High concurrent validity between digital and analogue algometers to measure pressure pain thresholds in healthy participants and people with migraine: a cross-sectional study.

BACKGROUND: Pressure pain thresholds (PPTs) are commonly assessed to quantify mechanical sensitivity in various conditions, including migraine. Digital and analogue algometers are used, but the concurrent validity between these algometers is unknown. Therefore, we assessed the concurrent validity between a digital and analogue algometer to determine PPTs in healthy participants and people with migraine. METHODS: Twenty-six healthy participants and twenty-nine people with migraine participated in the study. PPTs were measured interictally and bilaterally at the cephalic region (temporal muscle, C1 paraspinal muscles, and trapezius muscle) and extra-cephalic region (extensor carpi radialis muscle and tibialis anterior muscle). PPTs were first determined with a digital algometer, followed by an analogue algometer. Intraclass correlation coefficients (ICC3.1) and limits of agreement were calculated to quantify concurrent validity. RESULTS: The concurrent validity between algometers in both groups was moderate to excellent (ICC3.1 ranged from 0.82 to 0.99, with 95%CI: 0.65 to 0.99). Although PPTs measured with the analogue algometer were higher at most locations in both groups (p < 0.05), the mean differences between both devices were less than 18.3 kPa. The variation in methods, such as a hand-held switch (digital algometer) versus verbal commands (analogue algometer) to indicate when the threshold was reached, may explain these differences in scores. The limits of agreement varied per location and between healthy participants and people with migraine. CONCLUSION: The concurrent validity between the digital and analogue algometer is excellent in healthy participants and moderate in people with migraine. Both types of algometer are well-suited for research and clinical practice but are not exchangeable within a study or patient follow-up.

Fluctuations in local and widespread mechanical sensitivity throughout the migraine cycle: a prospective longitudinal study.

BACKGROUND: People with migraine have localised (i.e., cephalic) mechanical sensitivity. There is uncertainty regarding widespread (i.e., extra-cephalic) mechanical sensitivity and variations in mechanical sensitivity throughout the migraine cycle. Therefore, this study aimed (1) to comprehensively assess mechanical sensitivity in both cephalic and extra-cephalic regions during the preictal, ictal, postictal and interictal phases; and (2) to compare these findings with mechanical sensitivity at corresponding time-points and locations in healthy participants. METHODS: According to sample size calculations, 19 people with migraine and 19 matched healthy volunteers participated in a prospective longitudinal study. Pressure pain thresholds were evaluated in three cephalic regions (temporalis, upper trapezius and C1 paraspinal muscles) and two extra-cephalic regions (extensor carpi radialis and tibialis anterior muscle) with a digital algometer during the four phases of the migraine cycle in people with migraine and at corresponding intervals and locations in healthy participants. Linear mixed model analyses with a random intercept were used. RESULTS: People with migraine had increased mechanical sensitivity in cephalic and extra-cephalic regions in all phases of the migraine cycle compared to healthy participants. Furthermore, this mechanical sensitivity was more severe in the preictal, ictal and postictal phase compared to the interictal phase in cephalic and extra-cephalic regions. CONCLUSION: People with migraine have localised as well as widespread mechanical sensitivity compared to healthy participants. This sensitivity is even more pronounced immediately before, during and after a migraine attack.

Pressure pain thresholds over the cranio-cervical region in headache: a systematic review and meta-analysis.

BACKGROUND: Sensitivity of tissues can be measured by algometry. Decreased pressure pain thresholds over the cranio-cervical area are supposed to reflect signs of sensitization of the trigemino-cervical nucleus caudalis. A systematic review was conducted to assess the current scientific literature describing pressure pain threshold (PPT) values over the cranio-cervical region in patients with migraine, tension-type headache (TTH), and cervicogenic headache (CeH). A literature search was executed in three databases. The search strategy included the following keywords: migraine, TTH, CeH, PPT and algometry. A total of 624 papers was identified of which relevant papers were subsequently assessed for methodological quality. Twenty-two selected papers were assessed by two independent reviewers and the majority of studies scored low risk of bias on the selected items. Mean PPT values of several sites measured in the cranio-cervical region in patients with migraine, chronic TTH and CeH scored lower values compared to controls. The trapezius muscle (midpoint between vertebrae C7 and acromion) was the most frequently targeted site and showed significantly lower PPT values in adults with migraine (pooled standardized mean difference kPa: 1.26 [95%CI -1.71, -0.81]) and chronic TTH (pooled standardized mean difference kPa: -2.00 [95%CI -2.93, -1.08]). Most studies found no association between PPT values and headache characteristics such as frequency, duration or intensity. Further standardization of PPT measurement in the cranio-cervical region is recommended.

Minimal clinically important change on the Headache Impact Test-6 questionnaire in patients with chronic tension-type headache.

OBJECTIVE: To determine the minimal clinically important change (MCIC) in Headache Impact Test-6 (HIT-6) score in patients with chronic tension-type headache (CTTH). METHODS: The HIT-6 was administered at baseline and at 8 weeks follow-up in a cohort of 186 participants with CTTH who received manual therapy or usual care by their general practitioner. An anchor-based method was used to determine the MCIC, with the external criterion (anchor) being based on general perceived improvement ('much improved or very much improved' on a 7-point Likert scale) in combination with 50% reduction in headache days. Using receiver operating characteristic (ROC) curve analysis we defined an optimal cut-off score discriminating between improved and not improved participants. RESULTS: The optimal cut-off point for the MCIC for the HIT-6 was -8 points, on a total scale range of 42 points. CONCLUSION: A clinically relevant improvement in patients with CTTH is reflected by a decrease of at least 8 points on the HIT-6.

Clinical variables associated with recovery in patients with chronic tension-type headache after treatment with manual therapy.

The aims of this study were to describe the course of chronic tension-type headache (CTTH) in participants receiving manual therapy (MT), and to develop a prognostic model for predicting recovery in participants receiving MT. Outcomes in 145 adults with CTTH who received MT as participants in a previously published randomised clinical trial (n=41) or in a prospective cohort study (n=104) were evaluated. Assessments were made at baseline and at 8 and 26 weeks of follow-up. Recovery was defined as a 50% reduction in headache days in combination with a score of 'much improved' or 'very much improved' for global perceived improvement. Potential prognostic factors were analyzed by univariable and multivariable regression analysis. After 8 weeks 78% of the participants reported recovery after MT, and after 26 weeks the frequency of recovered participants was 73%. Prognostic factors related to recovery were co-existing migraine, absence of multiple-site pain, greater cervical range of motion and higher headache intensity. In participants classified as being likely to be recovered, the posterior probability for recovery at 8 weeks was 92%, whereas for those being classified at low probability of recovery this posterior probability was 61%. It is concluded that the course of CTTH is favourable in primary care patients receiving MT. The prognostic models provide additional information to improve prediction of outcome.

Effectiveness of manual therapy for chronic tension-type headache: a pragmatic, randomised, clinical trial.

OBJECTIVE: To evaluate the effectiveness of manual therapy (MT) in participants with chronic tension-type headache (CTTH). SUBJECTS AND METHODS: We conducted a multicentre, pragmatic, randomised, clinical trial with partly blinded outcome assessment. Eighty-two participants with CTTH were randomly assigned to MT or to usual care by the general practitioner (GP). Primary outcome measures were frequency of headache and use of medication. Secondary outcome measures were severity of headache, disability and cervical function. RESULTS: After 8 weeks (n = 80) and 26 weeks (n = 75), a significantly larger reduction of headache frequency was found for the MT group (mean difference at 8 weeks, -6.4 days; 95% CI -8.3 to -4.5; effect size, 1.6). Disability and cervical function showed significant differences in favour of the MT group at 8 weeks but were not significantly different at 26 weeks. CONCLUSIONS: Manual therapy is more effective than usual GP care in the short- and longer term in reducing symptoms of CTTH. Dutch Trial Registration no. TR 1074.

Effectiveness of manual therapy compared to usual care by the general practitioner for chronic tension-type headache: design of a randomised clinical trial.

BACKGROUND: Patients with Chronic Tension Type Headache (CTTH) report functional and emotional impairments (loss of workdays, sleep disturbances, emotional well-being) and are at risk for overuse of medication. Manual therapy may improve symptoms through mobilisation of the spine, correction of posture, and training of cervical muscles.We present the design of a randomised clinical trial (RCT) evaluating the effectiveness of manual therapy (MT) compared to usual care by the general practitioner (GP) in patients with CTTH. METHODS AND DESIGN: Patients are eligible for participation if they present in general practice with CTTH according to the classification of the International Headache Society (IHS).Participants are randomised to either usual GP care according to the national Dutch general practice guidelines for headache, or manual therapy, consisting of mobilisations (high- and low velocity techniques), exercise therapy for the cervical and thoracic spine and postural correction. The primary outcome measures are the number of headache days and use of medication. Secondary outcome measures are severity of headache, functional status, sickness absence, use of other healthcare resources, active cervical range of motion, algometry, endurance of the neckflexor muscles and head posture. Follow-up assessments are conducted after 8 and 26 weeks. DISCUSSION: This is a pragmatic trial in which interventions are offered as they are carried out in everyday practice. This increases generalisability of results, but blinding of patients, GPs and therapists is not possible.The results of this trial will contribute to clinical decision making of the GP regarding referral to manual therapy in patients with chronic tension headache.