Bone Microcirculation After Remote Ischemic Preconditioning

Study Overview
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Brief Summary
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In trauma surgery and hand surgery treatment strategies of none healing bone fractures aim at replacing pseudarthrosis by well vascularized bone and improving microcirculation. Although previous studies indicate that remote ischemic preconditioning (RIPC) can accelerate bone healing in case of non-union, only a few studies focused on the elucidation of its mechanisms of action. Therefore, the aim of this study is to evaluate the microcirculatory effects of remote ischemic preconditioning (RIPC) on scaphoid bones and metacarpal bones and metatarsal bones in a human in-vivo setting for the first time.

Official Title
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Effects of Remote Ischemic Preconditioning in Bone Microcirculation

Conditions
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Intact Scaphoid Bone, Intact Metacarpal Bone, Fractured Scaphoid Bone, Fractured Metacarpal Bone

Intervention / Treatment
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* Procedure: Remote Ischemic Preconditioning (by Blood Pressure Cuff)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Group A (n=20): Consent-capable male and female patients ≥18 years of age who have an intact scaphoid bone. Group B (n=20): Consent-capable male and female patients ≥18 years of age who have an intact metacarpal bone. Group C (n=20): Consent-capable male and female patients ≥18 years of age who have a fractured scaphoid bone. Group D (n=20): Consent-capable male and female patients ≥18 years of age who have a fractured metacarpal bone. Exclusion Criteria: below 18 years of age scar tissue above measuring focus osteoporosis or comparable bone disease medication that influences bones

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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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intact scaphoid bone<br>Group A (n=20): Consent-capable male and female patients ≥18 years of age who have an intact scaphoid bone. Intervention: Remote Ischemic Preconditioning (by Blood Pressure Cuff) | Procedure: Remote Ischemic Preconditioning (by Blood Pressure Cuff)<br>* Remote Ischemik Preconditioning is performed using a Blood Pressure Cuff with a pressure slightly above patients' blood pressure on the upper arm.<br>|
| Experimental: Intact metacarpal bone<br>Group B (n=20): Consent-capable male and female patients ≥18 years of age who have an intact metacarpal bone. Intervention: Remote Ischemic Preconditioning (by Blood Pressure Cuff) | Procedure: Remote Ischemic Preconditioning (by Blood Pressure Cuff)<br>* Remote Ischemik Preconditioning is performed using a Blood Pressure Cuff with a pressure slightly above patients' blood pressure on the upper arm.<br>|
| Experimental: Fractured scaphoid bone<br>Group C (n=20): Consent-capable male and female patients ≥18 years of age who have a fractured scaphoid bone. Intervention: Remote Ischemic Preconditioning (by Blood Pressure Cuff) | Procedure: Remote Ischemic Preconditioning (by Blood Pressure Cuff)<br>* Remote Ischemik Preconditioning is performed using a Blood Pressure Cuff with a pressure slightly above patients' blood pressure on the upper arm.<br>|
| Experimental: Fractured metacarpal bone<br>Group D (n=20): Consent-capable male and female patients ≥18 years of age who have a fractured metacarpal bone. Intervention: Remote Ischemic Preconditioning (by Blood Pressure Cuff) | Procedure: Remote Ischemic Preconditioning (by Blood Pressure Cuff)<br>* Remote Ischemik Preconditioning is performed using a Blood Pressure Cuff with a pressure slightly above patients' blood pressure on the upper arm.<br>|
| Experimental: Intact metatarsal bone<br>Group B (n=20): Consent-capable male and female patients ≥18 years of age who have an intact metatarsal bone. Intervention: Remote Ischemic Preconditioning (by Blood Pressure Cuff) | Procedure: Remote Ischemic Preconditioning (by Blood Pressure Cuff)<br>* Remote Ischemik Preconditioning is performed using a Blood Pressure Cuff with a pressure slightly above patients' blood pressure on the upper arm.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in microcirculation (composite outcome measure) | Bone blood flow [arbitrary units AU] Bone blood velocity [AU] Tissue oxygen saturation [%] Relative postcapillary venous filling pressure [AU] (Composite outcome measure) | Baseline and 1 minute post-dose |