Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12614000563662
Ethics application status
Approved
Date submitted
20/05/2014
Date registered
27/05/2014
Date last updated
3/11/2016
Type of registration
Prospectively registered

Titles & IDs
Public title
Does temporarily altering visual perception of limb size have a modulatory effect on deep pain perception?
Scientific title
Does temporarily altering visual perception of limb size have a modulatory effect on deep pain perception? A repeated-measures randomised trial of normal subjects.
Secondary ID [1] 284614 0
Nil Known
Universal Trial Number (UTN)
U1111-1156-9036
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Experimental Deep tissue pain 291919 0
Condition category
Condition code
Musculoskeletal 292273 292273 0 0
Other muscular and skeletal disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Arm 1: Participant observes the quadriceps muscle during quadriceps muscle contraction
Arm 2: Participant observes the quadriceps muscle through magnifying lenses during quadriceps muscle contraction
Arm 3: Participant observes the contralateral thigh during quadriceps muscle contraction
Arm 4: Participant observes a neutral object during quadriceps muscle contraction

Each contraction will be held for 5 seconds and the contractions will be performed 3 times for each visual condition.

There will be a 5 minute wash-out period between each condition
Intervention code [1] 289393 0
Treatment: Other
Comparator / control treatment
Observation of a neutral object during a quadricpes muscle contraction.
Control group
Active

Outcomes
Primary outcome [1] 292144 0
Pain intensity using Visual Analogue Scale (VAS)

The experimentally-induced deep tissue pain will be induced by inducing DOMS in our subject's quadricep's muscles. This will be done at the first session, 48 hours prior to the testing session. DOMS will be achieved by taking the subjects through a specific protocol involving several repetitions of eccentric contractions of the quadricpes muscle.
Timepoint [1] 292144 0
Immediately post-intervention
Secondary outcome [1] 308284 0
Subjects estimated the effect of the glasses using a nine-point scale from -4 (extremely shrunken) to 4 (extremely enlarged) where 0 reflects no perceived change in the mid-thigh width.
Timepoint [1] 308284 0
This amendment was made prior to commencing data collection. The subjects were asked to rate the degree of magnification they perceived prior to removing the glasses, and immediately after testing, in the magnified condition only. The other 3 conditions did not involve attempts to magnify the preceived view of the mid-thigh and thus this scale was not assessed following testing.

Eligibility
Key inclusion criteria
Proficiency in written and spoken English
Able to provide informed written consent
Minimum age
18 Years
Maximum age
50 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Leg pain that has required a visit a health care professional in the previous 12 months.
Fractures or dislocations in the leg within the last 5 years.
Any neurological disorder.
Ongoing lumbar spine problems.
Abnormal tenderness to palpation of the soft tissues of the thigh.
Reduced or excessive knee or hip movement.
Regular consumption of anticoagulant medication or medications known to influence pain sensitivity (e.g. Painkillers, anti-inflammatories, antidepressants).
Recent quadriceps strength training (previous 6 months).
Any ongoing medical problems.

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)
Potential subjects that fulfil the inclusion criteria will be given the Plain Language Statement and will need to sign the consent form. Every subject will undergo the same process to induce DOMS in their non-dominant quadriceps muscle. They will then be required to return 48 hours later and will need to score >3 on a validated modified Likert scale to be included in the study. The scale reflects the current level of pain experienced in the quadriceps muscle.If included in the study, each subject will undergo the muscle testing procedures under all 4 visual conditions. A five minute washout period will be used between each condition At the time of determining whether the subject has sufficient DOMS to continue the study, the researcher will not know the order of visual conditions that the next subject will be exposed to, should s/he be accepted. Allocation concealment will be ensured by randomising the sequence of visual conditions. This randomisation will be computer generated by an independent person and will be counter balanced.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The randomisation sequence will be computer generated by an independent person; randomisation will be concealed and counter balanced.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Crossover
Other design features
Randomised, crossover, repeated-measures controlled experiment.
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Carry-over and cross-over effects will be explored. Primary analysis will compare pain intensity scores across the 4 conditions.

The number of participants has been extimated to be approximately 30, however the final numbers for the study will be calculated after performance of the pilot study. From the pilot study we will be able to determine the standard error of measurement (using the ICC as the reliability measure), which will be used as the minimal detectable difference, as well as data on the within subject correlation of scores. These data will inform a power calculation to arrive at the final sample size. A statistician will be consulted in calculating the final sample size.

Prior to this research study, a pilot study, involving 10 subjects, will be undertaken to ensure the stability of the intensity of DOMS over a period of 1 hour, so that any changes recorded in intensity of DOMS during the research study may not be attributed to the factor of time. Forty-eight hours after the induction of DOMS, using the same protocol as the research study, subjects will repeat the 4 identical muscle contraction tests separated by a 15 minute washout period. The conditions will replicate the process described except that the same visualisation condition will be used across all 4 conditions. Data from this pilot will also inform the power calculation for the final study.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
1/06/2015
Actual
3/08/2015
Date of last participant enrolment
Anticipated
Actual
26/11/2015
Date of last data collection
Anticipated
Actual
27/11/2015
Sample size
Target
20
Accrual to date
Final
20
Recruitment in Australia
Recruitment state(s)
WA

Funding & Sponsors
Funding source category [1] 289256 0
University
Name [1] 289256 0
UNDA Student Project Costs
University of Notre Dame
Country [1] 289256 0
Australia
Primary sponsor type
University
Name
University of Notre Dame
Address
19 Mouat Street, Fremantle, WA 6959
PO Box 1225, Fremantle, WA 6959
Country
Australia
Secondary sponsor category [1] 287929 0
None
Name [1] 287929 0
Address [1] 287929 0
Country [1] 287929 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 291027 0
Human Research Ethics Committee, University of Notre Dame
Ethics committee address [1] 291027 0
19 Mouat Street, Fremantle, WA 6959
PO Box 1225, Fremantle, WA 6959
Ethics committee country [1] 291027 0
Australia
Date submitted for ethics approval [1] 291027 0
31/03/2014
Approval date [1] 291027 0
08/05/2014
Ethics approval number [1] 291027 0
014036F

Summary
Brief summary
Recent work has demonstrated that non-informative visualisation of the body part (visualisation of the body part without visualisation of the stimulus) decreases our perception of pain when the stimulus is delivered to the skin. Subsequent investigations by the same group verified this finding, as well as demonstrating that the effect is greater when the body part is magnified and less when the area is minified, suggesting a relationship between body image and pain perception. This is important because there is mounting evidence of disrupted body image in people with persistent pain problems, and the degree of disruption seems to be related to the severity of the clinical condition. These results suggest that normalisation of the size of perception of the painful body part might have potential as a treatment strategy.

The mechanisms underlying the perception of superficial pain produced by noxious stimulation of the skin are thought to be distinct from those mechanisms that underlie perception of pain mediated by noxious stimulation of deep tissues. Importantly, most clinical pain states are associated with noxious input from deep tissue rather than the skin. Moreover, the one study that has investigated visual distortion in a clinical population noted an effect opposite to those noted above. When patients with complex regional pain syndrome performed a task with their painful upper limb, pain was less when their arm was viewed through minifying goggles and more when magnified.

While there are likely to be numerous differences in the mechanisms underpinning clinical and experimental pain, it is possible and theoretically plausible that the contrasting results were a result of the difference between superficial and the more clinically-relevant deep pain. We wish to explore this possibility by investigating the effect non-informative visualisation of the body area has on experimental deep tissue pain.
Our primary hypothesis is that visualisation of the body area will have an analgesic effect on experimentally-induced deep tissue pain. We further hypothesise that visually altering the perceived size of the body part will alter the perception of pain when compared with the baseline condition of no alteration in perceived body part size.

This research is important as it may provide insight into the role body image plays in influencing deep tissue pain as well as suggesting possible management strategies for pain problems.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 48466 0
A/Prof Benedict Wand
Address 48466 0
University of Notre Dame
19 Mouat Street, Fremantle, WA 6959
Country 48466 0
Australia
Phone 48466 0
+61 894330203
Fax 48466 0
Email 48466 0
[email protected]
Contact person for public queries
Name 48467 0
Mrs Megan van Selm
Address 48467 0
University of Notre Dame
19 Mouat Street, Fremantle, WA 6959
Country 48467 0
Australia
Phone 48467 0
+61894330009
Fax 48467 0
Email 48467 0
[email protected]
Contact person for scientific queries
Name 48468 0
Mrs Megan van Selm
Address 48468 0
University of Notre Dame
19 Mouat Street, Fremantle, WA 6959
Country 48468 0
Australia
Phone 48468 0
+61 894330009
Fax 48468 0
Email 48468 0
[email protected]

No information has been provided regarding IPD availability


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
SourceTitleYear of PublicationDOI
EmbaseVisually induced analgesia in a deep tissue experimental pain model: A randomised crossover experiment.2018https://dx.doi.org/10.1002/ejp.1234
N.B. These documents automatically identified may not have been verified by the study sponsor.