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Trial registered on ANZCTR

Registration number
Ethics application status
Submitted, not yet approved
Date submitted
Date registered
Date last updated
Date data sharing statement initially provided
Type of registration
Prospectively registered

Titles & IDs
Public title
The effect of instrument assisted spinal manipulation on mechanical pain sensitivity in healthy population compared to control: A feasibility randomised trial
Scientific title
The effect of instrument assisted spinal manipulation on mechanical pain sensitivity in healthy population compared to control: A feasibility randomised trial
Secondary ID [1] 301098 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Low back bain 317172 0
Condition category
Condition code
Musculoskeletal 315326 315326 0 0
Other muscular and skeletal disorders
Physical Medicine / Rehabilitation 315475 315475 0 0
Other physical medicine / rehabilitation

Study type
Description of intervention(s) / exposure
This trial involves using a small hand-held spring-loaded device that delivers an instrument assisted spinal manipulation (The Activator IV), a sham (Activator IV calibrated to produce no force) and a control group. Qualified Chiropractors with a minimum of 3 years experience will deliver the Activator treatment, Sham activator or control to a prone patient in a University research setting. The clinicians will deliver the randomly treatment either to the left or right of the L4 vertebra (targeted to the L4 pedicle). This is applied randomly in order to decrease bias due to participant's dominant side hand and will not be part of the analysis.
Patients are required to meet the inclusion/exclusion criteria and will be assessed by the Clinicians. Pre-treatment baseline testing will be performed using a Wagner Pain Test algometer with a 1cm2 rubber probe. Each patient will receive one treatment with testing performed by a different clinician.

The Activator or sham procedure involves placing the small hand-held spring-loaded device at the level of L4, producing a high-velocity low amplitude thrust (121-211.6N). This procedure including locating the L4 pedicle and delivering the thrust lasts only a few seconds. The sham is designed to simulate the Activator treatment without producing any force(0N). Post-treatment testing will be performed immediately after the intervention with blinding between assessors and clinicians.
Following treatment and assessment, patients will be required to adhere to a questionnaire to investigate whether they believed they received one of two treatments (sham or intervention). This will investigate the believably of the sham. The entire procedure is estimated to be 60-90 minutes.
Intervention code [1] 317408 0
Intervention code [2] 317520 0
Treatment: Devices
Comparator / control treatment
There will be two "control" groups, a sham, and a no-treatment control group.Participants in the control group will be required to lie prone for 10 minutes with recordings taken before and after using the Wagner Pain Test algometer. The sham group will receive treatment from a de-tuned Activator IV which simulates the Activator IV in look , shape , colour and sound produced. This sham however produces no-force and can be used for adequate blinding as demonstrated by previous studies (can provide citations if required)
Control group

Primary outcome [1] 323577 0
Pressure Pain Threshold (PPT) will be measured using a Wagner Pain Test algometer with a 1cm2 rubber probe.
Timepoint [1] 323577 0
Outcome measures will be assessed at baseline, immediately post intervention, and then at ten, twenty, and thirty minutes post-intervention.
Secondary outcome [1] 382255 0
Recruitment rates achieved
Timepoint [1] 382255 0
3 months from the beginning of recruitment

Key inclusion criteria
18-65 years of age
Male or female
No current chronic pain condition
Must not have received Spinal Manipulative Therapy (SMT) in the preceding 7 days
No current acute or sub-acute painful condition affecting the lumbar spine
No contraindications to SMT
Completion of Participant Checklist and Medical History Questionnaire
Minimum age
18 Years
Maximum age
65 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Any rheumatologic disease
Currently receiving anticoagulant therapy
Has taken pain-relieving medication in the previous 24 hours
Alcohol intake within the last 12 hours
Suffers a neurological condition
Previous lumbar spinal injury or spinal surgery

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
The outcome of the random number generator will be sealed in envelopes and provided to a research assistant who will allocate participants.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The participants will be divided into three groups consisting of a control group (no treatment), sham group (sham treatment) and an active intervention group (activator treatment).
A random number generator will produce a randomised list of 1s, 2s and 3s allocating participants to their respective groups.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?

The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Not yet recruiting
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 305539 0
Name [1] 305539 0
The National Institute of Chiropractic Research.
Address [1] 305539 0
3822 E. University Dr. Ste. #5
Phoenix, AZ 85034
Country [1] 305539 0
United States of America
Funding source category [2] 305541 0
Name [2] 305541 0
Murdoch University
Address [2] 305541 0
90 South St, Murdoch WA 6150
Country [2] 305541 0
Primary sponsor type
Dr Ali Zaher
Murdoch Univeristy
90 South St, Murdoch WA 6150
Secondary sponsor category [1] 305947 0
Name [1] 305947 0
Dr Jean Théroux
Address [1] 305947 0
Murdoch University
90 South St, Murdoch WA 6150
Country [1] 305947 0

Ethics approval
Ethics application status
Submitted, not yet approved
Ethics committee name [1] 305846 0
Murdoch University Human Research Ethics Committee
Ethics committee address [1] 305846 0
Chancellery Building, Room 1.006 South Street MURDOCH WA 6150
Ethics committee country [1] 305846 0
Date submitted for ethics approval [1] 305846 0
Approval date [1] 305846 0
Ethics approval number [1] 305846 0

Brief summary
In this research project we will investigate the feasibility of conducting a study on how an instrument (Activator IV) used by Chiropractors to deliver spinal manipulation affects pain sensitivity in healthy adults. The Activator IV is a spring- loaded device that delivers a rapid short thrust instead of hand-delivered spinal manipulation. The study aimed at comparing the effect of two interventions (real and sham) and no intervention (control group) on pain sensitivity, among healthy participants. The sham intervention replicates the experience of the actual instrument (Activator IV) while producing no force to the targeted spinal area. Mechanical pain sensitivity also referred to as pressure pain threshold will be recorded using a device called a digital algometer. Recordings will be taken before and after the respective interventions, as stated above.
We hypothesize that significant changes in mechanical pain sensitivity will occur after the real instrument compared to the sham and control. We also hypothesize that recruitment rates will be achieved in the timeframe outlined.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 101798 0
Dr Jean Théroux
Address 101798 0
Murdoch University
90 South St, Murdoch WA 6150
Country 101798 0
Phone 101798 0
+618 9360 7567
Fax 101798 0
Email 101798 0
Contact person for public queries
Name 101799 0
Dr Ali Zaher
Address 101799 0
Murdoch University
90 South St, Murdoch WA 6150
Country 101799 0
Phone 101799 0
+618 9360 7567
Fax 101799 0
Email 101799 0
Contact person for scientific queries
Name 101800 0
Dr Jean Théroux
Address 101800 0
Murdoch University
90 South St, Murdoch WA 6150
Country 101800 0
Phone 101800 0
+618 9360 7567
Fax 101800 0
Email 101800 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No/undecided IPD sharing reason/comment
What supporting documents are/will be available?
Informed consent form
Ethical approval
'Other' documents specified
Participant Information Letter.
How or where can supporting documents be obtained?
Type [1] 7712 0
Informed consent form
Citation [1] 7712 0
Link [1] 7712 0
Email [1] 7712 0
Other [1] 7712 0
Type [2] 7713 0
Ethical approval
Citation [2] 7713 0
Link [2] 7713 0
Email [2] 7713 0
Other [2] 7713 0
Not yet Approved (In progress) . A copy of the Ethics Approval will be uploaded once received.
Attachment [2] 7713 0
Type [3] 7714 0
Citation [3] 7714 0
Link [3] 7714 0
Email [3] 7714 0
Other [3] 7714 0
Summary results
No Results