Measurement Properties of the Craniocervical Flexion Test: A Systematic Review

Machine learning models for classifying non-specific neck pain using craniocervical posture and movement

OBJECTIVE

Physical therapists and clinicians commonly confirm craniocervical posture (CCP), cervical retraction, and craniocervical flexion as screening tests because they contribute to non-specific neck pain (NSNP). We compared the predictive performance of statistical machine learning (ML) models for classifying individuals with and without NSNP using datasets containing CCP and cervical kinematics during pro- and retraction (CKdPR).

DESIGN

Exploratory, cross-sectional design.

SETTING AND PARTICIPANTS

In total, 773 public service office workers (PSOWs) were screened for eligibility (NSNP, 441; without NSNP, 332).

METHODS

We set up five datasets (CCP, cervical kinematics during the protraction, cervical kinematics during the retraction, CKdPR and combination of the CCP and CKdPR). Four ML algorithms-random forest, logistic regression, Extreme Gradient boosting, and support vector machine-were trained.

MAIN OUTCOME MEASURES

Model performance were assessed using area under the curve (AUC), accuracy, precision, recall and F1-score. To interpret the predictions, we used Feature permutation importance and SHapley Additive explanation values.

RESULTS

The random forest model in the CKdPR dataset classified PSOWs with and without NSNP and achieved the best AUC among the five datasets using the test data (AUC, 0.892 [good]; F1, 0.832). The random forest model in the CCP dataset had the worst AUC among the five datasets using the test data [AUC, 0.738 (fair); F1, 0.715].

CONCLUSION

ML performance was higher for the CKdPR dataset than for the CCP dataset, suggesting that ML algorithms are more suitable than classical statistical methods for developing robust models for classifying PSOWs with and without NSNP.

Randomised controlled trial assessing the effects of 6-week telerehabilitation exercise programme on chronic non-specific neck pain: a study protocol

Chronic non-specific neck pain is one of the most common musculoskeletal conditions affecting the work and lifestyle of those suffering from it. Physiotherapy interventions, such as strength training and stretching, have positively influenced neck pain. Patient adherence to home-based exercises is a growing concern that could be easily improved through telerehabilitation exercise programmes. This can also be a cost-effective, time-efficient and patient-suitable service. Therefore, this study aims to establish the effectiveness of telerehabilitation exercise intervention by measuring patient adherence, pain score, disability index, cervical range of motion (CROM) and cervical muscle endurance. This randomised controlled trial will include n=60 participants, aged 18-45 years, in a 6-week home-based exercise programme delivered through telerehabilitation or paper-based instructions. Outcome measures from participants will be obtained at baseline and on completion of 6 weeks. These will include the Visual Analogue Scale for Pain, Neck Disability Index questionnaire, CROM by using the CROM instrument and cervical muscle endurance through the Craniocervical Flexion Test. For baseline differences between groups, an independent samples t-test will be used. Repeated measures analysis of variance will be used for within-group and between-group analyses at three different time points (0 weeks, 3 weeks, 6 weeks). Trial registration number:NCT06076174.

Reliability and measurement error of sensorimotor tests in patients with neck pain: a systematic review

BACKGROUND

Neck pain is one of the leading causes of years lived with disability, and approximately half of people with neck pain experience recurrent episodes. Deficits in the sensorimotor system can persist even after pain relief, which may contribute to the chronic course of neck pain in some patients. Evaluation of sensorimotor capacities in patients with neck pain is therefore important. No consensus exists on how sensorimotor capacities of the neck should be assessed in physiotherapy. The aims of this systematic review are: (a) to provide an overview of tests used in physiotherapy for assessment of sensorimotor capacities in patients with neck pain; and (b) to provide information about reliability and measurement error of these tests, to enable physiotherapists to select appropriate tests.

METHODS

Medline, CINAHL, Embase and PsycINFO databases were searched for studies reporting data on the reliability and/or measurement error of sensorimotor tests in patients with neck pain. The results for reliability and measurement error were compared against the criteria for good measurement properties. The quality of evidence was assessed according to the modified GRADE method proposed by the COSMIN group.

RESULTS

A total of 206 tests for assessment of sensorimotor capacities of the neck were identified and categorized into 18 groups of tests. The included tests did not cover all aspects of the sensorimotor system; tests for the sensory and motor components were identified, but not for the central integration component. Furthermore, no data were found on reliability or measurement error for some tests that are used in practice, such as movement control tests, which apply to the motor component. Approximately half of the tests showed good reliability, and 12 were rated as having good (+) reliability. However, tests that evaluated complex movements, which are more difficult to standardize, were less reliable. Measurement error could not be evaluated because the minimal clinically important change was not available for all tests.

CONCLUSION

Overall, the quality of evidence is not yet high enough to enable clear recommendations about which tests to use to assess the sensorimotor capacities of the neck.

Fat Infiltration of Multifidus Muscle Is Correlated with Neck Disability in Patients with Non-Specific Chronic Neck Pain

Background: Chronic non-specific neck pain (CINP) is common, but the etiology remains unclear. This study aimed to examine the relationship between cervical muscle composition (cervical multifidus and longus capitis/longus colli), morphometry, range of movement, muscle function, and disability severity (Neck Disability Index) in patients with CINP. Methods: From September 2020 to July 2021, subjects underwent cervical MRI and clinical tests (cervical range of motion, cranio-cervical flexion test, neck flexor, and extensor muscle endurance). MRI analysis comprised muscle cross-sectional area, volume, and fat infiltration of multifidus and longus colli between C4 and C7 levels. Results: Twenty-five participants were included. Multiple linear regression analysis indicated that NDI was positively correlated with the volume percentage of fat infiltration of the multifidus (B = 0.496), negatively correlated with fat-free muscle volume of the multifidus normalized by subject height (B = −0.230), and accounted for 32% of the variance. There was no relationship between neck disability and longus capitis/longus colli morphology. We also found no relationship between neck disability scores, neck flexor or extensor muscle endurance, or the outcome motor control test of craniocervical flexion (p > 0.05). Conclusions: Neck disability was moderately correlated with the percentage of fat volume in the multifidus muscle and fat-free volume of the multifidus. There was no relationship between NDI scores and muscle function test outcomes or any fat or volume measures pertaining to the longus colli muscle.

Reliability, Validity, and Responsiveness of the Craniocervical Flexion Test in People Who Are Asymptomatic and Patients With Nonspecific Neck Pain: A Systematic Review and Meta-Analysis

OBJECTIVE

Among the tests designed to evaluate neck neuromuscular function, the craniocervical flexion test (CCFT) assesses the function of the deep cervical flexor muscles (DCFs). The purpose of this study was to conduct a review and meta-analysis of published articles about all measurement properties of the different CCFT versions (CCFT Activation Score [CCFT-AS], CCFT Performance Index [CCFT-PI], CCFT Cumulative Performance Index [CCFT-CPI], and CCFT alternative procedures for measuring activation level (CCFT1) or endurance (CCFT2) in people who were asymptomatic and people with nonspecific neck pain.

METHODS

PubMed Central, MEDLINE, CINAHL, Scopus, Web of Science, and Google Scholar were searched from inception to June 30, 2020. Studies were selected if they reported data on reliability, validity, and/or responsiveness of the CCFT in adults who were asymptomatic or who had nonspecific neck pain. Two reviewers independently selected the studies, conducted quality assessment, and extracted the results. All meta-analyses used a random-effects model.

RESULTS

Twenty-one studies met the inclusion criteria. The rating of interrater reliability (assessed for CCFT-AS and CCFT-CPI) was positive only for using the test at a group level. The same rating was ascribed to the intrarater reliability of CCFT-AS, CCFT1, and CCFT2, whereas CCFT-PI and CCFT-CPI showed positive intrarater reliability for assessment of individuals as well. CCFT validity was rated as positive for expressly assessing DCF action when measuring DCF activation through electromyography-not through ultrasonography-or craniocervical flexion motion as well as for differentiating patients who were asymptomatic and patients who had nonspecific neck pain (only the AS version). CCFT validity was rated as negative for investigating the CCFT performance correlation with the severity of nonspecific neck pain. CCFT responsiveness was rated as negative.

CONCLUSIONS

The CCFT is a potentially useful tool for detecting impairment in DCF control and identifying patients who have nonspecific neck pain and who would benefit from a targeted intervention. However, the limited reliability affects its suitability for that purpose. Further research on the reliability of different CCFT versions in which the raters are thoroughly trained is strongly recommended.

IMPACT

The CCFT might help to detect impairment in DCF control and identify patients who have nonspecific neck pain and who would benefit from a targeted intervention. However, the poor reliability of most versions of the test greatly limits its application in clinical practice. Only CCFT-PI and CCFT-CPI seem reliable enough to help in clinical decision-making at the individual level.

Effects of breathing re-education on endurance, strength of deep neck flexors and pulmonary function in patients with chronic neck pain: A randomised controlled trial

Background

People with chronic neck pain show decreased endurance and strength of cervical muscles with compromised respiratory function. There is little evidence that improvement in breathing function of people with neck pain can help in enhancing cervical muscle strength and pulmonary function. The objective of this our clinical trial was to examine the effects of breathing re-education combined with physiotherapy on endurance and strength of deep neck flexors, and pulmonary function in patients with chronic neck pain.

Methods/design

In this double blind randomised clinical trial, 30 patients with chronic neck pain (25–50 years old) were randomly allocated to two groups. Group A, physiotherapy (n = 15), and Group B, breathing re-education (n = 15). The duration of intervention was eight weeks with treatment five days a week. The endurance was measured with the craniocervical flexion test, strength with a handheld dynamometer (Baseline USA) and pulmonary functions with the Spiro lab 4 (USA) at baseline, at week four and at week eight of the intervention.

Discussion

There was a significant between group improvement in the strength of deep neck flexors and forced vital capacity (FVC) in Group B p = 0.0001 and p = 0.0200 (p ˂ 0.05) respectively. Intergroup comparisons showed no significant differences for endurance, cervical extensor strength, Forced Expiratory Volume in one second (FEV1), and FEV1/FVC percentage.

Conclusion

Our study concluded that breathing re-education combined with other physiotherapy management is effective for improving the strength of neck flexors and increasing FVC in people with chronic neck pain.

Clinical implication

Breathing re-education may be part of physiotherapy management in patients with chronic neck pain.

Trial Registration

Iranian Registry of Clinical Trials, IRCT20200226046623N1, https://www.irct.ir/trial/46240.

The Effect of Adding Dry Needling to Physical Therapy in the Treatment of Cervicogenic Headache: A Randomized Controlled Trial

OBJECTIVE

To compare the long-term effect of adding real or sham dry needling with conventional physiotherapy in cervicogenic headache.

DESIGN

A randomized controlled trial.

SETTING

Physiotherapy Clinic, Rouhani Hospital of Babol University of Medical Sciences, Iran.

SUBJECTS

Sixty-nine patients with cervicogenic headache.

METHODS

Patients were randomly assigned into a control group (n = 23) receiving conventional physical therapy; a dry needling group (n = 23) receiving conventional physical therapy and dry needling on the cervical muscles; placebo needling group (n = 23) receiving conventional physical therapy and superficial dry needling at a point away from the trigger point. The primary outcome was the headache intensity and frequency. Neck disability, deep cervical flexor performance and range of motion were secondary outcomes. Outcomes were assessed immediately after treatment and one, three and six months later.

RESULTS

Sixty-five patients were finally included in the analysis. Headache intensity and neck disability decreased significantly more in the dry needling compared to sham and control groups after treatment and during all follow-ups. The frequency of headaches also reduced more in the dry needling than in control and sham groups, but it did not reach statistical significance. Higher cervical range of motion and enhancement of deep cervical flexors performance was also observed in the dry needling compared to sham and control groups.

CONCLUSION

Dry needling has a positive effect on pain and disability reduction, cervical range of motion and deep cervical flexor muscles performance in patients with cervicogenic headache and active trigger points, although the clinical relevance of the results was small.

Craniocervical flexion test in patients with migraine: Discriminative validity and accuracy

OBJECTIVES

To evaluate the discriminative validity and provide a clinical cut-off of the craniocervical flexion test (CCFT) in migraineurs stratified by the report of neck pain, headache-related disability and neck disability.

METHODS

Fifty women without headache and 102 women with migraine were recruited by convenience from a local tertiary care setting. Migraine diagnosis followed the International Classification of Headache Disorders. All volunteers underwent the CCFT. Patients with migraine answered the Migraine Disability Assessment (MIDAS) and Neck Disability Index (NDI) questionnaires. Discriminative validity was verified by group comparison, and the clinical cut-off was obtained and classified according to the diagnostic accuracy of the CCFT.

RESULTS

The CCFT presented discriminative validity for comparing control (median = 28, IQR = 6) with migraine (median = 26, IQR = 4, P = .01) and migraine with neck pain (median = 26, IQR = 4, P = .01), but not among the migraine subtypes with disability by migraine or neck pain-related disability on the MIDAS and NDI. The diagnostic accuracies were classified between poor and not discriminating with the area under the receiver operating characteristic curve ranging from 57% to 69% and non-acceptable values of sensitivity, specificity and positive and negative likelihood ratios.

CONCLUSION

The CCFT can discriminate asymptomatic controls from migraine patients with and without neck pain. However, it cannot discriminate patients with migraine according to their pain-related disability. Also, the CCFT does not offer an optimal cut-off value in migraine patients adequate to clinical practice.

Craniocervical flexion performance in computer users: An observational study

Study aim: To compare the performance of deep cervical flexors (DCF) among computer users (CU) and non-users using the craniocervical flexion test (CCFT).

Material and methods: Eighty nine computer users and 100 non-users were recruited for evaluation of their craniocervical muscle performance. The activation score and performance index were assessed using the CCFT. Comparison of craniocervical flexor performance between the two groups was evaluated using the Mann Whitney test. A Chi-Square test was used to test the association between age, years of work and craniocervical flexion. Significance was set at p ≤ 0.05.

Results: The median activation score was lower among computer users (median pressure-24 mmHg as compared to non-users (median pressure-28 mmHg) (p < 0.01). The performance index among computer users was lower when compared to non-users. Also, age (p < 0.001) and the years of work experience (p = 0.006) were associated with the DCF performance.

Conclusion: CU have lower activation and endurance of the DCF compared to non-users. The endurance of the DCF was associated with the age and years of computer usage.

Are there gender differences in neck pain and musculoskeletal disorders of the cervical spine associated with migraine?

OBJECTIVE

To evaluate gender differences in clinical characteristics of migraine by examining presence and severity of cutaneous allodynia, migraine-related disability, neck pain and its associated disability, passive mobility of the upper cervical spine, and performance of the deep neck flexor muscles.

DESIGN

cross-sectional study.

SUBJECTS

30 men and 30 women with migraine.

METHODS

Participants responded to the questionnaires Migraine Disability Assessment questionnaire, 12-item Allodynia Symptom Checklist and Neck Disability Index. The mobility of the upper cervical spine was assessed by using the Flexion-Rotation Test. Performance of the deep neck flexor muscles was evaluated by applying the Craniocervical Flexion Test. Comparison of the groups was carried out by using the Student's t-test or the chi-square test. The prevalence ratio was also calculated.

RESULTS

Women showed a higher prevalence of cutaneous allodynia (p = 0.001) and a 4 times greater risk of having severe cutaneous allodynia than to men (p = 0.007). No gender differences were observed in migraine-related disability (p = 0.08). Women showed higher prevalence of self-reported neck pain (p = 0.03) and increased risk of having this symptom in comparison to men (Prevalence Ratio=1.69; p = 0.025). However, there were no gender differences in neck pain-related disability (p = 0.25), mobility of the upper cervical spine (p = 0.92), or performance of the deep neck flexor muscles (p = 0.52).

CONCLUSION

Women with migraine had a higher frequency of self-reported neck pain and higher prevalence and severity of cutaneous allodynia when compared to men. However, the two groups did not differ regarding neck pain-related disability and performance in the physical tests.

Does focus of attention alter craniocervical flexion test motor learning? A randomized controlled trial

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.