Examination of the Pathophysiologic Mechanisms of CRPS by Using QST, CPM, RIC, and Heart Rate Variability QST

Ruhr University of Bochum

Status

Completed

Conditions

Carpal Tunnel Syndrome

Neuralgia

Complex Regional Pain Syndrome

Study type

Observational

Funder types

Other

Identifiers

NCT02261012

CRPS2014

Details and patient eligibility

About

This study aims for a better understanding of the pathophysiological mechanisms of the complex regional pain syndrome (CRPS). This will be done by testing the quantitative sensory testing, the remote ischemic conditioning, the conditioned pain modulation (CPM) and the analysis of the heart-rate variability in patients with CRPS and a control-group. We hypothesize decreased conditioned pain modulation, less effects of remote ischemic conditioning and an affection of the heart-rate variability in patients with CPRS.

Full description

CRPS is an illness which (seriously) affects patients in their daily life activity. The fact that the pathophysiological mechanisms are not well understood yet makes it hard to treat these patients in the right manner.

Possible patho-mechanisms might be microvascular changes and dysfunctions of the inhibitory descending pain system. Furthermore, recent studies showed that CRPS patients have macrovascular changes and a lower blood level of NO on the affected side. This indicates a NO mediated perfusion dysfunction.

Aim of this study is to examine the pathophysiological mechanism of CRPS in relation to healthy subjects and patients with a different type of pain syndrome (carpal tunnel syndrome) on the upper limb.

The investigators try to get a better understanding of the changes in the pain inhibitory system and micro- and macrocirculating blood-systems, as well as of the autonomic system of CRPS-patients.

Enrollment

62 patients

Sex

All

Ages

18+ years old

Volunteers

Accepts Healthy Volunteers

Inclusion and exclusion criteria

CRPS-patients

Inclusion Criteria:

Unilateral pain on the upper limbs, based on a scintigraphic ensured CRPS (average pain in the last 4 weeks ≥ 3 in pain Detect)
Pain history < 1 year

Exclusion criteria:

Bilateral pain on the upper limbs
Inadequate knowledge of the german language in speaking and writing
Acute psychiatric sickness
Polyneuropathy
Any added neuropathic sickness on the not affected upper limb sight
Intolerable pain during the testing
Injuries within the tested areal
Acute injuries on the hand
Pregnancy
Missing informed consent

CTS-patients

Inclusion Criteria:

Unilateral pain on the upper limbs, based on a scintigraphic ensured CRPS (average pain in the last 4 weeks ≥ 3 in pain Detect)
Pain history < 1 year

Exclusion criteria:

Bilateral pain on the upper limbs
Inadequate knowledge of the german language in speaking and writing
Acute psychiatric sickness
Polyneuropathy
Any added neuropathic sickness on the not affected upper limb sight
Intolerable pain during the testing
Injuries within the tested areal
Acute injuries on the hand
Pregnancy
Missing informed consent

Healthy subjects

Inclusion Criteria:

Age > 18 years
Written consent

Exclusion criteria:

Inadequate knowledge of the german language in speaking and writing
Current pain
Pain within in the last 14 days
Any serious internistic medicin
Any chronic skin disease
Any central neural sickness
Polyneuropathy
Peripheral nerve lesion within the testing areal
Any radiculopathy with permanent pain (in the last 3 months)
Any psychiatric sickness
Migraine ( at least one attack in the last 24 h)
Repeating headache (in the last 3 month on >5 days/month)
Taking any analgesics in the last 14 days
Taking triptans in the last 24 months
Taking any psychotropic's in the last 3 months
Any repeated taking of medication, including amber or different psychostimulants (excluding contraceptives)
Taking of any prescription and non-prescription drugs (except contraceptives) in the last 7 days or 5 half-life periods(which is always longer) before including into the study
Achilles reflex absent or within in the side-difference pathologic hypoactive or hyperactive
pallaesthesia <5/8 (<4/8 at >60 years) on the internal malleolus on both sides
abuse of alcohol or medications/drugs (corresponding to the DSM IV criteria)
joining a medical study <30 days before inclusion into the current study
jet lag, irregular work schedule, sleep deprivation within the last 3 days
change of intestity during physical activity, e.g. beginning an activity in the last weeks before inclusion into the current study