Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12621001276842
Ethics application status
Approved
Date submitted
9/09/2021
Date registered
21/09/2021
Date last updated
13/09/2022
Date data sharing statement initially provided
21/09/2021
Type of registration
Retrospectively registered

Titles & IDs
Public title
Impact of chiropractic care on brain control of eye movements in individuals with recurrent neck pain
Scientific title
The Effects of 8-weeks of Chiropractic Care on the Vestibular-ocular and cervico-ocular reflex in a subclinical neck pain population: A randomized control trial
Secondary ID [1] 302432 0
Nil
Universal Trial Number (UTN)
U1111-1258-9224
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Neck dysfunction 319239 0
Impaired Cerebellar Plasticity 319240 0
Impaired Head and Neck proprioception 319323 0
Impaired Neck Mobility 323496 0
Condition category
Condition code
Musculoskeletal 317202 317202 0 0
Other muscular and skeletal disorders
Physical Medicine / Rehabilitation 317203 317203 0 0
Other physical medicine / rehabilitation

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The intervention will consist of spinal adjustments which will be either high-velocity, low-amplitude thrusts to the spine or pelvic joints or instrument assisted adjustments as well as myofascial release of associated muscles. Treatment will be personalized to each individual in the treatment arm since individuals may have different areas of associated joint dysfunction and associated myofascial pain. These are standard adjustment techniques used by chiropractors. These adjustment techniques have also previously been used in studies that have investigated the neurophysiological effects of chiropractic care. The entire spine and both sacroiliac joints will be assessed for the presence of spinal dysfunction and adjusted where deemed clinically necessary by a chiropractor over an 8-week period. Associated myofascial pain will be treated by manual myofascial release of “trigger point” areas. The registered chiropractor has been practicing for over 31 years and has the expertise to be providing the intervention in this study. A second chiropractor, with five to ten years of experience, will be available should the primary chiropractor experience illness or injury. The subclinical neck pain (SCNP) treatment group will receive 8 weeks of chiropractic intervention since past work has suggested that 6 to 8 weeks are required to consolidate neural changes. The treatment frequency will be twice per week, tapering off if clinically indicated, at the discretion of the treating chiropractor. Each treatment session will be approximately 20 minutes in duration with the first session being at least 45 minutes, to acquire details about their medical history and perform a physical examination and assessment of areas of spinal dysfunction and associated myofascial findings. The clinical indicators that will be used to assess the function of the spine prior to and after each chiropractic adjustment session will include assessing for tenderness to palpation of the relevant joints, manually palpating for restricted intersegmental range of motion, assessing for palpable asymmetric intervertebral muscle tension, and any abnormal or blocked joint play and end-feel of the joints. All of these biomechanical characteristics are used by chiropractors as clinical indicators of joint dysfunction. Areas of myofascial pain that have local tenderness and refer pain on palpation will be treated by the chiropractor using manually applied trigger point therapy. The chiropractic care will be performed at Ontario Tech University, where the registered chiropractors administering the treatment practice. In order to monitor adherence to the intervention, the chiropractor will provide a report of the number of sessions attended.

The healthy (non-SCNP) participants will undergo the outcome measures once, at baseline only. The baseline outcome measures will be compared between the SCNP and healthy groups, to compare neurophysiological differences between SCNP participants and the healthy participants.
Intervention code [1] 318715 0
Rehabilitation
Intervention code [2] 321620 0
Treatment: Other
Comparator / control treatment
The SCNP control participants will undergo baseline testing, followed by an 8-week period of no chiropractic intervention, similar duration to the SCNP treatment group’s treatment duration. The change in outcome measures (i.e. difference between follow-up and baseline) will be compared between the SCNP control group and the SCNP treatment group, to examine the effectiveness of 8-weeks of chiropractic care in improving outcome measures (related to neck proprioception, and cerebellar plasticity). The SCNP control group will be offered a period of free chiropractic care upon completion of their eight-week follow-up measures.
Control group
Active

Outcomes
Primary outcome [1] 325278 0
Cerebellar Plasticity – Cervico-ocular reflex (COR):
The COR measures movements of the neck relative to the trunk, which are measured by recording reflexive eye movements in response to trunk rotation. Participants will be secured in a rotating chair that allows for low velocity trunk rotation (e.g. less than 5 degrees per second), while the head is kept still. The EyeLink-II high speed eye tracking camera system will be used to record the gaze position of the eyes and the head reference markers during rotation of the trunk, while head movements will be accurately recorded with 3D Motion tracking cameras. COR gain, which is the ratio of eye movement relative to trunk movement will be recorded.
Timepoint [1] 325278 0
Measure will be assessed at baseline and at follow-up (e.g. after 8 weeks of either chiropractic care or a no treatment control period).
Primary outcome [2] 325354 0
Cerebellar Plasticity – Vestibulo-ocular reflex (VOR):
The VOR keeps the eyes on target despite head and/or body movements, whether these movements are self-produced (active VOR) or externally imposed (passive VOR). The EyeLink-II high speed eye-tracking system will be used to record the gaze position of the eyes and head reference markers. The ability to adapt and change the gain of the VOR will be measured by subtly shifting the position of a target dot on a computer monitor and recording the participant’s eye position.
Timepoint [2] 325354 0
Measure will be assessed at baseline and at follow-up (e.g. after 8 weeks of either chiropractic care or a no treatment control period).
Primary outcome [3] 328837 0
Repositioning Accuracy of the Head and Neck:

The ability to reposition the head to the target angle (i.e. target head position) will be done using a cervical range of motion (C-ROM) device, while participant’s vision is occluded so that the participant has to rely on proprioception.
Timepoint [3] 328837 0
Measure will be assessed at baseline and at follow-up (e.g. after 8 weeks of either chiropractic care or a no treatment control period).
Secondary outcome [1] 400575 0
Neck ROM
A cervical range of motion device will be used to measure the degrees of neck movement in the three planes – sagittal (front, back), Coronal (left and right lateral flexion), Transverse (right and left rotation).
Timepoint [1] 400575 0
Measure will be assessed at baseline and at follow-up (e.g. after 8 weeks of either chiropractic care or a no treatment control period).
Secondary outcome [2] 400576 0
Self-reported Current Neck Pain
Participants will be asked to complete the Neck disability Index questionnaire, to determine their neck pain-related disability, at the moment of administration.
Timepoint [2] 400576 0
Measure will be assessed at baseline and at follow-up (e.g. after 8 weeks of either chiropractic care or a no treatment control period).
Secondary outcome [3] 400577 0
Self-reported Neck Pain – Chronic Pain Grade Scale
Participants will be asked to complete the chronic pain grade scale, which will provide information on their neck pain intensity and neck pain-related disability (if any) in the past 6 months. The responses to this questionnaire will be used to confirm eligibility to participate in this study.
Timepoint [3] 400577 0
Measure will be assessed at baseline and at follow-up (e.g. after 8 weeks of either chiropractic care or a no treatment control period).
Secondary outcome [4] 400578 0
Self-reported Current Neck Pain – Visual Analog Scale
Participants will be asked to complete the neck pain visual analog scale questionnaire, to determine their level of neck pain, at the moment of administration.
Timepoint [4] 400578 0
Measure will be assessed at baseline and at follow-up (e.g. after 8 weeks of either chiropractic care or a no treatment control period).
Secondary outcome [5] 400579 0
Self-reported SMI
Participants will be asked to complete the Spine Dysfunction, Stress & Sensory-Motor Integration Questionnaire, assessing their central neural processing during various functional/ daily tasks.
Timepoint [5] 400579 0
Measure will be assessed at baseline and at follow-up (e.g. after 8 weeks of either chiropractic care or a no treatment control period).
Secondary outcome [6] 400580 0
Recruitment Rate is defined as the number of participants that are recruited per site per a month. Recruitment rate will be calculated as the total number of participants that were recruited and randomized divided by total of number of months spent recruiting participants, at the one site. . The lead researcher will keep track of those that have been recruited and randomized by documenting it in an excel spreadsheet.
Timepoint [6] 400580 0
Measure will be assessed at enrolment completion.
Secondary outcome [7] 400581 0
Retention Rate is defined as the number of recruited and randomized participants who have full sets of valid data for the outcome measures collected. This will be expressed as a percentage, number of participants with complete data sets divided by total number of participants. The lead researcher will denote on an excel spreadsheet that have a full set of valid data as she will also know the total of number of participants.
Timepoint [7] 400581 0
Measure will be assessed at follow-up (e.g. after the completion of either chiropractic care or a no treatment control period).
Secondary outcome [8] 400582 0
Adverse events in response to the chiropractic treatment: A report will be given to the researchers by the chiropractor, which will contain information on the number of participant(s) and what the adverse event was/were. Examples of known/possible adverse events include transient increases in pain and/or stiffness, generally lasting less than 24 hours, when this does occur. This is described to participants in the informed consent for chiropractic care required in the province of Ontario.
Timepoint [8] 400582 0
Measure will be assessed during the completion of chiropractic care for the SCNP treatment group.
Secondary outcome [9] 400583 0
Compliance to the chiropractic treatment: This will be reflected by chiropractor’s report to the researcher. It will contain their notes on the progression of each participant’s improvement following their chiropractic treatment.
Timepoint [9] 400583 0
Measure will be assessed during the completion of chiropractic care for the SCNP treatment group.
Secondary outcome [10] 400584 0
Acceptability of interventions: This will be assessed qualitatively by asking participants who were allocated to the treatment group about observable changes (i.e. reduced pain, improved mobility, etc.) following the completion of their chiropractic treatment at follow-up. A semi-structured one-to-one interview with the researcher that will ask questions about concepts, such as: observed changes in body movement or functionality since the start of treatment versus now, etc..
Timepoint [10] 400584 0
Measure will be assessed at follow-up (e.g. after the completion of chiropractic care) for the treatment group.

Eligibility
Key inclusion criteria
Healthy and neck pain participants must be males and females aged 18 – 35, who are attending Ontario Tech University. Neck pain participants are to have mild-to-moderate neck pain and/or neck stiffness for at least 6 months and not started any treatment in the past 4 weeks or not yet sought treatment, this population is known as subclinical neck pain. Healthy participants are to be free from chronic or recurrent neck, shoulder, or elbow pain and have full pain-free neck and shoulder range of motion for at least 3 months prior to data collection. All participants will be screened for these inclusion and exclusion criteria using the chronic pain grade scale questionnaire (see secondary outcome 3). Individuals must have a score between 1 and 3 (out 4) on the Chronic Pain Grade Scale Questionnaire for time periods when they do experience neck pain, and a history of recurrent neck pain to be eligible for the SCNP group. Healthy participants must have a score of less than 1 on the Chronic Pain Grade scale. Because participants are “subclinical”, not all participants will have a progressed to the point where their pain has led to disability; therefore, to ensure we capture a range of SCNP participants, we plan to include participants’ who scored 1 to 3 on the Chronic Pain Grade scale questionnaire, and/or >30mm for intensity of pain on the visual analog scale. Right-handed individuals will be tested due to known differences in cortical excitability and sensorimotor processing between dominant and non-dominant limbs. Participants who score > +40 on the Edinburgh Handedness Inventory (Deemed right-handed) will be included in this study. Participants that are deemed ambidextrous, but have a strong inclination for right-hand dominance will also be included in the study. The SCNP participants will also screened by a registered chiropractor to ensure that they have a spinal joint dysfunction(s).
Minimum age
18 Years
Maximum age
35 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
SCNP participants (control or intervention group) must not have any contraindications to spinal adjustments, such as spinal instability, recurrent dizziness or vertigo, hypertension or upper limb radiculopathy. Participants cannot have any neurological conditions that are known to impact neural function and/or neural processing (e.g. multiple sclerosis, stroke, Parkinson’s etc.). All participants will be screened for these inclusion and exclusion criteria using a safety screening checklist. Left-handed participants will be excluded from the study (I.e. < -40 on the Edinburgh Handedness Inventory) due to known differences in neural processing in these individuals.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Participants will be screened by the treating practitioner for the inclusion and exclusion criteria before enrollment. Once enrolled, the allocation intro treatment or control (no treatment) group will be performed by the researcher opening a numbered envelope which has been pre-populated with the participant allocation stated on a piece of paper inside the envelope.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Randomization will be carried out using an Excel Random number generator.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?



The people analysing the results/data
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Statistical methods / analysis
GPOWER statistical software indicates that for a medium effect size of 0.5 with an alpha level of 0.05 and a power level of 0.95 (set high so as not to risk making a type II error), 12 subjects are needed in each group for our repeated measures designs with pre-planned contrasts to baseline. We aim to recruit 24 SCNP participants per group (intervention vs control) to allow for dropouts and potentially smaller effect sizes for some of our proposed measures.
Baseline group differences between the SCNP vs. Healthy (non-SCNP)) will be compared using independent samples t-tests. Multifactorial repeated measures ANOVA will be used to assess for within and between differences for the SCNP groups. TIME (pre and post intervention measures) and INTERVENTION (Chiropractic care vs no intervention) will be used as factors. A priori pairwise comparisons of the pre and post intervention data will be carried out when an interactive effect is significant. Significance has been set at p = 0.05.

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
22/09/2021
Actual
20/09/2021
Date of last participant enrolment
Anticipated
31/01/2023
Actual
Date of last data collection
Anticipated
30/04/2023
Actual
Sample size
Target
72
Accrual to date
48
Final
Recruitment outside Australia
Country [1] 23030 0
Canada
State/province [1] 23030 0
Ontario

Funding & Sponsors
Funding source category [1] 306852 0
Other
Name [1] 306852 0
NCMIC Group, Inc.,
Country [1] 306852 0
United States of America
Funding source category [2] 306853 0
Charities/Societies/Foundations
Name [2] 306853 0
Australian Spinal Research Foundation
Country [2] 306853 0
Australia
Funding source category [3] 306854 0
Government body
Name [3] 306854 0
Natural Sciences and Engineering Research Council of Canada
Country [3] 306854 0
Canada
Primary sponsor type
Individual
Name
Bernadette Murphy
Address
Faculty of Health Sciences,
University of Ontario Institute of Technology
2000 Simcoe St North,
Oshawa, Ontario
L1G 0C5
Country
Canada
Secondary sponsor category [1] 307412 0
Individual
Name [1] 307412 0
Paul Yielder
Address [1] 307412 0
Faculty of Health Sciences,
University of Ontario Institute of Technology
2000 Simcoe St North,
Oshawa, Ontario
L1G 0C5
Country [1] 307412 0
Canada
Other collaborator category [1] 281496 0
Individual
Name [1] 281496 0
Heidi Haavik
Address [1] 281496 0
Director of Research
New Zealand College of Chiropractic
6 Harrison Road, Mt Wellington, Auckland, 1060 PO Box 113-044, Newmarket, Auckland, 1149
Country [1] 281496 0
New Zealand

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 307013 0
University of Ontario Institute of Technology Research Ethics Board
Ethics committee address [1] 307013 0
2000 Simcoe St North,
Oshawa, Ontario,
Canada, L1G 0C5
Ethics committee country [1] 307013 0
Canada
Date submitted for ethics approval [1] 307013 0
13/07/2018
Approval date [1] 307013 0
28/10/2018
Ethics approval number [1] 307013 0
14991

Summary
Brief summary
Research shows that neck pain is a significant burden that affects 30-50% of the population every year. Research is also showing that neck pain affects the way people perform movements and perceive their body positions in space. In past studies, our lab group has shown that these effects can be attributed to differences in how individuals with neck pain process sensory information. The current study will examine whether there are differences in how individuals with and without neck pain perform rapid eye movements. These movements are of interest because their control relies on sensory processing in distinct brain regions, and any differences in control may highlight impacted brain regions in those experiencing neck pain. We also want to examine whether chiropractic treatment restores the ability of the brain to integrate eye and upper limb movement performance to levels more typical in healthy individuals. The purpose of the study is to: (1) assess whether SCNP leads to altered function in the brain regions responsible for VOR/COR; (2) determine if chiropractic care, compared with no treatment, is effective in enhancing the capacity for cerebellar plasticity, in individuals with a spinal dysfunction. It is hypothesized that individuals that receive treatment will see measurable changes in outcome measures compared to the control group.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 105738 0
Prof Bernadette Murphy
Address 105738 0
Faculty of Health Sciences
2000 Simcoe St North,
Oshawa, Ontario, L1G 0C5
Canada
Country 105738 0
Canada
Phone 105738 0
+19057218668
Fax 105738 0
Email 105738 0
[email protected]
Contact person for public queries
Name 105739 0
Prof Bernadette Murphy
Address 105739 0
Faculty of Health Sciences
2000 Simcoe St North,
Oshawa, Ontario, L1G 0C5
Canada
Country 105739 0
Canada
Phone 105739 0
+19057218668
Fax 105739 0
Email 105739 0
[email protected]
Contact person for scientific queries
Name 105740 0
Prof Bernadette Murphy
Address 105740 0
Faculty of Health Sciences
2000 Simcoe St North,
Oshawa, Ontario, L1G 0C5
Canada
Country 105740 0
Canada
Phone 105740 0
+19057218668
Fax 105740 0
Email 105740 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
Many of the outcome measures used in this study use advanced processing and hence unprocessed individual participant data will not shared since it is not meaningful. We intend to publish the average processed data for the groups, which have been anonymized (e.g. average of three measures for joint position sense, average of trials for VOR/COR).


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.