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Trial registered on ANZCTR


Registration number
ACTRN12616001279415
Ethics application status
Approved
Date submitted
2/09/2016
Date registered
12/09/2016
Date last updated
17/08/2018
Type of registration
Prospectively registered

Titles & IDs
Public title
An experimental test of high frequency electrical stimulation of peripheral nerves for treating chronic pain
Scientific title
A double-blind test of high frequency electrical stimulation of peripheral nerves for treating chronic pain
Secondary ID [1] 290084 0
Nil
Universal Trial Number (UTN)
Trial acronym
Linked study record
ACTRN12616000971437

Health condition
Health condition(s) or problem(s) studied:
neuropathic pain 300167 0
occipital headache 300236 0
peripheral nerve injury 300237 0
Condition category
Condition code
Anaesthesiology 300056 300056 0 0
Pain management

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Clinical audit data suggests that high frequency electrical stimulation of peripheral nerves is an effective treatment for occipital headaches and chronic pain that develops after peripheral nerve injury. We now wish to investigate effects of this stimulation on pain and sensitivity to painful stimulation in patients with a stimulator implanted along or adjacent to a peripheral nerve. The implanted stimulator consists of two components: a cylindrical multi-contact electrode wire placed adjacent to a peripheral nerve and a rechargeable electrical pulse generator.
We will compare pain and sensitivity to painful stimuli (pressure, sharpness, heat, cold) after the stimulator has been switched on or off for 4 hours. As stimulation itself produces no detectable sensations, we will use a double blind strategy to investigate effects of stimulation (i.e., neither the participant nor the investigator will know whether the stimulator is switched on or off). The pressure-pain threshold will be identified by applying pressure at 100 grams/second to the skin with a pressure sensor (a Wagner Instruments algometer) until the patient reports pain or to a maximum of 5 kg. Patients will rate sharpness between 0 and 10 to the application of a calibrated pin (40 grams force, Neuropen device). Temperature ramps of 1 degree/second will be delivered by a purpose-built Peltier device until the patient reports pain or to limits of 0 and 50 degrees C. These stimuli will be administered by Professor Drummond within the region of pain and at a similar contralateral site while the stimulator is switched off at baseline and four hours after the stimulator has either been switched on or switched off. The washout period between treatments will be at least one week.
Intervention code [1] 295823 0
Treatment: Devices
Comparator / control treatment
In the control condition, the stimulator will be turned off by telemetry by a non-blinded investigator who will not be involved in data collection.
Control group
Placebo

Outcomes
Primary outcome [1] 299525 0
numerical pain rating between 0 (no pain) and 10 (extreme pain).
Timepoint [1] 299525 0
(1) at baseline after the stimulator has been switched off overnight; and (2) 4 hours after the stimulator has been switched on or remains off.
Secondary outcome [1] 327446 0
A graded increase in temperature at 1 degree C/second will be applied from a starting temperature of 32 degrees C in the distribution of pain and at a similar site on the other side of the body until the participant reports pain or to a maximum of 50 degrees C. The temperature ramp will be applied using a purpose-built Peltier device.
Timepoint [1] 327446 0
(1) at baseline after the stimulator has been switched off overnight; and (2) 4 hours after the stimulator has been switched on or remains off.
Secondary outcome [2] 327447 0
A graded decrease in temperature at 1 degree C/second will be applied from a starting temperature of 32 degrees C in the distribution of pain and at a similar site on the other side of the body until the participant reports pain or to a minimum of 0 degrees C. The temperature ramp will be applied using a purpose-built Peltier device.
Timepoint [2] 327447 0
(1) at baseline after the stimulator has been switched off overnight; and (2) 4 hours after the stimulator has been switched on or remains off..
Secondary outcome [3] 327448 0
The tactile threshold to graded nylon monofilaments (Marstock Instruments) will be assessed in the distribution of pain and at a similar site on the other side of the body.
Timepoint [3] 327448 0
(1) at baseline after the stimulator has been switched off overnight; and (2) 4 hours after the stimulator has been switched on or remains off..
Secondary outcome [4] 327449 0
A graded increase in pressure at 100 grams/second will be applied using a calibrated pressure sensor (algometer, Wagner Instruments) in the distribution of pain and at a similar site on the other side of the body until the patient reports pain or to a maximum of 5 kg.
Timepoint [4] 327449 0
(1) at baseline after the stimulator has been switched off overnight; and (2) 4 hours after the stimulator has been switched on or remains off..
Secondary outcome [5] 327450 0
Patients will rate sharpness (between 0 and 10) to a calibrated pin (Neuropen device) applied at 40 grams of pressure in the distribution of pain and at a similar site on the other side of the body
Timepoint [5] 327450 0
(1) at baseline after the stimulator has been switched off overnight; and (2) 4 hours after the stimulator has been switched on or remains off..
Secondary outcome [6] 327451 0
Skin temperature will be measured with a non-contact infrared device (Cool-Tech) in the distribution of pain and at a similar site on the other side of the body.
Timepoint [6] 327451 0
(1) at baseline after the stimulator has been switched off overnight; and (2) 4 hours after the stimulator has been switched on or remains off..

Eligibility
Key inclusion criteria
Patients who have been implanted with a high frequency electrical nerve stimulator (Nevro stimulator, ARTG Identifier 186043) approximately 2 cm from a peripheral nerve within the past two years will be invited to participate in this study. They will be informed that we wish to investigate the effect of the stimulator on pain.
Minimum age
18 Years
Maximum age
80 Years
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Patients will be excluded if they have had surgery within the past month at the site of stimulator implantation or if they have any current infection at the site of stimulator implantation or intercurrent infection.

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)
Allocation is not concealed.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The sequence will be produced by a random number generator at random.org.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis
As this is the first study of its kind, and involves a small number of eligible patients, the sample will consist of all available patients in Dr Finch's practice who were implanted with a stimulator adjacent to a peripheral nerve within the past two years. Data will be analysed with repeated measures analysis of variance to determine whether pain and sensitivity to painful stimuli differ between the "stimulator off" and "stimulator on" conditions..

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
WA

Funding & Sponsors
Funding source category [1] 294452 0
Self funded/Unfunded
Name [1] 294452 0
Dr Philip Finch
Address [1] 294452 0
Perth Pain Management Centre, 18 Hardy Street, South Perth, 6151
Country [1] 294452 0
Australia
Funding source category [2] 294502 0
University
Name [2] 294502 0
Murdoch University
Address [2] 294502 0
90 South Street, Murdoch, 6150 WA
Country [2] 294502 0
Australia
Primary sponsor type
Individual
Name
Dr Philip Finch
Address
Perth Pain Management Centre, 18 Hardy Street, South Perth, 6151
Country
Australia
Secondary sponsor category [1] 293316 0
University
Name [1] 293316 0
Murdoch University
Address [1] 293316 0
Murdoch University,
90 South Street,
Murdoch, WA 6150
Country [1] 293316 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 295884 0
Murdoch University Human Research Ethics Committee
Ethics committee address [1] 295884 0
Murdoch University,
90 South Street,
Murdoch, WA 6150
Ethics committee country [1] 295884 0
Australia
Date submitted for ethics approval [1] 295884 0
30/08/2016
Approval date [1] 295884 0
03/10/2016
Ethics approval number [1] 295884 0

Summary
Brief summary
Clinical audit data suggests that high frequency electrical stimulation of peripheral nerves is an effective treatment for occipital headaches and chronic pain that develops after peripheral nerve injury. We now wish to investigate effects of this stimulation on pain and sensitivity to painful stimulation in patients with a stimulator implanted along or adjacent to a peripheral nerve. Specifically, we will compare pain and sensitivity to painful stimuli (pressure, sharpness, heat, cold) while the stimulator is switched on and at least 4 hours after the stimulator has been switched off. As stimulation itself produces no detectable sensations, we will use a double blind strategy to investigate effects of stimulation (i.e., neither the participant nor the investigator will know whether the stimulator is switched on or off).
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 68806 0
Dr Philip Finch
Address 68806 0
Perth Pain Management Centre, 18 Hardy Street, South Perth, 6151
Country 68806 0
Australia
Phone 68806 0
+61 8 93672233
Fax 68806 0
Email 68806 0
pfinch@iinet.net.au
Contact person for public queries
Name 68807 0
Dr Philip Finch
Address 68807 0
Perth Pain Management Centre, 18 Hardy Street, South Perth, 6151
Country 68807 0
Australia
Phone 68807 0
61 8 93672233
Fax 68807 0
Email 68807 0
pfinch@iinet.net.au
Contact person for scientific queries
Name 68808 0
Dr Philip Finch
Address 68808 0
Perth Pain Management Centre, 18 Hardy Street, South Perth, 6151
Country 68808 0
Australia
Phone 68808 0
61 8 93672233
Fax 68808 0
Email 68808 0
pfinch@iinet.net.au

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary