Predicting the outcome of the greater occipital nerve block - an observational study on migraine patients with and without musculoskeletal cervical impairment

Ultrasound-Guided Combined Greater Occipital Nerve Block at the C2 Level with Trapezius Trigger Point Injection and Supraorbital-Supratrochlear Nerve Block: More Effective on Allodynia and Disability in Chronic Migraine

Background

Chronic migraine (CM) patients with cutaneous allodynia (CA) show a poor response to treatment. Long-term studies have yet to be conducted to demonstrate the efficacy of blocks on CA. This study evaluated the improvement in allodynia and disability in CM treated with ultrasound (US)-guided blocks.

Methods

In this prospective, non-randomized comparative study, 60 CM patients with CA were evaluated for the clinical effectiveness of the therapy using the numeric rating scale (NRS), headache impact test-6 (HIT-6), brush allodynia test, and allodynia symptom checklist (ASC-12). At the first visit, tenderness in the nerve or trapezius muscle was confirmed in the intervention group. US-guided greater occipital nerve block (GONB), GONB, and trapezius muscle injection (TPI), or GONB, TPI, and peripheral trigeminal nerve block (PTNB), respectively, were performed four times once a week for a month. Initial and third-month assessments were performed.

Results

The ASC-12 scores decreased in the GONB+TPI+PTNB and GONB groups more than the GONB+TPI group (mean rank, respectively, 26.86, 27.40, 38.39; P = 0.018). The decrease in HIT-6 scores was greater in the GONB+TPI+PTNB group than in the GONB group (mean rank, respectively, 21.98, 39.95, P < 0.017) in the first month. In the third month, the GONB+TPI+PTNB group scored HIT-6 significantly lower than GONB and GONB+TPI (mean rank: 18.84, 38.73, 35.61; P < 0.001).

Conclusions

GONB+TPI+PTNB was more successful in alleviating allodynia and disability.

Profiling migraine patients according to clinical and psychophysical characteristics: a cluster analysis approach

AIM

This study aims to profile migraine patients according clinical and psychophysical characteristics.

METHOD

In this observational study, two cohorts of migraine patients(episodic/chronic) were included. Cohort-1: ictal/perictal phase; Cohort-2: interictal phase.The following variables were assessed: headache frequency; disability; cervical active range of motion(AROM) in flexion, extension, right/left lateral flexion, right/left rotation; pressure-pain threshold(PPT) over: temporalis, two cervical areas(C1/C4 vertebral segments), and two distal pain-free areas(hand/leg). Cluster analysis was performed using the K-means algorithm. Differences across clusters were investigated.

RESULTS

Cohort-1: 100 patients were included, and two clusters were identified. Cluster-1.1 (19%), Cluster-1.2 (81%). Cluster 1.1 had a higher percentage of men (P = .037) and higher disability (P = .003) compared to Clusters 1.2. Cluster 1.2 had reduced AROM in flexion, extension, and left/right lateral flexion (P < .037), and lower PPT value in all areas (P < .001) compared to Cluster 1.1. Cohort-2: 98 patients were included and three clusters were identified. Cluster-2.1(18%), Cluster-2.2(45%), and Cluster-2.3(37%). Cluster-2.1 had a higher percentage of men compared to clusters-2.2 and 2.3 (P = .009). Cluster-2.3 had higher headache frequency, and disability compared to Cluster-2.2 (P < .006), and higher disability compared to Cluster-2.1 (P = .010). Cluster-2.3 had reduced AROM in all directions compared to Clusters-2.1 and 2.2 (P < .029). Clusters-2.2 and 2.3 have lower PPT values in all areas compared to Cluster-1.1 (P < .001).

CONCLUSION

In the Ictal/perictal phase, two clusters were identified according to clinical and psychophysical characteristics, with one group showing no psychophysical impairment and one with increased pain-sensitivity and cervical musculoskeletal-dysfunctions.In the interictal phase, three clusters could be identified, with one group showing no psychophysical impairment, one increased pain-sensitivity, and one increased pain sensitivity and cervical musculoskeletal-dysfunctions.

Musculoskeletal dysfunctions and physiotherapy treatment strategies in patients with migraine

BACKGROUND

Neck pain is prevalent in patients with migraine but its role for the physiotherapy management is unclear.

METHOD

In this narrative review, results of studies, contributing to the overall understanding of musculoskeletal dysfunctions in patients with migraine are summarized, as are approaches to subgroup migraine and attempts to improve migraine non-pharmacologically.

RESULTS

Our line of research shows that musculoskeletal dysfunctions are prevalent in patients with migraine. Pain provocation during manual palpation of the upper cervical spine might be relevant when referred pain to the head is elicited. This subgroup of patients might benefit from physiotherapy treatment to the neck. Preliminary data from treatment studies shows that a small reduction of headache and migraine days can be achieved when treating the neck. The reduction in migraine days might be enhanced when treating migraine as a chronic pain disease and adding pain neuroscience education to the neck treatment.

CONCLUSIONS

Physiotherapy assessment and treatment plays a role in the management of migraine. The effectiveness of different physiotherapy approaches and pain neuroscience education needs to be evaluated further in randomized controlled trials.

Cervical musculoskeletal impairments and pain sensitivity in migraine patients

INTRODUCTION

Currently, examination of migraine patients relies on a clinical interview investigating symptoms characteristics. Despite this, to help identify distinct migraine subtypes and allow a personalized treatment approach, biomarkers to profile distinct migraine subtypes should be utilized in clinical and research settings. Therefore, there is a need to include physical and psychophysical examinations aimed at assessing migraine features quantitatively.

PURPOSE

This paper aimed to discuss if increased pressure pain sensitivity and impaired cervical musculoskeletal function could be considered 1) as quantitative features of migraine and 2) if they could be used as biomarkers to profile migraine patients in distinct subtypes.

IMPLICATION

Increased pain sensitivity and cervical musculoskeletal impairments have been suggested as quantitative biomarkers to phenotype and subgroup migraine patients in clinical and research settings. This could provide the first step for a mechanistically-driven and personalized treatment approach according to migraine phenotypes.

Only cervical vertebrae C0-C2, not C3 are relevant for subgrouping migraine patients according to manual palpation and pain provocation: secondary analysis of a cohort study

BACKGROUND

Subgrouping of migraine patients according to the pain response to manual palpation of the upper cervical spine has been recently described. Based on the neuroanatomy and the convergence of spinal and trigeminal nerves in the trigeminocervical complex, the cervical segments C1 to C3 are potentially relevant. To date it has not been investigated whether palpation results of all upper cervical segments are based on one underlying construct which allows combining the results of several tests. Therefore, the aim of this secondary analysis of a cohort study was to determine whether results from all three segments form one construct.

METHODS

Seventy-one migraine patients with chronic or frequent episodic migraine diagnosed according to the international headache society classification version 3 were examined by one physiotherapist. Manual palpation using a posterior to anterior pressure was performed on the upper three cervical vertebrae unilaterally left and right. The results of the palpation according to the patients' responses were combined using factor analysis. In addition, item response theory (IRT) was used to investigate the structure of the response pattern as well as item difficulty and discrimination.

FINDINGS

Factor analysis (principal component) showed that the palpation of C3 loads less onto the underlying construct than the palpation of C1 and C2. Considering a cut-off value > 1.0, the eigenvalues of all three segments do not represent one underlying construct. When excluding the results from C3, remaining items form one construct. The internal consistency of the pain response to palpation of C1 and C2 is acceptable with a Cronbach's alpha of 0.69. IRT analysis showed that the rating scale model fits best to the pain response pattern. The discrimination value (1.24) was equal for all items. Item difficulty showed a clear hierarchical structure between the palpation of C1 and C2, indicating that people with a higher impairment are more likely to respond with referred pain during palpation of C2.

CONCLUSION

Statistical analysis confirms that results from the palpation of the cervical segments C1 and C2 in migraine patients can be combined. IRT analysis confirmed the ordinal pattern of the pain response and showed the higher probability of a pain response during palpation of C2. The pain response to C3 palpation is not relevant for unidimensional IRT analysis.

TRIAL REGISTRATION

German registry of clinical trials (DRKS00015995), Registered 20. December 2018, https://www.drks.de/drks_web/setLocale_EN.do.

Pain sensitivities predict prophylactic treatment outcomes of flunarizine in chronic migraine patients: A prospective study

BACKGROUND

We aimed to assess the differences in quantitative sensory testing between chronic migraine and healthy controls and to explore the association between pain sensitivities and outcomes in chronic migraine following preventive treatment.

METHODS

In this prospective open-label study, preventive-naïve chronic migraine and healthy controls were recruited, and cold, heat, mechanical punctate, and pressure pain thresholds over the dermatomes of first branch of trigeminal nerve and first thoracic nerve were measured by quantitative sensory testing at baseline. Chronic migraines were treated with flunarizine and treatment response was defined as ≥50% reduction in the number of monthly headache days over the 12-week treatment period.

RESULTS

Eighty-four chronic migraines and fifty age-and-sex-matched healthy controls were included in the analysis. The chronic migraine had higher cold pain thresholds over the dermatomes of the first branch of trigeminal nerve and the first thoracic nerve (p < 0.001 and < 0.001), lower pressure pain thresholds over the dermatomes of the first thoracic nerve (p = 0.003), heat pain thresholds over the dermatomes of the first branch of the trigeminal nerve and the first thoracic nerve (p < 0.001 and p = 0.015) than healthy controls. After treatment, 24/84 chronic migraine had treatment response. The responders with relatively normal pain sensitivity had higher heat pain thresholds over the dermatome of the first branch of the trigeminal nerve (p = 0.002), mechanical punctate pain thresholds over the dermatomes of the first branch of the trigeminal nerve (p = 0.023), and pressure pain thresholds over the dermatomes of the first branch of the trigeminal nerve (p = 0.026) than the hypersensitive non-responders. Decision tree analysis showed that patients with mechanical punctate pain threshold over the dermatomes of the first branch of the trigeminal nerve > 158 g (p = 0.020) or heat pain threshold over the dermatome of the first branch of the trigeminal nerve > 44.9°C (p = 0.002) were more likely to be responders.

CONCLUSIONS

Chronic migraine were generally more sensitive compared to healthy controls. Preventive treatment with flunarizine should be recommended particularly for chronic migraine who have relatively normal sensitivity to mechanical punctate or heat pain.Trial registration: This study was registered on ClinicalTrials.gov (Identifier: NCT02747940).

The Neck Disability Index Reflects Allodynia and Headache Disability but Not Cervical Musculoskeletal Dysfunction in Migraine

OBJECTIVE

The Neck Disability Index (NDI) is a self-rated disability tool originally developed for whiplash-associated disorders and validated in cervical musculoskeletal conditions. It is now commonly used to assess neck disability in migraine, but it is unknown whether NDI scores relate to migraine and hypersensitivity, cervical musculoskeletal dysfunction, or both. This single-blinded observational study aimed to determine whether the presence of cervical musculoskeletal dysfunction, migraine features, and hypersensitivity predict NDI scores and whether alternate versions of the NDI (NDI-physical, NDI-8, NDI-5) relate more to cervical musculoskeletal dysfunction.

METHODS

Migraine and neck pain features, the Headache Impact Test (HIT-6), NDI, Allodynia Symptom Checklist (ASC12), and pressure pain thresholds were assessed in 104 participants with migraine and neck pain, 45 previously identified with cervical musculoskeletal dysfunction and 59 without. The NDI score was regressed on the presence or absence of cervical dysfunction, migraine features, HIT-6, total pressure pain threshold, and ASC12 while accounting for neck pain features. The presence of cervical dysfunction was regressed on the scores of NDI versions.

RESULTS

The ASC12 (standardized ß = 0.20) and HIT-6 (standardized ß = 0.18) were significantly predictive of total NDI score, as were neck pain intensity (standardized ß = 0.32) and frequency (standardized ß = 0.44). No scores from alternate NDI versions related to cervical dysfunction.

CONCLUSION

The NDI score is a complex measure of neck disability influenced by migraine disability and hypersensitivity beyond the presence of cervical musculoskeletal dysfunction. This has implications for the clinical interpretation of NDI scores in patients with migraine.

IMPACT

Many patients with migraine and neck pain report neck disability; therefore, it is important to understand if migraine impacts neck disability. The results of this study indicate that clinicians need to consider migraine-related disability and hypersensitivity when managing neck disability in this population.

Experimental evidence of a functional relationship within the brainstem trigeminocervical complex in humans

ABSTRACT

The existence of a trigeminocervical complex (TCC) has been suggested based on animal data, but only indirect evidence exists in humans. We investigated the functional relationship between the trigeminal and the occipital region by stimulating one region and measuring electrical pain thresholds (EPTs) of the corresponding opposite region. This study consists of two single-blinded, randomized protocols. 40 healthy participants were recruited in the propaedeutic Protocol I. EPTs were measured on the V1 and the greater occipital nerve (GON) dermatome bilaterally as well as on the left forearm longitudinally before and after application of topical capsaicin. Protocol II was then online pre-registered and, additionally, the ipsilateral trigeminal dermatomes V2 and V3 were tested. GON stimulation increased the EPT ipsilateral at V1 after 20 minutes (p=0.006) compared to baseline, whereas trigeminal stimulation increased the EPT at the ipsilateral (p=0.023) as well as the contralateral GON (p=0.001) following capsaicin application. Protocol II confirmed these results and additionally showed that GON stimulation with capsaicin increased EPTs ipsilateral at all three trigeminal dermatomes and that trigeminal stimulation on V1 led to an ipsilateral increase of EPTs at GON, V2 and V3. Our data suggest a strong functional interplay between the trigeminal and occipital system in humans. The fact that stimulation of one of these dermatomes increases the electrical pain threshold of the respective other nerve could be explained by segmental inhibition on brainstem level.