Pathophysiology of Post Amputation Pain
18 Years
N/A
Both
Amputation Stumps, Neuroma
Trial Information
Pathophysiology of Post Amputation Pain
Your participation in this study will last for 5 weeks and you will be asked to come to a
total of 3 visits. The first visit will be during the first week of the study, the second
visit during the second week of the study and the third (final) visit will be during the
fifth (and final) week of the study. For your first visit you will have a physical
examination with some sensory stimulation tests (such as vibration and pinprick tests), some
questionnaires about your health and pain history, hot and cold sensory tests, and we will
take thermal pictures of your body before and after receiving a quick electrical stimulus.
You will also be trained on how to use the finger-span device to rate your pain during the
second visit, and how to use an electronic pain diary to record your pain scores three times
a day during the five weeks of the study.
The second visit will begin with questionnaires from the first visit and thermal images with
a quick electrical stimulus. You will then be brought to an fMRI scanner room at
Northwestern University. For an hour and fifteen minutes we will take pictures of your
brain and these pictures will help us understand the changes in your brain relating to pain.
You will then be put into one of four treatment groups randomly.
The study treatment that you will get will be decided randomly or by chance, like flipping a
coin. Injections in this study will use the local anesthetic bupivacaine (a long lasting
drug like the numbing agent novocaine used by dentists). This drug causes numbness, blocks
pain and other nerve function near the injection site for 6-8 hours. Group 1 will get a
sympathetic nerve block of bupivacaine, which changes how your nerves transmit pain, in
either the neck or lower back (depending on where the amputation is located), Group 2 will
get a placebo injection (no active medicine) in either the neck or lower back (depending on
where the amputation is located), Group 3 will get a neuroma injection of bupivacaine (a
neuroma is a group of nerves at the end of your residual limb), and Group 4 will get a
placebo injection (no active medicine) at the neuroma. Some people get the bupivacaine
injection and some people get the placebo injection so that we can compare the groups and
see if the bupivacaine brings more, less or the same pain relief as a placebo injection. We
scan your brain before the injection so that we can see how your brain responds to pain. We
also scan your brain after the injection so that we can see if your brain responds
differently to pain after the injection has been done.
You will know the location of your injection before you receive the treatment (neck, lower
back or neuroma on your affected limb), but you will not know if you are getting a pain
medication injection or placebo injection. Only the study doctors will know this
information, and it can be told to you in case of an emergency. After the injection, you
will have a second hour of brain scanning. After the scanning, you will be asked to complete
some questionnaires, sensory tests, hot and cold temperature testing and we will take
thermal pictures of your body before and after a quick electrical stimulus.
Your third visit will be four weeks after your second visit. For your third visit you will
have the same questionnaires as during the first and second visits, sensory tests, hot and
cold temperature testing and we will take thermal pictures of your body before and after a
quick electrical stimulus.
Inclusion Criteria:
1. At least 18 years old
2. Able to read and speak English and provide informed consent
3. Single Amputation, upper or lower.
4. Subject has chronic post amputation pain lasting longer than three months
5. Subject has healed amputation wounds
6. Pain must be ≥3 on a scale of 0-10, 0 being no pain, 10 being the worse pain
imaginable.
7. If subjects pain is non-existent during fMRI scans, the subject needs to be willing
to have their pain induced by targeting pain trigger points (for example, study's
postdoctoral fellow would massage certain regions of the affected limb to trigger
PAP).
8. Subject agrees to 1) Stop taking all aspirin seven days prior to their second visit
(Bayer,Ecotrin,Alka Seltzer, etc.) 2) All inflammatory medications 48 hours prior to
their second visit (Advil, Motrin, Indocin, Lodine , Ibuprofen, Aleve, Naproxen, etc.
3) Supplements such as Vitamin E and Fish Oil 48 hours prior to their second visit.
9. Subject agrees to continue other prescribed medications.
10. Subject is willing to have hypodermic needle injections and images taken of them
(digital, thermal, and fMRI).
11. Able to understand and comply with all data collection methodology including
electronic diary.
12. If female, is not pregnant and not currently attempting to conceive; if of
childbearing potential, use of a highly effective method of birth control (as
determined by Pl).
Exclusion Criteria:
1. Subject is allergic to Isovue 300 or amide-type local anesthetics such as
bupivicaine, lidocaine, or mepivacaine.
2. Subject has a diagnosis of bleeding diathesis or an immune compromise.
3. Subject has pain that is more severe than their post amputation pain.
4. Subject has a clinical diagnosis of fibromyalgia.
5. Subject has metal shavings and or is frequently in an environment where there is
metal work being done or significant amounts of metal shavings.
6. Subject has ferrous metal implants, aneurism clips, bioelectric devices, and other
implants which can be affected by the magnetic field of the MRI.
7. Subject is claustrophobic.
8. Subject weighs more than 300 pounds.
9. Subject plans to start new pain treatments or therapies during the study (e.g. new
pain medication, injections, PT, surgery).
Type of Study:
Interventional
Study Design:
Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Single Group Assignment, Masking: Single Blind (Subject), Primary Purpose: Treatment
Outcome Measure:
Change in Electronic Pain Diary Ratings
Outcome Description:
A time series analysis will be utilized to compare the change in pain diary 0-10 numeric ratings before and after the injection.
Outcome Time Frame:
Ratings 3 times a day for 5 weeks
Safety Issue:
No
Principal Investigator
Norman Harden, M.D.
Investigator Role:
Principal Investigator
Investigator Affiliation:
Rehabilitation Institute of Chicago
Authority:
United States: Institutional Review Board
Study ID:
DOD_PAP 12
NCT ID:
NCT01632709
Start Date:
May 2012
Completion Date:
October 2014
Related Keywords:
- Amputation Stumps
- Neuroma
- Neuroma
Name | Location |
|---|---|
| Rehabilitation Institute of Chicago | Chicago, Illinois 60611 |
