção Temporomandibular não influenciou a presença de cefaleia e/ou cervicalgia. A alta frequência de dor cervical e os baixos limiares de dor no músculo esternocleidomastóideo em todas as participantes demonstram o comprometimento dos músculos cervicais, resultante de possíveis posturas inadequadas e tensão muscular relacionadas ao estresse.

Patterns of cervical muscle activity may contribute to overuse injuries in office workers. The purpose of this investigation was to characterise patterns of upper trapezius muscle activity in pain-free office workers using traditional occupational exposure measures and a modified Active Amplitude Probability Distribution Function (APDF), which considers only periods of active muscle contraction. Bilateral trapezius muscle activity was recorded in 77 pain-free office workers for 1-2 full days in their natural work environment. Mean amplitude, gap frequency, muscular rest and Traditional and Active APDF amplitudes were calculated. All measures demonstrated fair to substantial reliability. Dominant muscles demonstrated higher amplitudes of activity and less muscular rest compared to non-dominant, and women demonstrated less muscular rest with no significant difference in amplitude assessed by Active APDF compared to men. These findings provide normative data to identify atypical motor patterns that may contribute to persistence or recurrence of neck pain in office workers. Practitioner Summary: Upper trapezius muscle activity was characterised in a large cohort of pain-free workers using electromyographic recordings from office environments. Dominant muscles demonstrated higher activity and less rest than non-dominant, and women demonstrated less rest than men. Results may be used to identify atypical trapezius muscle activity in office workers.

A population-based, cross-sectional study.The aim of this study was to quantitatively evaluate the relationship between static postural stability and fat infiltration within cervical multifidus muscle in patients with cervical spondylotic radiculopathy (CSR).CSR causes denervation by compression of nerve roots. This denervation is detected by fatty infiltration or results in fatty infiltration within muscles. Proprioceptive information in cervical multifidus muscle plays an important role in coordinated movement of postural stability; however, there have been few studies evaluating the relationship between postural stability and fat infiltration within cervical multifidus muscle among CSR patients.Sixteen CSR patients with C6 injuries and 25 age-matched healthy controls underwent magnetic resonance images to examine bilateral cervical multifidus muscle. For evaluation of fat within muscle, a muscle fat index (MFI) was calculated by using both measurement of cervical multifidus muscle and intermuscular fat. Participants' postural stability at upright position with eyes-opened and eyes-closed for 60 seconds was examined by a platform. Two parameters, the total length and the area of the center of pressure (COP), were used for evaluation.The CSR group showed significantly poorer postural stability than the control group (eyes-opened the total length; P 0.05, eyes-closed the total length; P 0.05, eyes-closed the area; P 0.05). There were significant group differences at C4, C5, and C6 MFI (P 0.05). In the CSR group, a correlation analysis demonstrated that the age, C4, C5, and C6 MFI values were significantly associated with the eyes-closed the total length of the COP (P 0.05).Fat infiltration within muscle could lead to inhibition of normal activity of musculature. The present study suggests that fat within cervical multifidus muscle could directly cause postural instability in static standing, even though the proprioceptive information has normal lower limbs.

Previous studies analyzing morphometry of posterior cervical muscles with ultrasound (US) imaging have mainly used Brightness mode (B-mode). Our aim was to investigate the intra-examiner reliability of panoramic US imaging for assessing posterior-lateral cervical muscle layers. Panoramic US images of the neck at C4/C5 level were acquired in 25 asymptomatic subjects (40% women; mean age: 24 years) by an experienced assessor. The cross-sectional area (CSA) of the upper trapezius, splenius, semispinalis, multifidi, rotators, and levator scapulae was measured from panoramic US scans on two separate days. Intra-class correlation coefficients (ICC3,1), standard error of measurement (SEM), minimal detectable change (MDC) and mean, absolute and percent errors were calculated. In general, intra-examiner reliability was excellent with ICC3,1 ranging from 0.978 (trapezius) to 0.993 (semispinalis). The SEM ranged from 0.02 (multifidus) to 0.07 (semispinalis/levator), whereas the MDC ranged from 0.05 (cervical multifidus) to 0.19 (levator/semispinalis). Absolute error was lower than 0.11 cm2 (levator/semispinalis). No differences between males and females were found. This study found that intra-examiner/rater reliability of panoramic US imaging was excellent for assessing the CSA of the posterior-lateral neck extensor muscles in asymptomatic subjects. The current findings suggest that panoramic US may be a reliable technique for examining the size of the cervical extensor muscles in both males and females.

Background To investigate the differences in clinical characteristics and long-term treatment outcomes according to antinuclear antibody(ANA) and rheumatoid factor(RF) positivity and the correlation between pain-related and hematological indices in temporomandibular disorders(TMD) patients. Methods Clinical examinations were done following the Research Diagnostic Criteria for TMD in 257 patients. Comprehensive screening along with psychological and hematological evaluations (ANA, RF, complete blood cell count, C-reactive protein[CRP] and erythrocyte sedimentation rate[ESR]) were conducted. Clinical characteristics and treatment outcomes were statistically compared between ANA/RF positive and negative groups. Results Thirty-nine patients showed ANA/RF positivity. Male patients had smaller comfortable mouth opening(CMO)(p = 0.033) and maximum mouth opening(MMO)(p = 0.016) ranges with more painful neck muscles on palpation when RF/ANA positive. Pain duration, intensity, disability days and psychological distress levels were also higher in RF/ANA positive male patients. Significant correlation was shown in ESR with pain duration(p

OBJECTIVE To compare maximal cervical muscle strength among athletes with a history of 2 or more concussions relative to athletes with no history of a previous concussion. DESIGN Athletes in the 2 groups were frequency-matched. Linear mixed models were used to test for differences in peak isometric flexion, extension, left lateral flexion, and right lateral flexion cervical muscle torque between groups. SETTING Pediatric sports medicine clinic. PARTICIPANTS Athletes with a history of multiple concussions (n = 16) and athletes with no previous concussion history (n = 17). INTERVENTIONS (OR ASSESSMENT OF RISK FACTORS OR INDEPENDENT VARIABLES):: Concussion history (group), age, sex, neck girth, and height. MAIN OUTCOME MEASURES Peak isometric torque measured with a stationary isokinetic dynamometer during a 3-second isometric hold. RESULTS There was no significant difference in peak flexion [mean difference: 21.2%, 95% confidence interval (CI): -6.6% to 57.4%, P = 0.1413], extension (mean difference: 17%, 95% CI, -6.8% to 47.1%, P = 0.1667), left lateral (mean difference: 4.4%, 95% CI, -16.9% to 31.1%, P = 0.7011), or right lateral (mean difference: 9.3%, 95% CI, -14.5% to 39.8%, P = 0.4627) isometric torque in the concussion group relative to the control group. Across all muscle actions, neck torque was significantly (P < 0.05) higher in male compared with female athletes. Increasing neck girth was also associated with a significant (P < 0.05) increase in neck torque. CONCLUSIONS There was no evidence of a consistent cervical muscle strength deficit among athletes with a history of 2 or more concussions relative to athletes with no previous history of a concussion. Age, neck girth, and sex were significantly associated with cervical muscle strength. CLINICAL RELEVANCE Isometric cervical muscle strength testing may not be a reliable test for differentiating athletes with a history of multiple concussions relative to athletes with no history of concussions in the pediatric and adolescent population. Our study presents a reliable methodology for testing cervical muscle strength among young athletes.

Increased neck strength has been hypothesized to lower sports related concussion risk, but lacks experimental evidence. The goal is to investigate the role cervical muscle strength plays in blunt impact head kinematics and the biofidelity of common experimental neck conditions. We hypothesize head kinematics do not vary with neck activation due to low short term human head-to-neck coupling; because of the lack of coupling, free-head experimental conditions have higher biofidelity than Hybrid III necks.Impacts were modeled using the Duke University Head and Neck Model. Four impact types were simulated with six neck conditions at eight impact positions. Peak resultant linear acceleration, peak resultant angular acceleration, Head Injury Criterion, and Head Impact Power compared concussion risk. To determine significance, maximum metric difference between activation states were compared to critical effect sizes (literature derived differences between mild and severe impact metrics).Maximum differences between activation conditions did not exceed critical effect sizes. Kinematic differences from impact location and strength can be ten times cervical muscle activation differences. Hybrid III and free-head linear acceleration metrics were 6±1.0% lower and 12±1.5% higher than relaxed condition respectively. Hybrid III and free-head angular acceleration metrics were 12±4.0% higher and 2±2.7% lower than relaxed condition respectively.Results from a validated neck model suggest increased cervical muscle force does not influence short term (50ms) head kinematics in four athletically relevant scenarios. Impact location and magnitude influence head kinematics more than cervical muscle state. Biofidelic limitations of both Hybrid III and free-head experimental conditions must be considered.

Background Neck muscle compositional changes may represent potential biomarkers contributing towards chronic neck-related pain and disability. Objectives To determine differences in muscle volume in the cervical muscles of individuals with chronic idiopathic neck pain compared with age- and sex-matched asymptomatic individuals, and to determine if these muscle variables relate to spinal level, side (left or right), age, sex, body mass index (BMI) or muscle strength. Study design Cross-sectional magnetic resonance imaging (MRI) study. Methods Muscle volume of five muscle (groups) from cervical levels C3-T1 in 20 pain and 17 asymptomatic participants were quantified using MRI: levator scapulae, multifidus including semispinalis cervicis, semispinalis, splenius capitus including splenius cervicis, and sternocleidomastoid. Isometric extensor and flexor muscle strength were assessed with a dynamometer. Linear mixed modelling determined differences between groups in muscle volume accounting for participant characteristics. Results Individuals with pain had greater muscle volume (adjusted mean difference 71.2 mm3 (95% CI 14.2–128.2, p = .015) of the sternocleidomastoid, accounting for spinal level, side, muscle group (extensors vs flexor), sex, age, body mass index and strength. Modelling indicated muscle volume differed between spinal levels (p Conclusion Between-group differences in cervical flexor muscle volume, and volume differences across spinal levels and muscles suggest the contribution of cervical muscles to chronic idiopathic neck pain is multifaceted and complex.

[Purpose] To present an efficient treatment regimen for patients with cervicogenic headache by comparatively analyzing the neck disability index (NDI) and cervical muscle activity after an exercise intervention. [Participants and Methods] Thirty patients with cervicogenic headache were assigned to the cranio-cervical flexion group (n=15) and cranio-cervical flexion plus transcranial direct current stimulation (tDCS) group (n=15). Intervention was administered for four weeks, after which the participants’ NDI and sternocleidomastoid muscle activity were measured. [Results] The treatment group demonstrated a significantly greater change in NDI after the intervention compared to the control group. The treatment group also showed a significantly greater change in sternocleidomastoid muscle activity than the control group. [Conclusion] Our results show that applying tDCS during cranio-cervical flexion exercise can strengthen the sternocleidomastoid muscle more effectively while improving pain and associated functions in patients with cervicogenic headache. These results would contribute towards developing a more efficient treatment for patients with cervicogenic headache.

Background: When surgical treatment of cervical vertebral malformation is considered, precise localization of compression sites is essential, but remains challenging. Magnetic motor evoked potentials (mMEP) from paravertebral muscles are useful in localizing spinal cord lesions, but no information about cervical muscle mMEP in horses is available yet. Therefore, the aim of this study was to determine the possibility, normal values, inter-and intra-observer agreement and factors that have an effect on cervical mMEP in healthy horses. Methods: Transcranial magnetic stimulation was performed on 50 normal horses and 4 (2 left, 2 right) muscle responses were recorded at the middle of each cervical vertebra (C1-C7) and additionally just caudal to C7 to evaluate cervical nerves (Cn) Cn1 to Cn8. Latency time and amplitude of the recorded mMEP were defined by both an experienced and an unexperienced operator. Results: Latency increased gradually from 14.2 +/- 1.38 ms for Cn3 to 17.7 +/- 1.36 ms for Cn8, was significantly influenced by cervical nerve (P < 0.01), gender (P = 0.02) and height (P = 0.03) and had a good intra-observer agreement. The smallest mean amplitude (4.35 +/- 2.37 mV) was found at Cn2, the largest (5.99 +/- 2.53 mV) at Cn3. Amplitude was only significantly influenced by cervical nerve (P < 0.01) and had a low intra-observer agreement. No significant effect of observer on latency (P = 0.88) or amplitude (P = 0.99) measurements was found. Conclusion: mMEP of cervical muscles in normal horses are easy to collect and to evaluate with limited intra-and inter-observer variation concerning amplitude and should be investigated in future studies in ataxic horses to evaluate its clinical value.

Background Forward head posture (FHP) and muscular dysfunction are likely contributing factors to chronic neck pain (CNP) but there are inconsistent findings on the relevance of these factors to clinical CNP characteristics. Objective To compare FHP, cervical muscles size and endurance between CNP and asymptomatic participants and to investigate their association with pain and disability and relative involvement of deep/superficial and flexor/extensor muscles. Methods Thirty-two patients with CNP and 35 asymptomatic participants were included in this case–control study. FHP in standing, extensor and flexor muscles endurance and dimensions were assessed using digital photography, clinical tests and ultrasonographic imaging, respectively. The visual analog scale and neck disability index were also used to evaluate CNP patients’ clinical characteristics. Results Deep flexor (mean difference = 0.06, 95% CI = 0.02–0.11) and extensor muscles size (mean difference = 0.07, 95% CI = 0.01–0.12) were found to be significantly smaller in CNP patients. CNP patients also demonstrated lower levels of flexor (mean difference = 14.68, 95% CI = 3.65–25.72) and global extensor endurance capacity. FHP was neither different between the groups nor correlated with any of the dependent variables. Neither FHP nor endurance was correlated with pain/disability. Extensor endurance in both groups and flexor endurance in the asymptomatic group showed significant correlations with muscles size. Conclusions FHP was found neither different between groups nor correlated with muscle performance or CNP clinical characteristics. While cervical endurance was found lower in CNP patients, it did not show any association with pain/disability. The muscular size–endurance relationship seems to become more complex in the presence of NP. While deep muscles seem to be differentially affected in the presence of CNP, the alterations do not seem to be uniform in the flexor and extensor groups.

Darbo tikslas: nustatyti smilkininio apatinio žandikaulio sąnario, kaklinės stuburo dalies ir giliųjų kaklo raumenų funkcijų sąsajas su patiriamu galvos skausmu jauno amžiaus asmenims. Tyrimo problema: daugelis pasaulio gyventojų yra jautę galvos skausmą. Galvos skausmas gali sumažinti darbingumą, pabloginti gyvenimo kokybę. Literatūroje nėra vienareikšmės nuomonės ar smilkininio apatinio žandikaulio sąnario, kaklinės stuburo dalies ir giliųjų kaklo raumenų funkciniai sutrikimai gali sukelti galvos skausmą (Speciali, 2015). Tyrimo hipotezė: manome, kad dėl netaisyklingos galvos padėties atsiradusių smilkininio apatinio žandikaulio sąnario, kaklinės stuburo dalies, giliųjų kaklo raumenų funkcijų sutrikimų, jauno amžiaus asmenys gali jausti stiprų galvos skausmą, nes šios struktūros turi anatominių ir biomechaninių sąsajų. Tyrimo metodai: 18 – 29 metų asmenims, nepatyrusiems galvos ar kaklo traumų ir nesergantiems sisteminėmis kaulų – raumenų sistemos ligomis vertinta: Judesių amplitudės: goniometrija ir liniuotės metodas; Apatinio žandikaulio judesiai: vizualiai; Raumenų jėga: dinamometrija, galvos – kaklo lenkimo testas; Raumenų ištvermė: giliųjų kaklą lenkiančių raumenų ištvermės testas; Galvos skausmas: HIT – 6 ir MIDAS klausimynai Laikysena: W. W. K. Hoeger skalė, Fox plane. Tiriamieji klausimai: 1. Įvertinti tiriamųjų patiriamą galvos skausmą. 2. Įvertinti apatinio žandikaulio šoninį nuokrypį į kairė ir dešinę atliekančių raumenų jėgos pokyčius, apatinio žandikaulio judesių amplitudes ir apatinio žandikaulio nuleidimo ir pakėlimo judesių kryptį ir apibrėžti šių rodiklių sąsajas su patiriamu galvos skausmu. 3. Įvertinti tiriamųjų giliųjų kaklo raumenų jėgą, ištvermę ir apibrėžti šių rodiklių sąsajas su patiriamu galvos skausmu. 4. Įvertinti tiriamųjų kaklinės stuburo dalies aktyvių judesių amplitudes, galvos padėtį sagitalioje plokštumoje, bendrą kūno laikyseną ir apibrėžti šių rodiklių sąsajas su patiriamu galvos skausmu. Svarbiausi tyrimo rezultatai: nustatyta statistiškai reikšminga atvirkštinė koreliacija tarp galvos skausmo įverčių ir giliųjų kaklo raumenų jėgos (r=-0.558), ištvermės (r=-0.666) bei apatinio žandikaulio nuleidimo (r=-0.554) ir šoninių nukrypimų į kairę (r=-0.407) ir dešinę (r=-.0414) puses judesių amplitudžių. Išvados: 1. Tiriamiesiems nustatytas stiprus ne migreninio tipo galvos skausmas. 2. Tarp apatinio žandikaulio šoninius nukrypimus atliekančių raumenų jėgos rodiklių nenustatytas reikšmingas skirtumas. Apatinio žandikaulio judesių amplitudžių pokyčių nenustatyta. Daugiau nei pusei tiriamųjų nustatytas sutrikęs apatinio žandikaulio nuleidimo ir pakėlimo judesio stereotipas. Nustatytas atvirkštinis reikšmingas silpnas ryšys tarp galvos skausmo įverčių ir apatinio žandikaulio šoninių nukrypimų judesių amplitudžių, vidutinis ryšys tarp galvos skausmo įverčių ir apatinio žandikaulio nuleidimo judesio amplitudės. 3. Tiriamiesiems giliųjų kaklo raumenų jėgos pokyčių nenustatyta, dešimtadaliui tiriamųjų giliųjų kaklo raumenų ištvermė buvo sumažėjusi. Nustatytas atvirkštinis reikšmingas vidutinio stiprumo ryšys tarp galvos skausmo įverčių ir kaklo giliųjų raumenų jėgos bei ištvermės. 4. Aktyvių kaklo judesio amplitudžių ir viršutinės kaklinės stuburo dalies – kaukolės kampo pokyčių nenustatyta. Pusei tiriamųjų bendra kūno laikysena buvo įvertinta kaip patenkinama, o trečdaliui kaip gera. Nustatytas atvirkštinis reikšmingas stiptus ryšys tarp galvos skausmo įverčių ir bendros kūno laikysenos. Nustatytas tiesioginis reikšmingas vidutinio stiprumo ryšys tarp galvos skausmo įverčių ir aktyvios kaklo šoninio lenkimo į kairę pusę judesio amplitudės., The aim of the study: determine the relationship between the function of the temporomandibular joint, neck, deep cervical muscles and headache in young people. Investigation problem: many people in the world have felt headache. Headache can reduce working capacity and impair quality of life. There is no one opinion in the literature, that functional disorders of the temporomandibular joint, neck and deep cervical muscles can be source of headache (Special, 2015). Study hypothesis: We believe that there is a relationship between young people’s disfunction of the temporomandibular joint, neck, deep cervical muscle and headache, because these structures distinguished to have anatomical and biomechanical correlation. Research methods: 1. Range of motion: goniometry and ruler method. 2. Visual assessment of mandibular movements. 3. Muscle strength assessment: dynamometry, cranio cervikal flextion test. 4. Muscle endurance evaluation: deep neck flexor endurance test. 5. Headache was assessed by HIT - 6 and MIDAS questionnaires. 6. Posture Assessment: W. W. K. Hoeger scale, Fox plane. Research questions: 1. To evaluate the headache. 2. To evaluate lateral deviation to right and left of strength of the masticatory muscles, the mandibular range of motion and visual evaluation of mandibular depression and elevation, furthermore determine correlation between these functions and headache. 3. To evaluate the strength and endurance of the deep cervical muscles and determine correlation between these functions and headache. 4. To evaluate the active neck range of motion, the position of the head in the sagittal plane, posture of the body and determine correlation between these functions and headache. Results of the study were a statistically significant reverse correlation between headache and deep cervical muscles strength (r = -0.558), endurance (r = -0.666) and mandibular depression (r = -0.554) and lateral excursion to the left (r = -0.407) and right (r = -. 0414) range of motions. Conclusions: 1. A severe non-migraine headache is found in the subjects. 2. There is no statistically significant difference between the muscle strength of the mandibular lateral excursion. There are no changes in mandibular range of motion. More than half of the subjects have a defined disturbance in motion of mandibular depression and elevation. A reverse statistically significant weak correlation between headache and mandibular lateral excursion range of motion and average correlation between headache and mandibular depression range of motion. 3. No changes in the strength of the deep cervical muscle, endurance in the deep cervical muscles are reduced to one tenth of subjects. A reverse statistically significant average correlation between headache and deep cervical muscle strength, endurance. 4. No changes in the active neck range of motion. No changes in the cranio - cervical angle. The posture to half of the subjects are assessed as satisfactory and one third as good. A reverse statistically significant strong correlation between headache and body posture. A direct statistically significant average correlation is found between the headache and range of the motion of the active lateral neck flexion to left.

Introduction Manual circumlaryngeal therapy (MCT) aims to correct laryngeal position and relax (para) laryngeal and cervical muscles resulting in improved voice quality. The goal of the current study was to further verify long-term effects of MCT in the treatment of Muscle Tension Dysphonia (MTD) patients based on acoustic findings and perceptual judgments. Method Twenty-eight adult female patients who had been referred to the speech therapy clinic of Khatam Hospital, Zahedan city, participated in this study. Manual circumlaryngeal therapy was undertaken. There were 15 therapy sessions, three sessions per week, each with duration of 30 minutes. Pre- and post-treatment audio recordings of sustained vowels, selected sentences, and connected speech samples were submitted to auditory-perceptual and acoustical analysis to assess the long-term (6-months) effects of the 15 treatment program. Results Acoustically, Harmonic to Noise Ratio (HNR) increased and perturbation (Jitter and Shimmer) measures decreased, and perceptually, the subjective CAPE-V ratings improved in all patients. Conclusion These results suggest that MCT can be an effective method for voice rehabilitation in patients with MTD and the changes due to the therapy were persistent over a 6-month duration following the termination of treatment sessions.

Background There is a lack of test-retest reliability studies of measurements of cervical muscle strength, taking into account gender and possible learning effects. Objective To investigate test-retest reliability of measurement of maximal isometric cervical muscle strength by handheld dynamometry. Methods Thirty women (age 20-58 years) and 28 men (age 20-60 years) participated in the study. Maximal isometric strength (neck flexion, neck extension, and right/left lateral flexion) was measured on three separate days at least five days apart by one evaluator. Results Intra-rater consistency tended to improve from day 1-2 measurements to day 2-3 measurements in both women and men. In women, the intra-class correlation coefficients (ICC) for day 2 to day 3 measurements were 0.91 (95% confidence interval [CI], 0.82-0.95) for neck flexion, 0.88 (95% CI, 0.76-0.94) for neck extension, 0.84 (95% CI, 0.68-0.92) for right lateral flexion, and 0.89 (95% CI, 0.78-0.95) for left lateral flexion. The corresponding ICCs among men were 0.86 (95% CI, 0.72-0.93) for neck flexion, 0.93 (95% CI, 0.85-0.97) for neck extension, 0.82 (95% CI, 0.65-0.91) for right lateral flexion and 0.73 (95% CI, 0.50-0.87) for left lateral flexion. Conclusion This study describes a reliable and easy-to-administer test for assessing maximal isometric cervical muscle strength.

This study aimed to determine whether excessive neck muscle tone affects hyoid bone kinetics during swallowing using videofluorography (VF) in an unnatural posture in adults.Subjects were 28 adults (12 men, 16 women; mean age, 39.75±9.50 years) who were suspected to have some symptom of swallowing disorders but did not have swallowing dysfunctional from the result of videofluorography. We first established the participant's posture a reclining wheelchair that was adjusted to a 30-degree angle with the headrest (without excessive neck muscle tone) or without headrest (with excessive neck muscle tone), used an electromyogram above the mylohyoid muscle to represent the suprahyoid muscles and above the sternohyoid muscle to represent the infrahyoid muscles to confirm neck muscle tone, and then conducted VF of swallowing measurements. Videofluorographic images were obtained when 5 mL of 50% (w/v) barium sulfate was being swallowed, and hyoid bone coordinate (the resting position and the elevated position), extent of horizontal and vertical hyoid bone elevation, as well as duration and velocity of hyoid bone elevation were evaluated (x-axis and y-axis coordinates for the resting position of hyoid bone are referred to as Xr and Yr, respectively; those for the elevated hyoid bone position induced during swallowing are referred to as Xs and Ys, respectively).In the resting position of the hyoid bone, the Yr coordinates in those with excessive neck muscle tone were significantly lower than in those without excessive neck muscle tone. Vertical hyoid bone elevation and hyoid bone elevation velocity were significantly higher with excessive neck muscle tone than without excessive neck muscle tone, whereas horizontal elevation showed no significant differences.Our findings suggest that the generation of neck muscle tone due to inappropriate posture may encourage hyoid depression and increase the extent of hyoid bone elevation, thereby increasing the risk of aspiration.

We investigated whether loss of motor neurons innervating the neck muscles contributes to dropped head (DH) in multiple system atrophy (MSA). From 75 patients with autopsy-proven MSA, we retrieved 3 who had DH (MSA-DH), and examined the 4th cervical cord segments. Neurons of the medial and lateral nuclear groups (MNG and LNG) innervate the neck and shoulder muscles, respectively. We measured the area of individual neurons in the MNG and LNG, and created an area-frequency histogram. Neurons were classified as large or small based on their area, and their total numbers in the MNG and LNG were counted. In the MNG, the numbers of both total neurons and large neurons were significantly lower in MSA patients than in the controls (214.2 ± 91.4 vs 521.3 ± 74.8, p = 0.0030, and 26.2 ± 9.1 vs 88.0 ± 34.6, p = 0.020, respectively), and were significantly lower in MSA-DH than in MSA-nonDH (139.7 ± 7.6 vs 288.7 ± 74.6, p = 0.048, and 18.0 ± 4.1 vs 34.3 ± 4.1, p = 0.016, respectively). There were no differences in the LNG neuron counts between the MSA-DH and MSA-nonDH groups. Loss of cervical motor neurons may be responsible for DH in MSA.

Background Cervical muscle alterations have been reported in patients with chronic neck pain, but the assessment of muscle morphology and strength has been overlooked in patients with degenerative cervical myelopathy (DCM). Objectives This study aimed to investigate the relationship between cervical muscle degenerative changes observed on MRI, muscle strength and symptoms severity in patients diagnosed with DCM. Design Observational study. Methods Cervical muscle measurements of total cross-sectional area (CSA), functional CSA (fat free area, FCSA) and ratio of FCSA/CSA (e.g. fatty infiltration) were obtained from T2-weighted axial MR images from C2-C3 to C6-C7 in 20 patients. Muscle strength was assessed manually using a microFET2 dynamometer. The association between cervical muscle morphology parameters, muscle strength, symptoms severity and functional status was investigated. Results Greater mean CSA and FCSA was associated with greater overall muscle strength. The mean FCSA explained 37%, 76%, 39%, 20% and 65% of the total variance in flexion, extension, right-side bending, left-side bending and overall muscle strength, respectively. The mean ratio of FCSA/CSA was not significantly associated with cervical muscle strength in any direction. However, greater FCSA/CSA ratio (e.g. less fatty infiltration) was associated with lower disability score (p = 0.02, R2 = 0.20). Conclusions Cervical muscle lean muscle mass was positively associated with cervical muscle strength in patients with DCM. Moreover, greater fatty infiltration in the cervical extensor muscles was associated with lower functional score. Such findings suggest that clinicians should pay greater attention to cervical muscle morphology and function in patients with DCM.

Purpose: A common factor in all forms of headache is the presence of myofascial trigger points (TrPs). The aim of this study was to compare the presentation of patients with cervicogenic headaches and patients with non-cervicogenic headaches in the sensitivity of TrPs in their upper trapezius, sternocleidomastoid, temporalis, and posterior cervical muscles. Method: This was a descriptive, cross-sectional study. The following variables were compared between patients with cervicogenic (n=20) and patients with non-cervicogenic (n=20) headaches: sensitivity (pain-pressure threshold) of TrPs in the upper trapezius, sternocleidomastoid, posterior cervical, and temporalis muscles (using a handheld, digital algometer); level of disability (using the Henry Ford Hospital Headache Disability Inventory questionnaire); demographics (age, sex); anthropometrics (BMI); and clinical presentation (duration and intensity of symptoms). The independent Student t-test and χ2 test were used to determine the differences between the two groups. Effect sizes (Cohen's d) were calculated when relevant. Results: The two groups were similar in level of disability, demographic and anthropometric data, and clinical presentation. However, TrP sensitivity in the right upper trapezius (p=0.006; Cohen's d=0.96) and the left upper trapezius (p=0.003; Cohen's d=1.06) muscles was higher in the cervicogenic group. Conclusions: Increased sensitivity of TrPs in the upper trapezius muscle may be used as a differentiating factor in the diagnosis of cervicogenic headaches. This finding emphasizes the importance of integrating this muscle into the rehabilitation programs of patients with cervicogenic headache.

Many people suffering from temporomandibular joint disorders (TMD) suffer from local to distant, acute or chronic pains. This is common with people suffering from craniofacial pain, accompanied by painful and non-painful symptoms, also affecting facial muscles, cervical muscles, and the muscles of the middle ear and eyes. There are multiple anatomical and neurological possibilities, which start from the articular dysfunction of the temporomandibular joint (TMJ) that can generate many conditions.