ear-infrared spectroscopy in cold type Complex Regional Pain Syndrome

Recruitment & Eligibility

Status: Pending

Sex: Not specified

Target Recruitment: 64

Inclusion Criteria

In order to be eligible to participate in this study, a subject must meet all of the following criteria:
- Patients with the diagnosis cold unilateral CRPS of an upper or lower limb according to the Budapest Research Criteria (not applicable in Controls):
Continuing pain, which is disproportionate to any inciting event
Must report at least one symptom in three of the four following categories:
Sensory: reports of hyperesthesia and/or allodynia
Vasomotor: reports of temperature asymmetry and/or skin color changes and/or skin color asymmetry
Sudomotor/edema: reports of edema and/or seating changes and/or sweating asymmetry
Motor/trophic: reports of decreased range of motion and/or motor dysfunction (weakness, tremor, dystonia) and/or trophic changes (hair, nail, skin)
Must display at least one sign at time of evaluation in two or more of the following categories:
Sensory: evidence of hyperalgesia (to pinprick) and/or allodynia (to light touch and/or deep somatic pressure and/or joint movement)
Vasomotor: evidence of temperature asymmetry with the affected side being >= 1° colder than the unaffected side.
Sudomotor/edema: evidence of edema and/or sweating changes and/or sweating asymmetry
Motor/trophic: evidence of decreased range of motion and/or motor dysfunction (weakness, tremor, dystonia) and/or trophic changes (hair, nail, skin).
There is no other diagnosis that better explains the signs and symptoms.
- Age >= 18 years
- Able to provide written informed consent

Exclusion Criteria

A potential subject who meets any of the following criteria will be excluded from participation in this study:
- Known history of peripheral arterial disease (PAD) or suspicion of PAD at intake
- Known history of Diabetes Mellitus
- Other confounding neuropathic conditions i.e. paraplegia and neuropathies due to other causes than CRPS.
- Coagulopathy or use of blood thinners
- Use of vasoactive medications
- Pregnancy

Study & Design

Study Type: Observational non invasive

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
<p>The main study parameters consist of the within person and between person<br /><br>difference in muscle oxygen consumption and blood flow in patients with cold<br /><br>type CRPS and controls. These differences are tested during rest and exercise. </p><br>

Secondary Outcome Measures

Name	Time	Method
<p>Secondary study parameters will be:<br /><br>- The tissue saturation index (TSI) during rest and exercise. This is an<br /><br>estimate of the tissue oxygen saturation in percentage.<br /><br>- The rise in oxyhemoglobin during reactive hyperemia. This is measured during<br /><br>rest and exercise.</p><br>