An interventional study of Stretching and Spinal manipulative therapy and Stretching in Neck Pain, sponsored by Karolinska Institutet. Completed at 2 sites in Sweden. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-12-24.
Sponsored by Karolinska Institutet · Not applicable, Interventional, and Treatment
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.
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.
1,232 studies on the registry are indexed under Neck Pain; 255 are open to participants now.
This study's enrollment of 131 is above the median of 52 across 1,004 interventional studies indexed under Neck Pain.
Browse Neck Pain studies →Karolinska Institutet is the lead sponsor of 1,113 studies on the registry; 267 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Stretching and Spinal Manipulative Therapy
Other: Stretching and Spinal manipulative therapy
Stretching
Other: Stretching
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
Subjects will be instructed to perform a series of progressively difficult stretching exercises for the neck and upper back muscles.
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. It is measured as the time between two R-waves on the ECG and measured in ms.
Time frame: 2 weeks, the change is reported between baseline-2 weeks
Change in Conditioned Pain Modulation, Measured as the Difference in Pain Intensity Between Two Conditions .
Conditioned Pain Modulation is assessed using a thumb clamp and a cold pressor test. Pain is rated on the Numeric Rating Scale, ranging from 10 (unbearable pain) to 0 (no pain). The outcome is the difference between these two measurements.
Time frame: The test is done at baseline and again at 2 weeks, and the outcome is the difference between these two scores
Change in Pain Intensity
Self-reported, using the Numeric Rating Scale (0-10). High scores indicate more severe pain. The outcome is the difference between the scores measured at baseline at at two weeks.
Time frame: 2 weeks, pain intensity is assessed at Baseline and after 2 weeks, the outcome is the difference between them.
Change in Disability Score
Neck Disability Index (10 questions, answer options 1-6, summary score, higher score indicating higher disabiity), reported at baseline and at 2 weeks follow up. The measure is the difference between these two scores
Time frame: 2 weeks
Common Side-effects
Description and count of common side effects, data collected through a single question using text messages. Thus, the participants described their side-effects, which were categorized and counted.
Time frame: 1 week
| Milestone | Intervention | Comparator |
|---|---|---|
| Started | 66 | 65 |
| Responders | 27 | 26 |
| Non-responders | 27 | 25 |
| Completed | 54 | 41 |
| Not completed | 12 | 24 |
The variation in beat-to-beat heart rate is an indicator of parasympathetic and sympathetic modulation of the heart rhythm. It is measured as the time between two R-waves on the ECG and measured in ms.
| ms | Intervention | Comparator |
|---|---|---|
| Change in Heart Rate Variability | 843 ± 129 | 887 ± 138 |
Conditioned Pain Modulation is assessed using a thumb clamp and a cold pressor test. Pain is rated on the Numeric Rating Scale, ranging from 10 (unbearable pain) to 0 (no pain). The outcome is the difference between these two measurements.
| NRS change score | Clinical Responders | Clinical non-responders |
|---|---|---|
| Change in Conditioned Pain Modulation, Measured as the Difference in Pain Intensity Between Two Conditions . | -3.3 ± 0.2 | 0.2 ± 0.2 |
Self-reported, using the Numeric Rating Scale (0-10). High scores indicate more severe pain. The outcome is the difference between the scores measured at baseline at at two weeks.
| score on a scale | Intervention | Comparator |
|---|---|---|
| Change in Pain Intensity | 1.1 ± 2.085 | 1.1 ± 2.101 |
Neck Disability Index (10 questions, answer options 1-6, summary score, higher score indicating higher disabiity), reported at baseline and at 2 weeks follow up. The measure is the difference between these two scores
| score on a scale | Intervention | Comparator |
|---|---|---|
| Change in Disability Score | -2.1 ± 4.58 | -1.9 ± 4.21 |
Description and count of common side effects, data collected through a single question using text messages. Thus, the participants described their side-effects, which were categorized and counted.
| Participants | Intervention | Comparator |
|---|---|---|
| Common Side-effects | 3 | 1 |
Collected over The participants were asked to report adverse events 1 day after the first treatment was administered.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Intervention | 0/66 (0%) | 0/66 (0%) | 3/66 (4.5%) |
| Comparator | 0/65 (0%) | 0/65 (0%) | 1/65 (1.5%) |
| Event | Intervention | Comparator |
|---|---|---|
| MinorMusculoskeletal and connective tissue disorders | 3/66 | 1/65 |
| Age, Continuous(Years) | Intervention | Comparator | Total |
|---|---|---|---|
| Mean | 57 ± 14 | 57.5 ± 36 | 57.2 ± 13.8 |
| Sex: Female, Male(Participants) | Intervention | Comparator | Total |
|---|---|---|---|
| Female | 37 | 36 | 73 |
| Male | 29 | 29 | 58 |
| Race and Ethnicity Not Collected(Participants) | Intervention | Comparator | Total |
|---|---|---|---|
| Count of participants | — | — | 0 |
| Heart rate variability(ms) | Intervention | Comparator | Total |
|---|---|---|---|
| Mean | 27 ± 29 | 29 ± 21 | 28 ± 25 |
Documents are hosted by the registry — open the source record to download them.
Plan to share: No — Anonymized information may be shared with other researchers upon request, pending ethical approval.
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Karolinska Institutet