vendex and Neck-Pain

To determine the effect of small daily amounts of progressive resistance training on rapid force development of painful neck/shoulder muscles.. 198 generally healthy adults with frequent neck/shoulder muscle pain (mean: age 43.1 years, computer use 93% of work time, 88% women, duration of pain 186 day during the previous year) were randomly allocated to 2- or 12 min of daily progressive resistance training with elastic tubing or to a control group receiving weekly information on general health. A blinded assessor took measures at baseline and at 10-week follow-up; participants performed maximal voluntary contractions at a static 90-degree shoulder joint angle. Rapid force development was determined as the rate of torque development and maximal muscle strength was determined as the peak torque.. Compared with the control group, rate of torque development increased 31.0 Nm s(-1) [95% confidence interval: (1.33-11.80)] in the 2-min group and 33.2 Nm s(-1) (1.66-12.33) in the 12-min group from baseline to 10-week follow-up, corresponding to an increase of 16.0% and 18.2% for the two groups, respectively. The increase was significantly different compared to controls (P<0.05) for both training groups. Maximal muscle strength increased only ~5-6% [mean and 95% confidence interval for 2- and 12-min groups to control, respectively: 2.5 Nm (0.05-0.73) and 2.2 Nm (0.01-0.70)]. No significant differences between the 2- and 12-min groups were evident. A weak but significant relationship existed between changes in rapid force development and pain (r = 0.27, P<0.01), but not between changes in maximal muscle strength and pain.. Small daily amounts of progressive resistance training in adults with frequent neck/shoulder pain increases rapid force development and, to a less extent, maximal force capacity.

Topics: Adult; Biomechanical Phenomena; Denmark; Female; Humans; Male; Muscle Contraction; Muscle Strength; Neck Muscles; Neck Pain; Pain Measurement; Resistance Training; Shoulder Pain; Time Factors; Torque; Treatment Outcome

The present study investigated the effect of chronic neck muscle pain (defined as trapezius myalgia) on neck/shoulder muscle function during concentric, eccentric and static contraction. Forty-two female office workers with trapezius myalgia (MYA) and 20 healthy matched controls (CON) participated. Isokinetic (-60, 60 and 180 degrees s(-1)) and static maximal voluntary shoulder abductions were performed in a Biodex dynamometer, and electromyography (EMG) obtained in the trapezius and deltoideus muscles. Muscle thickness in the trapezius was measured with ultrasound. Pain and perceived exertion were registered before and after the dynamometer test. The main findings were that shoulder abduction torque (at -60 and 60 degrees s(-1)) and trapezius EMG amplitude (at -60, 0 and 60 degrees s(-1)) were significantly lower in MYA compared with CON (p<0.001-0.05). Deltoideus EMG and trapezius muscle thickness were not significantly different between the groups. While perceived exertion increased in both groups in response to the test (p<0.0001), pain increased in MYA only (p<0.0001). In conclusion, having trapezius myalgia was associated with decreased strength capacity and lowered activity of the painful trapezius muscle. The most consistent differences-in terms of both torque and EMG-were found during slow concentric and eccentric contractions. Activity of the synergistic pain free deltoideus muscle was not significantly lower, indicating specific inhibitory feedback of the painful trapezius muscle only. Parallel increase in pain and perceived exertion among MYA were observed in response to the maximal contractions, emphasizing that heavy physical exertion provokes pain increase only in conditions of myalgia.

Topics: Adult; Case-Control Studies; Chronic Disease; Electromyography; Female; Humans; Muscle Contraction; Neck Muscles; Neck Pain; Torque

A comparative analysis of electromyogram (EMG) signals of patients of cervical pain and normal controls.. To determine the differences between frequency and time domain parameters of EMG signals of patients of cervical pain and normal controls.. No diagnostic technique has emerged as a satisfactory tool for identification of spinal pain.. Seventeen male and 17 female chronic neck pain patients without cervical radiculopathy were recruited through neurology EMG clinic. The controls consisted of 30 male and 33 female subjects with no history of neck pain in the past 12 months. All subjects performed flexion, left anterolateral flexion, left lateral flexion, left posterolateral extension, and extension to pain threshold/20% maximum voluntary contraction and pain tolerance/maximum voluntary contraction in random order. The descriptive statistics for body weight normalized strength, normalized peak EMG, time to onset, time to peak, median frequency, mean power frequency, and frequency bands were calculated. These variables were subjected to analysis of variance and logistic regression to distinguish between patients and controls.. The normalized peak EMG of patients was significantly greater than those of controls in both maximal and submaximal exertions (P < 0.01). Whereas there was no consistent pattern in time to peak EMG, the time to onset of EMG revealed that the left sternocleidomastoid was always recruited before the onset of torque. A lack of significant difference in the median frequency of the 2 samples indicates that the pain did not disturb the muscle conduction velocity. Using discriminant logistic regression on frequency domain and time domain parameters, up to 97% of patients and controls were correctly classified with the resubstitution method.. Surface EMG can be used successfully in distinguishing chronic pain patients and controls, and efficacy of treatment regimes.

Topics: Adult; Analysis of Variance; Chronic Disease; Electrodes; Electromyography; Female; Humans; Isometric Contraction; Logistic Models; Male; Middle Aged; Neck Muscles; Neck Pain; Pain Threshold; ROC Curve; Sensitivity and Specificity; Torque

Isometric strength and endurance performance of cervical flexor and extensor muscles were compared in women with (n = 30) and without (n = 30) idiopathic neck pain at the craniocervical and cervicothoracic axes. Strength and endurance time (time to task failure in seconds) at 50% maximal voluntary contraction were recorded in 4 directions (craniocervical flexion/extension and cervicothoracic flexion/extension) and 6 strength and endurance ratios were calculated. Participants in both groups were matched for body mass index. The idiopathic neck pain group demonstrated significantly less strength for the cervicothoracic flexors and extensors (1.58-4.7 N·m [12.4%-17.9%] less,

Topics: Adult; Disability Evaluation; Female; Humans; Muscle Strength; Muscle Strength Dynamometer; Neck Muscles; Neck Pain; Physical Endurance; Torque

Cervical range of motion (ROM) is commonly assessed in clinical practice and research. In a previous study we decomposed active cervical sagittal ROM into contributions from lower and upper levels of the cervical spine and found level- and direction-specific impairments in women with chronic non-specific neck pain. The present study aimed to validate these results and investigate if the specific impairments can be explained by the neutral posture (defining zero flexion/extension) or a movement strategy to avoid large gravitationally induced torques on the cervical spine.. Kinematics of the head and thorax was assessed in sitting during maximal sagittal cervical flexion/extension (high torque condition) and maximal protraction (low torque condition) in 120 women with chronic non-specific neck pain and 40 controls. We derived the lower and upper cervical angles, and the head centre of mass (HCM), from a 3-segment kinematic model. Neutral head posture was assessed using a standardized procedure.. Previous findings of level- and direction-specific impairments in neck pain were confirmed. Neutral head posture was equal between groups and did not explain the direction-specific impairments. The relative magnitude of group difference in HCM migration did not differ between high and low torques conditions, lending no support for our hypothesis that impairments in sagittal ROM are due to torque avoidance behaviour.. The direction- and level-specific impairments in cervical sagittal ROM can be generalised to the population of women with non-specific neck pain. Further research is necessary to clarify if torque avoidance behaviour can explain the impairments.

Topics: Adult; Aged; Biomechanical Phenomena; Cervical Vertebrae; Chronic Pain; Female; Gravitation; Head; Humans; Middle Aged; Neck; Neck Pain; Posture; Range of Motion, Articular; Torque; Young Adult

This observational study investigated skydiver neck muscle activity during parachute opening shock (POS), as epidemiological data recently suggested neck pain in skydivers to be related to POS. Twenty experienced skydivers performed two terminal velocity skydives each. Surface electromyography quantified muscle activity bilaterally from the anterior neck, the upper and lower posterior neck, and the upper shoulders; and two triaxial accelerometers sampled deceleration. Muscle activity was normalized as the percentage of reference maximum voluntary electrical activity (% MVE); and temporal muscle activity onset was related to POS onset. Our results showed that neck muscle activity during POS reached mean magnitudes of 53-104% MVE, often exceeding reference activity in the lower posterior neck and upper shoulders. All investigated muscle areas' mean temporal onsets occurred <50 ms after POS onset (9-34 ms latencies), which is consistent with anticipatory motor control. The high muscle activity observed supports that the neck is under substantial strain during POS, while temporal muscle activation suggests anticipatory motor control to be a strategy used by skydivers to protect the cervical spine from POS. This study's findings contribute to understanding the high rates of POS-related neck pain, and further support the need for evaluation of neck pain preventative strategies.

Topics: Accelerometry; Adult; Aviation; Deceleration; Electromyography; Female; Humans; Male; Middle Aged; Neck; Neck Muscles; Neck Pain; Shoulder; Torque

The cervical spine of breakdancers is at great risk due to reversed body loading during headspin manoeuvers. This study focused on the cervical biomechanics of breakdancers and a correlation with neck pain. A standardized interview and biomechanical testing of the cervical spine of 25 participants with "headspin" ability ages 16-34 years and an age-matched cohort of 25 participants without any cervical spine problems was conducted. Neck pain history, Neck Disability Index (NDI), cervical range of motion (CROM) and cervical torque were recorded. The "headspin" group reported significantly better subjective fitness, more cervical complaints, higher pain intensity, a longer history of neck pain and a worse NDI compared to the "normal" collective. The "headspin" group showed a 2-2.5 times higher rate of neck pain than the normal population, with increased cervical flexion (p<0.05) and increased cervical torque in all planes (p<0.001). The CROM showed a negative moderate to strong correlation with NDI, pain intensity and history of neck pain. Sports medicine practitioners should be aware of headspin maneuver accidents that pose the risk of fractures, dislocations and spinal cord injuries of breakdancers.

Topics: Adolescent; Adult; Biomechanical Phenomena; Cervical Vertebrae; Dancing; Female; Humans; Male; Neck Pain; Range of Motion, Articular; Torque; Young Adult

The correlation of cervical biomechanics and neck pain in young patients has, to date, only been described in terms of small cohorts. This study focuses on the correlation of chronic neck pain and cervical biomechanics.. Neck pain, cervical range of motion (CROM) and maximal cervical torque were recorded in 746 patients with conservatively treated chronic neck pain and 3,547 participants of physiotherapy training without chronic neck pain aged 16-32 years.. The "neck pain" group had a highly significant (s < 0.001) higher neck disability index (44.7 vs. 10.4%), longer history of neck pain (3.47 vs. 0.59 years), higher pain intensity (VAS 5.93 vs. 0.93), higher pain frequency (VAS 6.98 vs. 1.09). No differences of CROM and maximal torque in the sagittal, frontal and transverse plane were found.. This study describes the largest cohort of biomechanical data of the cervical spine in young adult recorded to date. The findings demonstrate that no correlation was found between neck pain, CROM and maximal torque in the study cohort. On this basis, we conclude that the CROM and maximal cervical torque should not be used as indicators to measure the progress of chronic neck pain in physiotherapy training and sports medicine for the young adult.

Topics: Adolescent; Adult; Biomechanical Phenomena; Cervical Vertebrae; Chronic Pain; Disability Evaluation; Humans; Male; Neck Pain; Pain Measurement; Range of Motion, Articular; Torque

A comparative measurement study of in vivo cervical rotation, induced by shoulder abduction, measured using magnetic resonance imaging.. The purpose of this study was to clarify the kinematics between cervical rotation and shoulder abduction.. Although it is believed that abduction of the shoulder induces rotational movement of the cervical spine, there have been no in vivo studies to measure the influence of shoulder movement on the cervical spine at a segmental level.. Twenty-two participants [12 men, age 24.2 years (range, 20-32 years)] without history of significant cervical spine disorders were studied. Kinematic magnetic resonance imaging of the cervical spine was performed with a 0.2-T horizontally open unit. Cervical rotation was assessed with the shoulder in 0, 30, 60, 90, and 120 degrees abduction. In each position, 2 conditions were applied. Firstly no muscle contraction with the arm relaxed and supported and secondly isometric contraction of the shoulder abductors. Isometric contraction was standardized by a 2-kg adduction force applied at the wrist, perpendicular to the arm.. No statistically significant differences were found in cervical segmental rotation between each shoulder position under passive conditions (P > 0.05). When the right shoulder was abducted, with isometric contraction, at each shoulder position up to 90 degrees abduction, each cervical vertebra tended to rotate to the left and the largest vertebral movement was seen at C6, being 5.20 degrees (SD = 3.66) at 0 degrees abduction. The pattern of movement changed at 120 degrees abduction, with C1 and C2 rotating to the right.. Shoulder abduction up to 90 degrees induced left rotation throughout the cervical spine only in the presence of muscle contraction, with the largest movement occurring at C6. A contrasting pattern of upper and lower cervical rotation occurred when the arm was positioned in 120 degrees abduction.

Topics: Adult; Arm; Biomechanical Phenomena; Cervical Vertebrae; Female; Head Movements; Humans; Isometric Contraction; Magnetic Resonance Imaging; Male; Muscle Contraction; Muscle, Skeletal; Neck Muscles; Neck Pain; Range of Motion, Articular; Rotation; Shoulder Joint; Torque; Young Adult

Neck pain is common in fighter pilots due to repeated exposure to high +Gz loads, but studies comparing neck function in symptomatic and healthy fighter pilots are lacking. This study compared neck strength and EMG activity during maximal isometric contractions in a sitting position in the sagittal and coronal planes in neck pain (SP), asymptomatic fighter pilots (AP), and healthy, male, non-pilot subjects (NPS).. There were 9 SP, 10 AP, and 8 NPS, all males, who performed maximal isometric neck contractions on a specific dynamometer. Surface EMG activity was recorded bilaterally over the sternocleidomastoid and paraspinal muscles. EMG amplitude during side bending was normalized to that measured in the sagittal plane.. SP exhibited lower side-bending strength than AP (17-19%, P < 0.05). In addition, SP and NPS exhibited lower left side-bending-to-extension torque ratios (20% and 14%, respectively, P < 0.05) than AP. Similar activation level of neck flexors and extensors during side bending was found in SP and AP, whereas EMG activity of the extensors was higher than the flexors in NPS (+48%, P < 0.05). In addition, antagonistic EMG activity was higher in AP compared to NPS (26% vs. 41%, respectively, P < 0.05).. Our results suggest altered muscle function in SP compared with AP in the coronal but not in the sagittal plane. Further, AP appeared to be more efficient in the coronal plane with reference to neck extension than NPS, suggesting that some adaptations occurred due to flight exposure. These findings may have clinical implications for the management and the follow-up of neck pain in fighter pilots.

Topics: Adaptation, Physiological; Adult; Aerospace Medicine; Electromyography; Humans; Isometric Contraction; Male; Military Personnel; Muscle Strength; Neck Muscles; Neck Pain; Torque

Impairment of the cranio-cervical flexor (CCF) muscles is a feature of painful cervical spine disorders. The aim of this study was to investigate if CCF muscle impairment is present over a range of contraction intensities (maximal, moderate, low) in neck pain sufferers compared to individuals with no history of neck pain. Isometric CCF muscle strength (isometric maximal voluntary contraction (MVC)), and endurance at moderate (50% of MVC), and low (20% of MVC) loads was compared in 46 participants with neck pain (Neck Disability Index (NDI): mean+/-SD; 22.8+/-5.2) and 47 control participants (NDI: 2.6+/-2.6). Compared to the control group, the neck pain group had a significant deficit (15.9%, P=0.037) in their MVC peak torque recordings, as well as a significantly reduced capacity to sustain isometric CCF muscle contractions to task failure at 20% of MVC (35% deficit, P=0.03) and 50% of MVC (27% deficit, P=0.002). Neck pain participants also demonstrated poorer accuracy in maintaining their MVC(20) contraction at the nominated isometric CCF torque amplitude (P=0.02), compared to control participants. It would appear that impairment in isometric CCF muscle performance exists over a range of contraction intensities in neck pain sufferers, which may benefit from specific therapeutic intervention.

Topics: Adult; Case-Control Studies; Female; Humans; Isometric Contraction; Muscle Strength; Neck Muscles; Neck Pain; Pain Measurement; Physical Therapy Modalities; Range of Motion, Articular; Torque

A new method of dynamometry has been developed to measure the performance of the craniocervical (CC) flexor muscles by recording the torque that these muscles exert on the cranium around the CC junction. This report describes the method, the specifications of the instrument, and the preliminary reliability data.. For the reliability study, 20 subjects (12 subjects with a history of neck pain, 8 subjects without a history of neck pain) performed, on 2 occasions, maximal voluntary isometric contraction (MVIC) tests of CC flexion in 3 positions within the range of CC flexion and submaximal sustained tests (20% and 50% of MVIC) in the middle range of CC flexion (craniocervical neutral position). Reliability coefficients were calculated to establish the test-retest reliability of the measurements.. The method demonstrated good reliability over 2 sessions in the measurement of MVIC (intraclass correlation coefficient [ICC]=.79-.93, SEM=0.6-1.4 N x m) and in the measurement of steadiness (standard deviation of torque amplitude) of a sustained contraction at 20% of MVIC (ICC=.74-.80, SEM=0.01 N x m), but not at 50% of MVIC (ICC=.07-.76, SEM=0.04-0.13 N x m).. The new dynamometry method appears to have potential clinical application in the measurement of craniocervical flexor muscle performance.

Topics: Adolescent; Adult; Calibration; Case-Control Studies; Female; Humans; Isometric Contraction; Male; Middle Aged; Neck Muscles; Neck Pain; Physical Therapy Modalities; Reproducibility of Results; Torque

To evaluate neck flexion, extension, and, especially, rotation strength in women with chronic neck pain compared with healthy controls and to evaluate the repeatability of peak isometric neck strength measurements in patients with neck pain.. Cross-sectional.. Rehabilitation center and physical and rehabilitation medicine department at a Finnish hospital.. Twenty-one women with chronic neck pain and healthy controls matched for sex, age, anthropometric measures, and occupation.. Not applicable.. Peak isometric strength of the cervical muscles was tested in rotation, flexion, and extension.. Significantly lower flexion (29%), extension (29%), and rotation forces (23%) were produced by the chronic neck pain group compared with controls. When the repeated test results were compared pairwise against their mean, considerable variation was observed in the measures on the individual level. Intratester repeatability of the neck muscle strength measurements was good in all the 4 directions tested in the chronic neck pain group (intraclass correlation coefficient range,.74-.94). The coefficient of repeatability was 15N, both in flexion and extension, and 1.8 Nm in rotation. On the group level, improvement up to 10% due to repeated testing was observed.. The group with neck pain had lower neck muscle strength in all the directions tested than the control group. This factor should be considered when planning rehabilitation programs. Strength tests may be useful in monitoring training progress in clinical settings, but training programs should be planned so that the improvement in results is well above biologic variation, measurement error, and learning effect because of repeated testing.

Topics: Adult; Analysis of Variance; Body Height; Body Mass Index; Body Weight; Case-Control Studies; Chronic Disease; Cross-Sectional Studies; Female; Finland; Hand Strength; Head Movements; Humans; Isometric Contraction; Middle Aged; Muscle Weakness; Neck Muscles; Neck Pain; Observer Variation; Physical Therapy Modalities; Range of Motion, Articular; Rotation; Torque

Several studies have reported lower neck muscle strength in patients with chronic neck pain compared to healthy controls. The aim of the present study was to evaluate the association between the severity of neck pain and disability with neck strength and range of movement in women suffering from chronic neck pain. One hundred and seventy-nine female office workers with chronic neck pain were selected to the study. The outcome was assessed by the self-rating questionnaires on neck pain (visual analogue scale, Vernon's disability index, Neck pain and disability index) and by measures of the passive range of movement (ROM) and maximal isometric neck muscle strength. No statistically significant correlation was found between perceived neck pain and the disability indices and the maximal isometric neck strength and ROM measures. However, the pain values reported during the strength tests were inversely correlated with the results of strength tests (r=-0.24 to -0.46), showing that pain was associated with decreased force production. About two-thirds of the patients felt pain during test efforts. Pain may prevent full effort during strength tests and hence the production of maximal force. Thus in patients with chronic neck pain the results do not always describe true maximal strength, but rather the patients' ability to bear strain, which may be considerably influenced by their painful condition. The results of the present study suggest that rehabilitation in cases of chronic neck pain should aim at raising tolerance to mechanical strain.

Topics: Adult; Cervical Vertebrae; Chronic Disease; Disability Evaluation; Female; Finland; Head Movements; Humans; Isometric Contraction; Middle Aged; Muscle Contraction; Muscle Weakness; Neck Muscles; Neck Pain; Occupational Diseases; Pain Threshold; Range of Motion, Articular; Stress, Mechanical; Surveys and Questionnaires; Torque; Weight-Bearing

The purpose of the current study was twofold: (1) to determine the isometric force and electromyographic (EMG) relationship of the sternocleidomastoid, splenii and trapezii muscles bilaterally in graded and maximal exertions in the sagittal, coronal and oblique planes. and (2) to develop regression equations to predict force based on the EMG scores. A newly designed and validated cervical isometric strength testing device was used to measure the cervical muscle isometric strength and force/EMG relationship in cervical flexion, extension, bilateral lateral flexion, bilateral anterolateral flexion, and bilateral posterolateral extension, all beginning with an upright seated neutral posture. A group of 40 healthy subjects were asked to exert their cervical motions in the directions of interest, while the force output and EMG from the sternocleidomastoids, splenii, and trapezii were sampled bilaterally at 1 kHz. ANOVA, correlation, and regression analyses were carried out. The force and EMG scores were significantly different between the directions of effort (P<0.01). All regressions were significant (P<0.01). All subjects registered the highest forces in pure extension and the lowest in pure flexion, showing a gradual decrease from the posterior to anterior direction. There was a modest correlation between EMG of the investigated muscles and force (r=0.15-0.76, P<0.01). EMG output was, for example, approximately 66% higher in flexion than in extension (while force output was roughly 30% less in flexion than extension) - thus relatively more muscle activity was required in flexion than extension to generate a given force. The intermediate positions (i.e. anterolateral flexion) revealed force/EMG ratio scores that were intermediate in relation to the force/EMG ratios for pure flexion and pure extension. The cervical muscle strength and cervical muscle EMG are therefore dependent on the direction of effort.

Topics: Acceleration; Adult; Cervical Vertebrae; Electromyography; Female; Humans; Isometric Contraction; Male; Neck Muscles; Neck Pain; Torque; Whiplash Injuries

To compare physical characteristics of the cervical musculature, including maximal isometric strength of the flexors and extensors, relative isometric endurance of the extensors and the active range of motion (ROM) in extension in a group of patients seeking treatment for chronic neck pain and a group of age-matched healthy people.. Department of Medical Orthopedics, National University Hospital, Denmark.. One hundred and nineteen chronic neck-pain patients underwent physical testing for active ROM in extension, maximal isometric torque in extension and flexion and relative isometric endurance in extension before entering a clinical controlled trial studying the treatment of chronic neck pain. Their results were then compared with those of 80 age-matched healthy people.. The reliability study demonstrated good within-day and day-to-day reproducibility for active ROM. Active ROM was significantly reduced in female patients, but not in all male age groups. Patients exhibited clinically and statistically significant reductions in maximal isometric torque in both the flexors and extensors of the cervical spine, with the greatest reduction seen in the extensor muscle group. Most patient groups demonstrated a significant reduction in relative isometric endurance of the extensors.. In agreement with most low-back comparisons between patients and age-matched healthy people, the greatest relative muscular deficiencies seem to be in the extensor muscle group. Additionally, most patients exhibit a significant decrease in active ROM during extension. The clinical utility of physical measurements has not been firmly established.

Topics: Adult; Case-Control Studies; Female; Humans; Isometric Contraction; Male; Middle Aged; Neck Muscles; Neck Pain; Patient Acceptance of Health Care; Physical Endurance; Range of Motion, Articular; Reproducibility of Results; Torque