Spinal Pain and Autonomic Responses to Chiropractic Care

Study Overview
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Brief Summary
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This randomized, single-blinded study will investigate the effects of Spinal Manipulative Therapy on Heart Rate Variability and Pain Sensitivity in a population of patients with recurrent and persistent neck pain. Alongside, the study will also develop a clinical test for Conditioned Pain Modulation and investigate its predictive properties.

Detailed Description
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Previously, Spinal Manipulative Therapy (SMT) was thought to mechanically affect the restoration of muscular and joint function, by normalising muscle tension and joint mobility. However, recent research has suggested that SMT may be influencing the incoming/ascending pain signals and/or the excitability of the central pain regulating mechanisms. People with chronic neck/shoulder pain have been found to have a disturbance of the Autonomic Nervous System (ANS). Little is known about the changes in the ANS and its relation to changes in pain in a series of treatments conducted in a clinical setting. This multicentre randomized controlled clinical trial will be carried out in multimodal primary care clinics where both physiotherapists and chiropractors are consulted for musculoskeletal issues are selected to minimize selection bias from the patient's pre-desired treatment modality. The subjects will be recruited among patients seeking care for persistent or recurrent Neck pain (NP), either self-selected or through referrals from general practitioners in the local areal. The aim is to study the effect of SMT and stretching exercises compared to stretching exercises alone, two well-known interventions for NP, during a two-week treatment regimen. The primary outcome is the activity of the autonomic nervous system (Heart Rate Variability (HRV), but also Conditioned Pain Modulation (CPM) will be measured. HRV and CPM will be measured at baseline, prior to the third treatment and after the fourth treatment. The subjective pain experience will be investigated by using two different instruments accessing pain intensity and the affective quality of pain, asked at the assessments during the two weeks of treatment and 2 months after the period of intervention ends. Highly structured data collection procedures should provide reliable data to answer these questions. The study utilizes normal clinical procedures, which should aid the transferability of the results.

Official Title
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The Effect of Spinal Manipulative Therapy on Heart Rate Variability and Pain, and the Predictive Value of Conditioned Pain Modulation

Conditions
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Neck Pain

Intervention / Treatment
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* Other: Stretching and Spinal manipulative therapy
* Other: Stretching


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: minimum 18 years, able to read and understand Swedish, persistent or recurrent Neck Pain (duration of current episode more than 6 months and at least one previous episode of NP), no chiropractic treatment during the previous 3 months. Exclusion Criteria: conditions or medications that will affect the Heart Rate Variability measurements (cardiovascular disease, diabetes, pregnancy, obesity, currently using pain-reducing medication, steroids or antidepressants), all contraindications to manual treatment, (anything that could seriously aggravate the pain (such as inflammatory conditions) or signal cerebrovascular injuries (previous drop attacks or a recent episode of new headache or dizziness).

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Subjects will be randomized into two arms: 1: stretching exercises only, 2: stretching exercises and Spinal Manipulative Therapy
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intervention<br>Stretching and Spinal Manipulative Therapy | Other: Stretching and Spinal manipulative therapy<br>* Subjects will be instructed to perform a series of progressively difficult stretching exercises for the neck and upper back muscles. In addition, subjects will be treated with Spinal manipulative therapy<br>|
| Active Comparator: Comparator<br>Stretching | Other: Stretching<br>* Subjects will be instructed to perform a series of progressively difficult stretching exercises for the neck and upper back muscles.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Heart Rate Variability | The variation in beat-to-beat heart rate is an indicator of parasympathetic and sympathetic modulation of the heart rhythm. | 1 and 2 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Pain sensitivity | Conditioned Pain Modulation is assessed using a thumb clamp and a cold pressor test. | 1 and 2 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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neck pain, spinal manipulative therapy, heart rate variability, conditioned pain modulation