Extension and flexion in the upper cervical spine in neck pain patients

Reliability and measurement properties of upper cervical flexion-extension range of motion testing in people with cervicogenic headache and asymptomatic controls

OBJECTIVE

The objective was to determine reliability of sagittal plane range of motion (ROM) assessment in a healthy population and in people with cervicogenic headache (CGH).

METHODS

Upper cervical flexion/extension ROM was measured using an iPhone magnetometer sensor and retraction/protraction ROM measured by linear displacement. Two independent raters evaluated these movements in 33 subjects with CGH and 33 age and gender matched asymptomatic healthy controls on two occasions. Measurement procedures were standardized; and the order of testing randomized. Reliability, standard error of measurement (SEM) and minimum detectable change (MDC) were calculated.

RESULTS

Subjects comprised 30 females and 36 males. The iPhone method demonstrated high reliability (ICC >0.82) with SEM values ranging from 0.62 to 1.0 and MDC values ranging from 1.70 to 4.81 respectively. Evaluation of linear displacement demonstrated moderate reliability (ICC >64). with SEM values ranging from 0.38 to 1.91 and MDC values ranging from 1.05 to 1.63 respectively. Compared to healthy controls, upper cervical flexion, retraction and protraction ROM was significantly less in the CGH group with mean difference of 6.50°, 1.52 cm and 2.34 cm respectively.

DISCUSSION

Upper cervical spine sagittal plane ROM can be measured with moderate to high reliability and was found to be more restricted in people with CGH.

Neck Kinematics in Patients With Chronic Mechanical Neck Pain: An Observational Study to Explore the Integration of Multiple Influencing Factors Through a Bayesian Model-Based Approach

The aim of this observational, cross-sectional study is to evaluate potential differences in kinematics, specifically range of motion (ROM) and velocity, during planar cervical movements between patients with non-traumatic chronic neck pain and disability and asymptomatic controls, while accounting for potential influencing variables of age, sex and fear of movement. The influence of pain intensity, neck disability, age, sex or fear of motion on kinematics was analyzed through robust multivariate Bayesian regression models fitted using the brms library in R. Forty-three patients with neck pain (aged 36.70 ± 13.75 years; 10 men and 33 women) and 42 asymptomatic participants (aged 32.74 ± 13.24 years; 25 men and 17 women) completed the study protocol. The presence of neck pain/disability was associated with lower ROM and peak velocity during all planar movements when considering the influence of age, sex or fear of motion, with standardized regression coefficients that had a small effect size (ranged from 0.11 to 0.28) and estimated differences of less than 2.21° in ROM and 25.61°/s in peak velocity. Although patients with chronic mechanical neck pain showed reduced ROM and peak velocity, the small effect sizes and the low estimated differences between groups question the relevance and clinical usefulness of kinematic analysis of planar movements in samples of patients similar to those included in our study. It is probable that there are differences between the groups, but it is insufficient to rely solely on kinematic variables for patient discrimination. This limitation likely arises from the substantial variability in patient kinematics.

Cervical musculoskeletal impairments and pressure pain sensitivity in office workers with headache

BACKGROUND

Office workers are specifically vulnerable to headache conditions. Neck pain is reported by almost 80% of patients with headaches. Associations between currently recommended tests to examine cervical musculoskeletal impairments, pressure pain sensitivity and self-reported variables in headache, are unknown. The aim of this study is to evaluate whether cervical musculoskeletal impairments and pressure pain sensitivity are associated with self-reported headache variables in office workers.

METHODS

This study reports a cross-sectional analysis using baseline data of a randomized controlled trial. Office workers with headache were included in this analysis. Multivariate associations, controlled for age, sex and neck pain, between cervical musculoskeletal variables (strength, endurance, range of motion, movement control) and pressure pain threshold (PPT) over the neck and self-reported headache variables, such as frequency, intensity, and the Headache-Impact-Test-6, were examined.

RESULTS

Eighty-eight office workers with a 4-week headache frequency of 4.8 (±5.1) days, a moderate average headache intensity (4.5 ± 2.1 on the NRS), and "some impact" (mean score: 53.7 ± 7.9) on the headache-impact-test-6, were included. Range of motion and PPT tested over the upper cervical spine were found to be most consistently associated with any headache variable. An adjusted R2 of 0.26 was found to explain headache intensity and the score on the Headache-Impact-Test-6 by several cervical musculoskeletal and PPT variables.

DISCUSSION

Cervical musculoskeletal impairments can explain, irrespective of coexisting neck pain, only little variability of the presence of headache in office workers. Neck pain is likely a symptom of the headache condition, and not a separate entity.

Impact of Movement Control Training Using a Laser Device on the Neck Pain and Movement of Patients with Cervicogenic Headache: A Pilot Study

This study verified the effect of movement control training using a laser device on the neck pain and movement of patients with cervicogenic headache. A total of twenty outpatients recruited from two Busan hospitals were equally divided into two groups. The experimental group underwent movement control training with visual biofeedback, while the control group performed self-stretching. Both groups received therapeutic massage and upper cervical spine mobilization. A four-week intervention program was also conducted. Measurement tools including the cervical flexion-rotation test, visual analog scale, Headache Impact Test-6, pressure pain threshold, range of motion, sensory discrimination, and Neck Disability Index helped assess the participating patients before and after the intervention. Additionally, the Wilcoxon signed-rank test and the Mann-Whitney U test helped determine inter and intra-group variations, respectively, before and after the intervention. Most of the measurement regions revealed significant changes post-intervention within the experimental group, while only the cervical flexion-rotation test, visual analog scale, Headache Impact Test-6, and Neck Disability Index indicated significant changes post-intervention within the control group. There were also considerable inter-group differences. Thus, movement control training using a laser device more effectively improves neck pain and movement of patients with cervicogenic headache.

A Novel Device for Assessment and Treatment of Upper Cervical Spine: Test-Retest Reliability Study

INTRODUCTION

Neck pain is one of the most frequent reasons for consultation in primary care. Clinicians evaluate different variables, including movement and cervical strength, to determine the prognosis of patients. Usually, the tools employed for this purpose are expensive and bulky, or more than one is needed. This study aims to describe a novel device designed to assess the cervical spine and describe its test-retest reliability.

METHODS

The Spinetrack device was designed to measure the strength of deep cervical flexor muscles and the chin-in and chin-out movement of the upper cervical spine. A test-retest reliability study was developed. The flexion, extension and strength needed to move the Spinetrack device were registered. Two measurements were developed, with one week between each assessment.

RESULTS

Twenty healthy subjects were evaluated. The strength of the deep cervical flexor muscles in the first measurement was 21.18 ± 3.15 Newtons, the displacement movement during chin-in movement was 12.79 mm ± 3.46 and the displacement during chin-out movement was 35.99 mm ± 4.44. The test-retest reliability of strength was ICC 0.97 (95% CI (0.91-0.99)).

CONCLUSION

The Spinetrack device has shown excellent test-retest reliability values for the measurement of the strength of the cervical flexor muscles and for the chin-in and chin-out movements.

Effect of non-specific neck pain on the path of the instantaneous axis of rotation of the neck during its flexion-extension movement

Non-specific neck pain is a common musculoskeletal disorder with a high prevalence and involves impaired joint movement pattern. Therefore, this study aimed to compare the trajectory of the instantaneous axis of rotation(IAR) in flexion-extension movements of the neck between people with and without nonspecific neck pain, using functional data analysis techniques. Furthermore, possible relationships between neck kinematics and perceived pain and disability were explored. Seventy-three volunteers participated in this cross-sectional study. They were allocated in a non-specific pain group (PG, n = 28) and a control group (CG, n = 45). A cyclic flexion-extension movement was assessed by a video photogrammetry system and numerical and functional variables were computed to analyze IAR trajectory during movement. Moreover, to explore possible relationships of these variables with pain and neck disability, a visual analogue scale (VAS) and the neck disability index (NDI) were used. The instantaneous axis of rotation trajectory during the flexion-extension cyclic movement described a path like Greek letter rho both in the CG and the PG, but this trajectory was shorter and displaced upward in the PG, compared to the CG. A reduction of the displacement range and a rise in the vertical position of the IAR were related to VAS and NDI scores. Non-specific neck pain is associated with a higher location of the instantaneous axis of rotation and a decrease in length of the path traveled during the flexion-extension movement. This study contributes to a better description of neck movement in people with non-specific neck pain, which would help to plan an individualized treatment.

Association between Age, Sex and Cervical Spine Sagittal Plane Motion: A Descriptive and Correlational Study in Healthy Volunteers

Active motion examination of patients with cervical spine-related pathologies is necessary to establish baseline function, set physical therapy goals, and choose interventions. This study investigated the sagittal plane active range of motion (ROM) of the global (GCS) and upper cervical spine (UCS) in relation to age and sex in healthy volunteers. One hundred twenty-two volunteers aged 18 to 75 years participated. Volunteers were excluded if they displayed any characteristic that could affect cervical spine ROM. GCS and UCS flexion and extension were each measured three times using a CROM device. Linear regression models (LRMs) were developed to explore the relationships between age and sex and GCS and UCS ROM. The LRM for age showed a decrease in GCS flexion (-2.01°), GCS extension (-3.33°), and UCS extension (-1.87°) for every decade of increasing age. The LRM for sex showed that men displayed less ROM than women in GCS extension (-6.52°) and UCS extension (-2.43°). These results suggest an age-related loss of sagittal plane GCS ROM and UCS extension ROM, and sex-related differences in GCS and UCS extension with women having greater motion than men.

Kinematic analysis of sensorimotor control during the craniocervical flexion movement in patients with neck pain and asymptomatic individuals: a cross-sectional study

BACKGROUND

Patients with craniocervical pain have shown reduced performance in the craniocervical flexion test (CCFT). However, there is limited evidence of other possible kinematic alterations not assessed in the context of the CCFT. Previous studies on other functional or planar movements have reported alterations in sensorimotor control (e.g., range of motion [ROM], velocity, or smoothness) in subjects with neck pain. The objective of this study was to explore the association between sensorimotor control variables associated with craniocervical flexion movement and different characteristics related to pain, age, disability, and fear of movement in individuals with non-traumatic chronic neck pain and asymptomatic controls.

METHODS

This was an observational, cross-sectional study in patients with non-traumatic neck pain and asymptomatic participants. Regression models were used to assess whether descriptive characteristics of the sample, including: (a) age, (b) intensity of pain, (c) neck disability, (d) chronicity of pain, and (e) fear of movement could explain sensorimotor control variables such as ROM, velocity, jerk, head repositioning accuracy, and conjunct motion. All these variables were recorded by means of light inertial measurement unit sensors during the performance of three maximal repetitions of full range craniocervical flexion in the supine position.

RESULTS

A total of 211 individuals were screened and 192 participants finished the protocol and were included in the analyses. Participants had an average age of 34.55 ± 13.93 years and included 124 patients with non-traumatic neck pain and 68 asymptomatic subjects. Kinesiophobia partially explained lower craniocervical flexion ROM (p = .01) and lower peak velocity in flexion (P < .001). Age partially explained increased craniocervical extension ROM (P < .001) and lower peak velocity in flexion (P = .03). Chronicity partially explained increased lateral flexion conjunct motion (P = .008). All models showed low values of explained variance (< 32%) and low absolute values of regression coefficients.

CONCLUSIONS

This study did not find a clear relationship between population characteristics and sensorimotor control variables associated with the craniocervical flexion movement. Kinesiophobia might have some association with reduced ROM in craniocervical flexion, but further research in this field is needed in large samples of patients with higher levels of kinesiophobia pain or disability.

Effects of diacutaneous fibrolysis in patients with tension-type headache: A randomized controlled trial

BACKGROUND

Manual therapy appears to be effective for the relief of tension-type headache (TTH), just as diacutaneous fibrolysis (DF) has shown to be a beneficial technique for the relief of symptoms in other dysfunctions. However, no studies have evaluated the potential beneficial effect of DF in TTH. The aim of this study is to analyze the effect of three sessions of DF in patients with TTH.

METHODS

Randomized controlled trial in 86 subjects (43 intervention/ 43 control group). The headache frequency, the headache intensity, the pressure pain thresholds (PPTs) at trapeziometacarpal joint, upper trapezius, suboccipital, frontal and temporal muscles, parietal sutures and the cervical mobility were measured at baseline, at the end of the third intervention and one-month after the last intervention.

RESULTS

Statistically significant differences with p values <0.05 were observed between groups in favor of the intervention group in the one-month follow-up in the following variables: headache frequency, headache intensity, flexion, extension, right and left side-bending, right and left rotation, PPTs in left trapeziometacarpal joint, right suboccipital muscle, right and left temporal muscle, left frontal muscle and right and left parietal.

CONCLUSIONS

DF provides a beneficial effect in reducing headache frequency, relieving pain, and improving cervical mobility in patients with TTH.

Association between age, sex and cervical and upper cervical rotation tests. Descriptive and correlational study in healthy volunteers

Background

Active cervical spine rotation (ACROM Rot) shows cervical rotation and flexion rotation test (FRT); side-bending rotation test (SBRT) and upper cervical axial rotation test (C0-C2ART) are described to measure upper cervical rotation. The objectives of this study are (1) to describe the normal range of motion (ROM) of ACROM Rot, and the ROM in FRT, SBRT and C0-C2ART tests; (2) to explore the correlation among the four tests and (3) to investigate the influence of age and sex in their ROM.

Methods

A cross-sectional study was carried out with healthy volunteers from 18 to 75 years of age. Tests were measured using a CROM device and a bubble inclinometer. Descriptive analysis was performed to establish normative data for the ROM tests. Correlation analysis was conducted to understand the relation between upper and global cervical rotation ROM and among the three upper cervical rotation tests. Linear regression models were developed to understand the influence of age and sex in the ROM of all tests.

Results

Normative values were obtained from 122 healthy volunteers (50% male), by sex and age strata. The degree of correlation ranged between 0.582 (p < 0.01) for FRT and ACROM Rot left and 0.217 (p < 0.05) for SBRT and C0-C2ART left. Linear regression models showed the influence of sex for ACROM Rot right (men -4.64° less than women), SBRT (men -4.1° less than women) left and C0-C2ART right and left (men -2.24° and -1.78° less than women). The age influenced rotation ROM with a decrease for every 10 years of -2.11° and -1.96° for ACROM Rot right and left, of -1.72° and -1.26° for FRT right and left and -0.58° and -0.41° for C0-C2ART right and left in the linear regression models. No association was found between age and SBRT (p = 0.63 for right SBRT and p = 0.49 for left SBRT).

Conclusion

Weak-to-moderate correlation was found between the upper cervical spine rotation tests and with the ACROM. Women had a larger ROM in ACROM Rot right, SBRT left and C0-C2ART. Decreases in ROM related with age were observed for ACROM Rot, FRT and C0-C2ART but not for SBRT.

A perspective on the use of the cervical flexion rotation test in the physical therapy management of cervicogenic headaches

BACKGROUND

The Cervical Flexion-Rotation Test (CFRT) is widely used in the assessment of upper cervical spine mobility impairments and in the diagnosis of cervicogenic headache (CGH) by physiotherapist. Many studies investigated its different properties, and the results show that the CFRT has good construct validity in the measurement of C1-C2 rotation as well as good to excellent reliability.

PURPOSE

In this theoretical paper, we explore the value and point out two methodological issues associated to the CFRT, one related to the procedures and another related to its diagnostic accuracy.

RESULTS

Our analysis indicate that there are many confounding factors that could affect the CFRT cut-off's accuracy, which are likely to overestimate the diagnosis properties of CFRT. Potential solutions are discussed. Moreover, the gold standard (manual examination) used to examine the validity of the CFRT for the diagnosis of CGH appears to be far from perfect - we could argue that the diagnostic properties of the CFRT for CGH might be biased and the likelihood ratios are likely to be overestimated. However, it could be relevant to explore if results of the CFRT could be considered as a treatment-effect modifier. Maybe the CFRT could be more valuable as a prognostic factor?

CONCLUSION

The quality of evidence supporting the validity of the CFRT is most likely biased. In the absence of a better gold standard, maybe the CFRT could be a more valuable test to establish the patient's prognosis and help the clinician to choose the most appropriate treatment options.

Inter-rater reliability, discriminatory and predictive validity of neck movement control tests in office workers with headache and/or neck pain

BACKGROUND

Movement control tests (MCTs) are clinical tests to evaluate impairment of movement and associated neuromuscular control and are commonly used to evaluate people with neck pain or headache conditions. The aim of this study was to establish inter-rater reliability as well as discriminatory and predictive validity for seven MCTs of the upper (UCS) and lower cervical spine (LCS) in office workers with headache or neck pain.

METHODS

Seven MCTs of the UCS (3) and LCS (4) were performed at baseline on 140 office workers which were included in a cluster randomized controlled trial. The occurrences of headache and neck pain were established at baseline (discriminatory validity) and at a 15-month follow-up (predictive validity). Inter-rater-reliability was established in a separate cross-sectional study.

RESULTS

MCTs showed slight to almost perfect inter-rater reliability but limited discriminatory (baseline) and limited to small predictive validity (15-month follow up) for different subgroups of office workers with headache and/or neck pain. MCTs of the UCS showed limited discriminatory validity, especially for rotation in participants with headache and neck pain compared to those with headache only (Negative Likelihood-ratio: 0.82, 95% CI: 0.69-0.98). Participants with neck pain only and ≥1/4 positive MCTs for the sagittal plane had an increased risk for future neck pain (Relative risk: 3.33, 95% CI: 1.05-10.56).

DISCUSSION

MCTs of the UCS and LCS are reliable but have only limited to small validity to predict future headache events in office workers. Insufficient sagittal plane movement control may predict neck pain relapses in the future.

Development and validation of the ND10 to measure neck-related functional disability

Background

Previous neck-specific patient-reported outcome measures (PROMs) have tended to measure both symptoms and disability. This multi-staged study developed and evaluated a neck-specific PROM focusing on functional disability.

Methods

This study integrated findings from systematic reviews on neck-specific outcome measures, patient interviews, qualitative studies on neck disability, and iterative item testing to develop a 10-item measure of neck-related disability (ND10). Content validity was assessed by classifying items using the International Classification of Functioning, Disability and Health (ICF) and perspective linking. Patients (n = 78) with neck pain completed cognitive interviews, exploring items of the Neck Disability Index (NDI) and ND10, and completed structured questions related to literacy and relevance. Test–retest reliability and internal consistency were evaluated using intraclass correlation coefficients, Bland Altman graphs, and Cronbach’s alpha. Concurrent convergent validity was evaluated by comparing the ND10 to the NDI, Single Assessment Numeric Evaluation (SANE), and Disabilities of the Arm, Shoulder and Hand (DASH). Known group validity was determined by comparing ND10 scores from patients, who rated their neck as more or less than 1/2 of “normal” on the SANE, using t-tests.

Results

The ND10 requires respondents to make rational judgements about their neck-related body function and disability. It has high internal consistency (0.94) and re-test reliability (0.87; SEM = 3.2/100; MDC = 7.5); and no re-test bias (mean re-test difference of 0.6). It followed expected correlation patterns, being highly correlated with related multi-item PROMs (r = 0.85–0.91), and moderately correlated to the single-item SANE. More patients agreed that the ND10 was easily readable than did so for the NDI (84% vs 68%; p < 0.05). All the PROMs distinguished the patients who perceived themselves as being abnormal/normal defined by a dichotomized SANE (p < 0.01).

Conclusion

The ND10 is reliable and valid for measuring neck-related functional disability. Longitudinal and cross-cultural translation studies are needed to support future use.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05556-7.

Measurement properties of smartphone applications for the measurement of neck range of motion: a systematic review and meta analyses

Background

Smartphone applications offer an accessible and practical option to measure neck range of motion (ROM) and are becoming more commonly used in clinical practice. We assessed the validity, reliability, and responsiveness of smartphone applications (apps) to measure neck ROM in people with and without neck pain.

Methods

A comprehensive electronic search strategy of the main electronic databases was conducted from inception until June 2021. The identified studies investigated apps which measured neck ROM, and evaluated their validity, reliability, or responsiveness, in adult participants with neck pain or asymptomatic individuals. Two independent reviewers determined eligibility and risk of bias following COSMIN guidelines. The quality of evidence was assessed according to the GRADE approach.

Results

Eleven studies, with a total of 376 participants were included. Three types of apps were identified: clinometer apps, compass apps, and other apps of ‘adequate’ to ‘doubtful’ risk of bias. A meta-analysis revealed ‘good’ to ‘excellent’ intra-rater and inter-rater reliability across the three types of apps. The overall validity was rated from ‘moderate’ to ‘very high’ across all apps. The level of evidence was rated as ‘low’ to ‘very low’.

Conclusion

Smartphone applications showed sufficient intra-rater reliability, inter-rater reliability, and validity to measure neck ROM in people with and without neck pain. However, the quality of evidence and the confidence in the findings are low. High-quality research with large sample sizes is needed to further provide evidence to support the measurement properties of smartphone applications for the assessment of neck ROM.

Study registration

Following indications of Prisma-P guidelines, this protocol was registered in PROSPERO on 1/05/2021 with the number CRD42021239501.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05066-6.

An upper cervical spine treatment protocol for cervicogenic dizziness: a randomized controlled trial

INTRODUCTION

Physiotherapy is a common treatment used for cervicogenic dizziness (CD). Treatment of the cervical spine using manual therapy techniques shows moderate evidence in favor of its use. International criteria for the treatment of the cervical spine have been described. Detecting patients' contraindications is the most important safety consideration. International criteria and recommendations for treatment of the cervical spine have been described, as well as safety criteria. A safe traction-manipulation intervention protocol is therefore possible. However, the effects of this protocol on dizziness intensity and dizziness-related disability have not been studied.

OBJECTIVE

To analyze the effects of a traction-manipulation protocol in patients with CD.

METHODS

The patients were referred by an otoneurologist, and after inclusion were randomly divided into a control group and an intervention group. The intervention was based on the application of a traction-manipulation protocol in the resting position. Dizziness intensity, self-reported disability, and cervical range of motion with and without a fixed gaze were assessed. All data were collected beforehand and at two days and four weeks after intervention.

RESULTS

At the two-days follow-up, statistically significant differences in favor of the intervention were observed between groups in the primary outcomes of dizziness intensity (p < .001) and Dizziness Handicap Inventory (p < .001), and at the four-week follow-up in dizziness intensity (p < .001) and Dizziness Handicap Inventory (p < .001).

CONCLUSIONS

The traction-manipulation protocol reduces the intensity of dizziness, the patient's self-perceived disability, and improves cervical mobility with and without fixed gaze.

Test - re-test reliability and concurrent validity of cervical active range of motion in young asymptomatic adults using a new inertial measurement unit device

OBJECTIVES

Cervical range of motion (CROM) is one of the first things evaluated in cervical disorders. DyCare-Lynx is an inertial measurement unit device that was recently designed to measure CROM. Therefore, the objectives of the present study were to test the reliability and validity of the DyCare-Lynx device for active CROM.

MATERIALS AND METHODS

This study included 36 healthy individuals for the reliability study and 31 individuals for the validity study. Test-retest reliability was examined in three different days, by the same examiner with a 4 ± 1-day interval between them in all cervical movements in random order. For validity, the CROM was tested with the Zebris Motion Analysis system and DyCare-Lynx simultaneously.

RESULTS

The interclass correlation coefficient (ICC) of the DyCare-Lynx ranged from 0.54 to 0.90. The standard error of measurement (SEM) ranged from 2.12°-7.65°. The smallest detectable change (SDD) ranged from 11.25% to 29.75%. The Pearson's r correlation of DyCare-Lynx with Zebris ranged from 0.655 to 0.957.

CONCLUSION

DyCare-Lynx showed moderate to excellent reliability and moderate-to-high validity. Moreover, SEM was low with acceptable SDD values for all movements. Overall, it can be suggested that DyCare-Lynx is a reliable and valid tool to evaluate active CROM.

Effects of occipital-atlas stabilization in the upper cervical spine kinematics: an in vitro study

This study compares upper cervical spine range of motion (ROM) in the three cardinal planes before and after occiput-atlas (C0–C1) stabilization. After the dissection of the superficial structures to the alar ligament and the fixation of C2, ten cryopreserved upper cervical columns were manually mobilized in the three cardinal planes of movement without and with a screw stabilization of C0–C1. Upper cervical ROM and mobilization force were measured using the Vicon motion capture system and a load cell respectively. The ROM without C0–C1 stabilization was 19.8° ± 5.2° in flexion and 14.3° ± 7.7° in extension. With stabilization, the ROM was 11.5° ± 4.3° and 6.6° ± 3.5°, respectively. The ROM without C0–C1 stabilization was 4.7° ± 2.3° in right lateral flexion and 5.6° ± 3.2° in left lateral flexion. With stabilization, the ROM was 2.3° ± 1.4° and 2.3° ± 1.2°, respectively. The ROM without C0–C1 stabilization was 33.9° ± 6.7° in right rotation and 28.0° ± 6.9° in left rotation. With stabilization, the ROM was 28.5° ± 7.0° and 23.7° ± 8.5° respectively. Stabilization of C0–C1 reduced the upper cervical ROM by 46.9% in the sagittal plane, 55.3% in the frontal plane, and 15.6% in the transverse plane. Also, the resistance to movement during upper cervical mobilization increased following C0–C1 stabilization.

A Two Joint Neck Model to Identify Malposition of the Head Relative to the Thorax

Neck pain is a frequent health complaint. Prolonged protracted malpositions of the head are associated with neck pain and headaches and could be prevented using biofeedback systems. A practical biofeedback system to detect malpositions should be realized with a simple measurement setup. To achieve this, a simple biomechanical model representing head orientation and translation relative to the thorax is introduced. To identify the parameters of this model, anthropometric data were acquired from eight healthy volunteers. In this work we determine (i) the accuracy of the proposed model when the neck length is known, (ii) the dependency of the neck length on the body height, and (iii) the impact of a wrong neck length on the models accuracy. The resulting model is able to describe the motion of the head with a maximum uncertainty of 5 mm only. To achieve this high accuracy the effective neck length must be known a priory. If however, this parameter is assumed to be a linear function of the palpable neck length, the measurement error increases. Still, the resulting accuracy can be sufficient to identify and monitor a protracted malposition of the head relative to the thorax.

Correlation and Reliability Analyses among the Upper Cervical Rotation-Flexion Test, Upper Cervical Flexion-Extension Test, and Upper Cervical Flexion Angle Measurement Using Radiography

(1) Background: The cervical rotation-flexion test is one method of measuring the range of motion of the upper cervical spine; however, this test has not been investigated in detail. The aim of this study was to investigate the reliability and concurrent validity of the upper cervical rotation-flexion test. (2) Methods: Twenty-five healthy individuals (13 women and 12 men) participated in this study. The participants underwent radiography, the upper cervical flexion-extension test, and the upper cervical rotation-flexion test in a sitting position while wearing a cervical goniometer to measure the upper cervical flexion angle. Three experienced physical therapists administered the upper cervical rotation-flexion test using the cervical device, twice for each participant. Inter-rater and intra-rater reliabilities were evaluated using the intraclass correlation coefficient (95% confidence interval). (3) Results: The inter-rater and intra-rater reliability values of the total scores were excellent. The results of the upper cervical rotation-flexion test significantly correlated with those of the radiographic evaluation of the upper cervical flexion angle (r = 0.80, p < 0.001) and those of the upper cervical flexion-extension test (r = 0.77, p < 0.001). Significant correlations among the three test results were observed. (4) Conclusions: The findings of this study suggest that the upper cervical rotation-flexion test is meaningful for independently measuring the upper cervical flexion angle.

On-site multi-component intervention to improve productivity and reduce the economic and personal burden of neck pain in Swiss office-workers (NEXpro): protocol for a cluster-randomized controlled trial

Background

Non-specific neck pain and headache are major economic and individual burden in office-workers. The aim of this study is to investigate the effect of a multi-component intervention combining workstation ergonomics, health promotion information group workshops, neck exercises, and an app to enhance intervention adherence to assess possible reductions in the economic and individual burden of prevalent and incident neck pain and headache in office workers.

Methods/design

This study is a stepped wedge cluster-randomized controlled trial. Eligible participants will be any office-worker aged 18–65 years from two Swiss organisations in the Cantons of Zurich and Aargau, working more than 25 h a week in predominantly sedentary office work and without serious health conditions of the neck. One hundred twenty voluntary participants will be assigned to 15 clusters which, at randomly selected time steps, switch from the control to the intervention group. The intervention will last 12 weeks and comprises workstation ergonomics, health promotion information group workshops, neck exercises and an adherence app. The primary outcome will be health-related productivity losses (presenteeism, absenteeism) using the Work Productivity and Activity Impairment Questionnaire. Secondary outcomes are neck disability and pain (measured by the Neck Disability Index, and muscle strength and endurance measures), headache (measured by the short-form headache impact test), psychosocial outcomes (e.g. job-stress index, Fear-Avoidance Beliefs Questionnaire), workplace outcomes (e.g. workstation ergonomics), adherence to intervention, and additional measures (e.g. care-seeking). Measurements will take place at baseline, 4 months, 8 months, and 12 months after commencement. Data will be analysed on an intention to treat basis and per protocol. Primary and secondary outcomes will be examined using linear mixed-effects models.

Discussion

To the authors’ knowledge, this study is the first that investigates the impact of a multi-component intervention combining current evidence of effective interventions with an adherence app to assess the potential benefits on productivity, prevalent and incident neck pain, and headache. The outcomes will impact the individual, their workplace, as well as private and public policy by offering evidence for treatment and prevention of neck pain and headache in office-workers.

Trial registration

ClinicalTrials.gov, NCT04169646. Registered 15 November 2019 - Retrospectively registered.

Joint position error after neck protraction-retraction movements in healthy office workers: a cross-sectional study

Since the upper cervical spine (UCS) has been regarded to be distinct from the lower cervical spine (LCS), joint position error (JPE) needs to be tested separately for both regions. The purpose of this study was to investigate the JPE after cervical protraction/retraction movements, involving opposite movements of extension and flexion for the UCS and LCS. These movements are frequently performed during office work. Cervical JPEs were tracked in thirty healthy office workers while performing four tests of cervical pro-retraction movements with variations in vision and movement direction, and assessed using the Kinect head tracker (Microsoft Corp), placed in front of each participant. The JPE was expressed in constant (CE), absolute (AE) and variable errors (VE). Multilevel linear models evaluated main and interaction effects of vision, movement direction, cervical region and sex. Slightly larger JPEs have been found in the UCS. Vision showed no effect on any outcome variable. No effect exceeded typical measurement errors reported for the Kinect head tracker. This study showed, that JPEs after pro-retraction movements of the head and neck may differ for UCS and LCS. The differences were small and not beyond measurement error reported for the Kinect.

Validity and reliability of two Smartphone applications to measure the lower and upper cervical spine range of motion in subjects with chronic cervical pain

BACKGROUND

Cervical pain is the biggest musculoskeletal health problem in industrialised countries. There is an important association between this and decrease in range of motion.

OBJECTIVE

Estimate the validity and reliability intra and inter examiner of two Smartphone apps regarding the measurement of lower and upper cervical spine range of motion in subjects with chronic cervical pain.

METHODS

A cross-sectional study was conducted. The sample consisted of 25 subjects with chronic cervical pain. An examiner made a measurement of the range of motion using the CROM device as a gold standard, afterwards, another examiner did the same using a Smartphone, in order to establish validity. After this, the Smartphone examiner and a new examiner simultaneously conducted the intra and inter examiner reliability.

RESULTS

Measurement of the lower and upper cervical spine range show an excellent validity (> 0.75), with an excellent intra and inter reliability (> 0.75) in all movements except flexion of upper cervical spine (0.75-0.65).

CONCLUSION

The two Smartphone applications used in this study showed an excellent validity compared to the CROM. The intra and inter reliability is excellent for all movements, except for the upper cervical spine flexion.

Concurrent validity and reliability of a mobile tracking technology to measure angular and linear movements of the neck

The neck can be moved in six degrees of freedom. Current 3D-optoelectronic motion-capture systems capable of measuring these movements are inappropriate for use in clinical practice because they are stationary, expensive and time-consuming. We therefore developed a less complex 3D-tracking technology based on Steam®VR to measure six degrees of freedom in a clinical setting. The aim of this study was to assess the validity and reliability of this system. The developed prototype consists of two infrared-emitting lighthouses and sensors, mounted on the participant's helmet and trunk belt, to detect the orientation of the head and trunk. The system was evaluated by means of an infrared light-reflecting marker tracking system. Twenty healthy participants, equipped with these sensors and markers, performed thirteen neck movement tasks. Linear and angular movements were measured. These tasks were repeated after six to eight days to assess test-retest reliability. Concurrent validity was assessed by the root mean square error, and reliability with generalizability theory. With an average root mean square error between 1.2 and 2.0° in angular and 0.4-0.5 cm in linear movements, the prototype was shown to precisely track these movements. Reliability of the prototype and the reference system was comparable for all tasks. A high contribution of participant's variability to the observed variance was generally detected, with the exception of joint repositioning error and upper cervical flexion. The reliability was task-specific and did not differ between the systems. The prototype system was shown to be valid, although the reliability of the repositioning and upper cervical flexion tests needs to be reconsidered.

CORRELATION BETWEEN CERVICAL MORPHOLOGY, PAIN, FUNCTIONALITY, AND ROM IN INDIVIDUALS WITH CERVICALGIA

ABSTRACT Objective: To verify if there is a correlation between the morphology of the cervical spine curvature, pain intensity, functional disability, and range of motion in individuals with cervicalgia. Methods: Thirty-nine individuals were evaluated using x-rays in the right sagittal plane (Cobb C1-C7 two-line method), visual analogue scale, Neck Disability Index questionnaire, and fleximeter. Descriptive statistical analysis (percentage, mean and standard deviation) and inferential (independent t-test and Pearson product-moment correlation coefficient, α=0.05) were performed. Results: There were significant correlations, ranging from moderate to high, between functional capacity and pain intensity (r=0.637, p<0.001), and total range of motion (r=-0.568, p<0.001), and extension (r=-0.610, p<0.001), and between pain intensity and range of motion (r=-0.422, p=0.007). Regarding the morphology of the cervical spine curvature, none of the variables showed a significant correlation. Conclusions: Cervical morphology, more specifically related to the curvature in the sagittal plane, does not seem to interfere alone with pain, functionality, and range of motion. In contrast, it is possible to affirm that higher levels of pain generate a smaller range of cervical movement, especially of extension, which, in turn, results in greater functional losses in individuals with neck pain. Level of Evidence II; Prognostic Studies - Investigating the Effect of a Patient Characteristic on the Outcome of Disease.

Short-term effects of the suboccipital muscle inhibition technique and cranio-cervical flexion exercise on hamstring flexibility, cranio-vertebral angle, and range of motion of the cervical spine in subjects with neck pain: A randomized controlled trial

BACKGROUND

Cervical spinal instability often leads to neck pain and forward head posture (FHP). To improve neck pain and FHP, both the suboccipital muscle inhibition (SMI) technique and cranio-cervical flexion exercise (CCFE) have been used. However, little is known regarding the validity of hamstring flexibility in neck pain subjects after CCFE as a treatment index, and comparison between the SMI technique and CCFE for neck pain treatment.

OBJECTIVE

This study aimed to determine the short-term effects of SMI technique and CCFE, which represent passive and active exercise programs, respectively, and whether these improve the straight leg raise (SLR) test results, popliteal angle (PA), cranio-vertebral angle (CVA), and cervical range of motion (CROM) and are equally effective in immediate enhancement of such measures in neck pain subjects.

METHODS

Twenty subjects with neck pain were randomly allocated to the SMI and CCFE groups (n= 10 each). The outcomes were evaluated via clinical evaluation and SLR, PA, CVA, and CROM measurement before and after intervention.

RESULTS

SLR test results, PA, CVA (sitting and standing), and CROM (flexion, extension, lateral flexion, and right and left rotations) after both interventions were significantly higher than those before the interventions (P< 0.05). The SLR test results (left), PA, and CVA (standing) after the SMI technique improved to levels similar to those observed after CCFE.

CONCLUSIONS

Both the SMI technique and CCFE improve SLR test results, PA, CVA, and CROM and are equally effective in immediate enhancement of the hamstring flexibility, CVA, and CROM in subjects with neck pain.

Experimental assessment of cervical ranges of motion and compensatory strategies

Background

Literature is still limited regarding reports of non-invasive assessment of the cervical range of motion in normal subjects. Investigations into compensatory motions, defined as the contribution of an additional direction to the required motion, are also limited.

The objectives of this work were to develop and assess a reliable method for measuring the cervical range of motion in order to investigate motion and compensatory strategies.

Methods and data collection

Ninety-seven no neck-related pain subjects (no severe cervical pathology, 57 women, age: 28.3 ± 7.5y. old, BMI: 22.5 ± 3.2 kg/m²) underwent a non-invasive cervical range of motion assessment protocol. In-vivo head’s motion relative to the thorax was assessed through the measurement of the main angular amplitudes in the 3 directions (flexion/extension, axial rotations and lateral inclinations) and associated compensatory motions using an opto-electronic acquisition system.

Results

The principal motion reproducibility resulted in intra-class correlation coefficients ranging from 0.81 to 0.86. The following maximum ranges of motion were found: 127.4 ± 15.1° of flexion/extension, 89.3 ± 12° of lateral inclinations and 146.4 ± 13° of axial rotations after 6 outlier exclusions. Compensatory motions highly depend on the associated principal motion: for flexion/extension: (3.5 ± 7.6;-2.1 ± 7.8°), for rotation: (25.7 ± 17.9°;0.4 ± 4.7)°, for inclination: (22.9 ± 34.7°;-0.04 ± 8.7°). Age, BMI and weight significantly correlated with flexions (p < 0.032). Motion patterns were identified through clustering.

Conclusions

This kinematic analysis has been proven to be a reliable diagnostic tool for the cervical range of motion. The non-unicity and variability of motion patterns through the clustering of motion strategy identification have been shown. Compensatory motions contributed to such motion pattern definition despite presenting significant intra-individual variability.

Reliability of Smartphone Inclinometry to Measure Upper Cervical Range of Motion

Context: Assessment of upper cervical range of motion (UCROM) and mobility is commonly performed in the clinical setting for patients suffering from headache, neck pain, and vestibular dysfunction. Reliable and reproducible measurement of this motion is often difficult or too expensive to perform in the clinical setting. Smartphone applications using the device’s internal gyroscope offer an easy and inexpensive means of measuring UCROM, but their reliability has not been reported in the literature. Objective: To assess the reliability of an inclinometer application installed on 2 different devices (iPhone 6 [IP] and android [AN]) and to measure UCROM in a healthy population. Design: Two examiners assessed passive UCROM. Each examiner was assigned to a specific smartphone, and a repeated-measures design consisting of 3 trials for each examiner–phone was performed. The order of testing was randomized, and the examiners were blinded to UCROM measures. Setting: Laboratory. Participants: A total of 38 subjects (19 females and 19 males; age: 23.8 [1.2] y) without pain or injury to the neck or spine for at least 3 months. Intervention: Each examiner passively flexed the head fully, rotated the head fully in 1 direction, and then in another. Peak rotation measures were recorded from each smartphone. Three trials were performed for each phone, with a 2-minute break between examiners/phones. Main Outcome Measures: Intraclass correlation coefficient using a 2-way mixed, absolute agreement model was obtained (1) between each examiner–phone and (2) within each examiner–phone for the measurements in each rotation direction. Results: Interphone/examiner reliability comparing average peak and total UCROM for each device was excellent (.87, .81). Intraphone/examiner reliability, determined across 3 trials, was also excellent (AN right rot. = .91, AN left rot. = .96; IP right rot. = .98, IP left rot. = .95). Conclusion: UCROM can be reliably measured using a smartphone inclinometer application.

The C0-C2 axial rotation test: normal values, intra- and inter-rater reliability and correlation with the flexion rotation test in normal subjects

OBJECTIVES

Impairment in upper cervical spine mobility is associated with cervicogenic headache severity and disability. Measures of such mobility include the flexion-rotation test (FRT), which requires full cervical flexion and may be influenced by lower cervical spine dysfunction. The C0-C2 axial rotation test also evaluates upper cervical mobility but normal values and reliability have not been reported. Our objective is to determine normal values, and intra-rater and inter-rater reliability of the C0-C2 axial rotation test.

METHODS

Two therapists independently evaluated the FRT and C0-C2 axial rotation test with an iPhone compass application on 32 asymptomatic subjects with mean age 40.53 (SD 11.64) years on two occasions. Measurement procedures were standardized; and order of testing randomized.

RESULTS

For the FRT and C0-C2 axial rotation test reliability was high (ICC > 0.88). For rater one, Mean range to the left during the FRT and C0-C2 axial rotation test was 45.0° (6.04) and 14.43° (2.94), respectively, while range to the right was 44.6° (6.57) and 15.44° (2.68). For the FRT and C0-C2 axial rotation test the standard error of measurement was at most 2°, while the minimum detectable change was at most 4°. A strong positive correlation exists between the FRT and C0-C2 axial rotation test (r = 0.84, P < 0.01).

DISCUSSION

The range recorded during the C0-C2 axial rotation test and FRT have high levels of reliability when evaluated using an iPhone. The strong correlation between the FRT and C0-C2 axial rotation test indicate that both may be measuring similar constructs, but each test needs to be referenced to normal values.

Comparative analysis of head-tilt and forward head position during laptop use between females with postural induced headache and healthy controls

OBJECTIVES

To compare 1) maximum manually induced head-protraction, head-tilt and forward head position and 2) the evolution of head-tilt and forward head position during a laptop-task between a headache- and control-group.

METHODS

Angles for maximum head-protraction, head-tilt and forward head position of 12 female students with postural induced headache and 12 female healthy controls were calculated at baseline and while performing a laptop-task.

RESULTS

The headache-group demonstrated an increased passive head-protraction of 22.30% compared to the control-group. The ratio of forward head position during habitual sitting to the maximum head-protraction differed significantly (p = 0.046) between headache-group (1.4 ± 0.4) and the control-group (1.1 ± 0.2). The headache-group showed a biphasic forward head position and head-tilt profile. These profiles differed significantly (p < 0.05) between groups and were negatively correlated (rE = -0.927).

CONCLUSION

The headache-group showed a larger passive head-protraction with a habitual forward head-position further located from the end-range. During the laptop-task forward head position and head-tilt behaved biphasically with a more static forward head position and a more dynamic head-tilt.