Correlation Between 3 Phase Bone Scintigraphy and Pressure Pain Thresholds in Patients With Complex Regional Pain Syndrome (CRPS)

Study Overview
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Brief Summary
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The aim of the study is to investigate the correlation between increased bone metabolism in the 3 phase bone scintigraphy (TPBS) and decreased pressure pain thresholds in patients with complex regional pain syndrome (CRPS) of the upper limb and a non-CRPS-group. The investigators assume that there will be a significant correlation between the investigated values in the CRPS-group whereas the non-CRPS-group shows no significant correlation.

Detailed Description
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Pressure pain of the distal hand joints is a predominant symptom of CRPS. But so far, the diagnostic value of pressure pain in the diagnosis of CRPS has not been investigated. We compared the pressure pain thresholds of the carpus, metacarpophalangeal and proximal interphalangeal joints to a region of interest-based (ROI) analysis of a TBPS in patients with CRPS and patients with limb pain of other origin (non-CRPS-group).Additionally, the PPTs were established for a healthy control group to get reference data.

Official Title
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Correlation Between 3 Phase Bone Scintigraphy and Pressure Pain Thresholds in Patients With CRPS

Conditions
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Complex Regional Pain Syndrome Type I of the Upper Limb, Unilateral Limb Pain of Other Origin, Healthy Subjects

Intervention / Treatment
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* Procedure: Pressure Pain measurement


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: every participant: aged > 18 years with written informed consent adequate understanding of the german language indication for a TPBS independent of the study Patients with CRPS: patients with CRPS type 1 of the upper limb diagnosed on the basis of the budapest criteria (Harden, Bruehl et al., 2010) unilateral pain Control group: patients with pain of the upper limbs of other origin than CRPS who underwent a TPBS unilateral pain Healthy subjects: checked by the DFNS IMI questionnaire Exclusion Criteria: missing informed consent inadequate understanding of the german language disease duration of more than 12 months other disease of the upper extremity (e.g. polyarthrosis, rheumatoid arthritis) pregnancy/ lactation period

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients with CRPS<br>18 patients with unilateral CPRS of the upper limb were included to the study | Procedure: Pressure Pain measurement<br>* The pressure pain thresholds were established using a manual pressure algometer. The investigated joints were the carpus, the metacarpophalangeal and the proximal interphalangeal joints<br>* Other names: SOMEDIC Production AB, Sweden, Algometer Type II;|
| Patients with limb pain of other origin<br>17 patients with unilateral upper limb pain of other origin served as control group | Procedure: Pressure Pain measurement<br>* The pressure pain thresholds were established using a manual pressure algometer. The investigated joints were the carpus, the metacarpophalangeal and the proximal interphalangeal joints<br>* Other names: SOMEDIC Production AB, Sweden, Algometer Type II;|
| Healthy subjects<br>18 healthy subjects were included to establish reference data for the pressure pain thresholds | Procedure: Pressure Pain measurement<br>* The pressure pain thresholds were established using a manual pressure algometer. The investigated joints were the carpus, the metacarpophalangeal and the proximal interphalangeal joints<br>* Other names: SOMEDIC Production AB, Sweden, Algometer Type II;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Decrease of the pressure pain thresholds of the distal hand joints | The pressure pain thresholds (PPT) were mesured for the carpus, metacarpophalangeal and proximal interphalangeal joints of both hands. The mean of three determined measurements of each joint was taken as the final value. Subseqently the PPT were compared to the results of the 3 phase bone scintigraphy and the reference data of the healthy subjects. | half an hour | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Increased bone metabolism in the 3 phase bone scintigraphy | All Patients with CRPS and limb pain of other origin underwented a 3 phase bone scitigraphy to investigate a possible increased bone metabolism. Phase one and two were recorded within the first five minutes after injection of approximately 500-700 MBq 99mTechnetium-labeled methylene diphosphonate. The third phase was obtained two to three hours after injection. | 3 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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CRPS, TPBS, Pressure pain thresholds, limb pain of other origin