Isometric endurance test of the cervical flexor muscles – Reliability and normative reference values

Cervical muscle parameters and allodynia in migraine and cervical pain-A controlled study

BACKGROUND

Neck pain is common among individuals with migraine, but there is a lack of information of how this comorbidity can be associated with cervical muscle function. This controlled cross-sectional study aimed to compare cervical muscle function, activity, and sensitization in women with migraine, neck pain, both, and neither.

METHODS

This study included women, between 18 and 55 years old, with either episodic migraine with or without aura, without any concomitant headache diagnosis; chronic neck pain, with at least moderate intensity and mild disability; or neither headache nor neck pain. Pain pressure threshold, allodynia, muscle strength, and endurance and cervical muscles activity were evaluated.

RESULTS

One hundred subjects, with mean age of 30.4 years old, were stratified by diagnosis (n = 25 per group) and by self-reported pain during tests. Lower endurance during flexion was observed for migraine and neck pain (34s) relative to neck pain alone (45s), migraine (40s), and controls (58s) (p = 0.04). For extensor endurance, means were 142s, 166s, 215s, and 270s, respectively (p < 0.001). Endurance times were impacted by the presence of test-induced pain decreasing about 40%-53% of the performance. Diagnostic groups did not differ significantly in strength (p > 0.05), but all pain groups presented significantly higher proportion of test-induced pain, lower muscle activity during the maximal isometric voluntary contractions, and lower pressure pain thresholds.

CONCLUSION

Patients with migraine, chronic neck pain, and the association of both present altered cervical muscle function and activity. Also, test-induced pain impacts significantly on neck muscles endurance.

SIGNIFICANCE

The diagnosis of migraine and chronic neck pain is associated with altered function and activity of the cervical muscles. However, the test-induced pain had an important contribution to worse cervical muscle endurance. This suggests that the therapeutic approach should focus on de-sensitization of the trigeminal-cervical complex when dealing with the comorbidity of migraine and cervical pain.

A new visual feedback-based system for the assessment of pinch force, endurance, accuracy and precision. A test-retest reliability study

Introduction

Given that pinch is a precision grip involved in sustained submaximal activities, a Sustained Contraction (SC) task could be associated to Maximal Voluntary Contraction (MVC). To better evaluate the thumb-index system, the test-retest reliability of pinch MVC and SC, measured by a visual feedback-based pinch gauge was assessed.

Methods

26 healthy participants performed MVC and SC in two separate sessions. SC required to maintain 40%MVC as long as possible and it was evaluated in terms of time, accuracy (Mean Distance between force trace and target force, MD), precision (Coefficient of Variability of force trace, CV). MD and CV analyses were conducted dividing the SC task into three equivalent time stages (beginning, middle, exhaustion). Relative Reliability (RR) was measured by Intraclass Correlation Coefficient, and Absolute Reliability (AR) was measured by Standard Error of Measurement and by Bland-Altman plot.

Results

MVC and Time showed high RR and AR in both hands. RR of MD and CV in right hand was excellent in the beginning and middle stages, and fair in the exhaustion one, showing decreasing reliability as fatigue increases. In the left hand RR of MD and CV was generally lower. MD showed excellent reliability in the beginning stage and good reliability in the other stages. CV showed fair relative reliability at both beginning and middle stages, excellent in the last one. Conversely, it was observed high AR of MD and CV in all stages in both hands.

Conclusions

All indices are reliable to assess motor control of thumb-index pinch in both hands.

Concurrent Validity and Reliability of a Low-Cost Dynamometer to Assess Maximal Isometric Strength in Neck Movements

OBJECTIVE

This study aimed to evaluate the concurrent validity and reliability of a low-cost digital dynamometer to assess maximal isometric strength in neck movements.

METHODS

Twelve recreationally active participants (6 women, 6 men; age: 24.1 ± 3.4 years; height: 1.71 ± 0.06 m; weight: 64.6 ± 11.7 kg) performed neck flexion, extension, and lateral flexion, and maximal isometric strength was simultaneously measured using an isokinetic dynamometer (gold standard) and a digital dynamometer to evaluate the concurrent validity of the latter. One week later, all the participants repeated 3 trials of each neck movement (3 minutes apart) registered only with the digital dynamometer. The first and second trial were guided by tester 1 and the third trial was guided by tester 2.

RESULTS

The concurrent validity of the digital dynamometer showed a nearly perfect correlation between both devices (r > 0.986, P < .001), with Bland-Altman plots showing absolute agreement. Intertester and intratester reliability were nearly perfect for all neck movements (intraclass correlation coefficient > 0.86).

CONCLUSION

The low-cost digital dynamometer showed valid and reliable measurements of maximal isometric strength in neck movements.

Reliability and Validity of Clinical Tests for Measuring Strength or Endurance of Cervical Muscles: A Systematic Review and Meta-analysis

OBJECTIVE

To evaluate the reliability and validity of clinical tests for measuring cervical muscle strength or endurance in participants with and without neck pain.

DATA SOURCE

Systematic review and meta-analysis on reliability and validity. Literature search was conducted on January 28, 2020, using 5 databases: MEDLINE, Cumulative Index to Nursing and Allied Health, EMBASE, SPORTDiscus, and Scopus.

STUDY SELECTION

We included studies that investigated the reliability or validity of clinical tests for measuring cervical muscle strength or endurance in participants with nonspecific chronic neck pain, with or without irradiation, or healthy participants. We included only those that were viable for daily practice and of low cost.

DATA EXTRACTION

Data were extracted as follows: (1) author and year of publication, (2) demographic values and health condition, (3) reported clinical tests, (4) inclusion and exclusion criteria, (5) description of test, (6) interrater reliability, and (7) intrarater reliability. For validity studies we also extracted the (8) reference method and (9) validity estimates.

DATA SYNTHESIS

Methodological quality was assessed with the Quality Appraisal of Diagnostic Reliability and the Guidelines for Reporting Reliability and Agreement Studies. Data on reliability and validity were extracted from included articles and then analyzed.

RESULTS

Thirty-one studies were included. Cervical flexor and extensor endurance test, craniocervical flexion test (CCFT), AND cervical muscle strength using a handheld dynamometer (HHD) showed moderate to good intra- and interrater reliability (intraclass correlation coefficients ranging from 0.64-0.90). Concurrent validity was measured by only 2 studies, which do not provide adequate evidence for a recommendation.

CONCLUSIONS

The cervical flexor and extensor endurance tests, CCFT, and HHD for measuring cervical strength presented an acceptable interrater and intrarater reliability.

Cervical Muscular Endurance Performance in Women With and Without Migraine

BACKGROUND

Despite previous evidence, the association between migraines and cervical muscular performance is unclear.

OBJECTIVE

To compare the differences in neck flexor and extensor muscle endurance between women with and without migraine.

METHODS

In this cross-sectional, controlled laboratory study, 26 women with migraine and 26 age-matched women without migraine or headache were assessed using clinical tests of neck flexor and extensor muscle endurance. Holding times were compared between groups using the Mann-Whitney U test for independent samples.

RESULTS

Patients with migraine exhibited a lower holding time for both neck extensor endurance (P = .001) and neck flexor endurance (P<.001) than did the controls. The median neck flexor holding time was 35.0 seconds for the migraine group and 60.5 seconds for the control group. The migraine group held the neck extensor endurance test position for a median of 166.5 seconds compared to 290.5 seconds held by the control group. Both groups reported a similar level of neck pain during the endurance tests (P>.05); however, only individuals in the migraine group reported pain referred to the head during testing.

CONCLUSION

Women with migraine demonstrated decreased neck flexor and extensor endurance compared to women without migraine, which may indicate an association between migraine and reduced performance of the neck muscles. J Orthop Sports Phys Ther 2019;49(5):330-336. Epub 26 Mar 2019. doi:10.2519/jospt.2019.8816.