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Protocol Details

Investigations of Pathophysiology of Focal Hand Dystonia

This study is NOT currently recruiting participants.

Summary | Eligibility | Citations | Contacts




Sponsoring Institute

National Institute of Neurological Disorders and Stroke (NINDS)

Recruitment Detail

Type: Completed Study; data analyses ongoing
Gender: Male & Female
Min Age: 18 Years
Max Age: 70 Years

Referral Letter Required


Population Exclusion(s)




Recruitment Keyword(s)




Investigational Drug(s)


Investigational Device(s)



Device: TMS
Device: MRI
Device: VASO Imaging

Supporting Site

National Institute of Neurological Disorders and Stroke


Little is known about the problems in brain function in focal hand dystonia (FHD) or complex regional pain syndrome (CRPS) dystonia. It is unclear why some CRPS patients develop dystonia but others do not. Researchers want to learn which area of the brain is involved in CRPS dystonia compared with FHD.


To understand why people with CRPS develop dystonia, and if these reasons are different in people with FHD.


Adults ages 18 - 70 with CRPS dystonia OR with CRPS without dystonia OR with FHD and Healthy volunteers of similar age.


Participants will be screened with physical exam, neurological exam, and medical history. They may give a urine sample and will answer questions.

Participants can have 4 - 5 outpatient visits or stay at the clinical center for approximately 5-6 days.

Participants will have MRI scans. They will lie on a table that slides in and out of a scanner that takes pictures of their brain. They will do small tasks or be asked to imagine things during the scanning.

Participants will have transcranial magnetic stimulation (TMS) sessions for a few hours, with breaks. A brief electrical current passing through a well insulated wire coil on the scalp creates a magnetic pulse. This affects brain activity. Participants may do small tasks during TMS.

Participants will have the electrical activity of their muscles measured during TMS sessions. Small sticky pads will be attached to their hands and arms.

Participants ability to feel 2 separate stimuli as different will be tested by using a weak electrical shock to their fingers. They will also be asked to feel small plastic domes with ridges, that may cause discomfort.

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Healthy research volunteers and adult patients with FHD will be eligible for the study.

-Age between 18 - 70 years.

-Able to give informed consent.

-Able to comply with all study procedures.

-Subjects must be willing to abstain from alcohol for at least 48 hours prior to the study.

-Adult patients with an established diagnosis of FHD.

-Healthy volunteers will be healthy subjects without neurological or psychiatric disorders established by history and physical/neurological examination.

-Patients receiving botulinum toxin injections will be evaluated after 3 months since their last injection.

-All participants must be able to obtain an MRI (No contraindications per MRI safety checklist) which will be part of the initial evaluation.


-Self-reported consumption of >14 alcoholic drinks/week for a man and >7 alcoholic drinks/week for a woman.

-Patients on daily chronic opioid or benzodiazepine use.

-Patients treated with anticholinergics, who are not willing and/or unable to withhold taking them for 1 week prior and for the duration of the study participation.

-Patients taking opioids and/or benzodiazepines on an as needed basis, who are not willing and/or unable to withhold taking them for 1 week or time interval equivalent to 5 half-lives (whichever is shorter) prior to study participation and for the days during study participation.

-Abnormal findings on neurological examination including cognitive impairment, except diagnosis of FHD in patients.

-History of or current brain tumor, stroke, head trauma with loss of consciousness, epilepsy or seizures.

-Past or present medical history of (a) neurological disorders, such as stroke, movement disorders (other than dystonia in the patient group), ataxias, myopathies, myasthenia gravis, demyelinating diseases, alcoholism, drug dependence; (B) ventricular arrhythmias, renal and hepatic insufficiency, vascular headache, or carcinoid syndrome.

-Subjects with Baclofen pumps and/or neuro stimulators for pain.

-Current episode of major depression or any major psychiatric illness. Note: SSRI use is not exclusionary.

-Pregnant or breastfeeding women. Aside from history obtained at the screening, pregnancy status in women with childbearing potential is also established by urine pregnancy testing no more than 24 hours before each MRI and TMS sessions.

-Subjects who have contraindications to MRI:

--You have metal in your body which would make having an MRI scan unsafe, such as pacemakers, stimulators, pumps, aneurysm clips, metallic prostheses, artificial heart valves, cochlear implants or shrapnel fragments, or if you were a welder or metal worker, since you may small metal fragments in the eye.

--You are uncomfortable in small closed spaces (you have claustrophobia) so that you would feel uncomfortable in the MRI machine.

--You are not able to lie comfortably on your back for approximately 2 hours.

-Subjects who have contra-indications for TMS

--You have a pacemaker, implanted pump, stimulator, cochlear implant or metal objects inside the eye or skull.

--You have hearing loss (assessed by participant self-report or history).

--You are pregnant

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Not Provided

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Principal Investigator

Referral Contact

For more information:

Mark Hallett, M.D.
National Institute of Neurological Disorders and Stroke (NINDS)
(301) 496-9526

Vivian S. Koo
National Institute of Neurological Disorders and Stroke (NINDS)
BG 10 RM 7D36A
(301) 435-8518

Office of Patient Recruitment
National Institutes of Health Clinical Center (CC)
Building 61, 10 Cloister Court
Bethesda, Maryland 20892
Toll Free: 1-800-411-1222
Local Phone: 301-451-4383
TTY: TTY Users Dial 7-1-1

Clinical Trials Number:


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