Neuromuscular Electrical Stimulation Following Total Hip Arthroplasty

Study Overview
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Brief Summary
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Patients post total hip arthroplasty (THA) remain at high risk of developing Deep Vein Thrombosis (DVT) during the recovery period following surgery despite the availability of effective pharmacological and mechanical prophylactic methods. The use of calf muscle neuromuscular electrical stimulation (NMES) during the hospitalised recovery period on this patient group may be effective at preventing DVT. However, the haemodynamic effectiveness and comfort characteristics of NMES in post-THA patients immediately following surgery have yet to be established. The main objectives are: To establish if patients in the early post-operative period have tolerance for NMES. To determine if applying NMES to patients immediately post-THA increases venous outflow from the lower limb over resting conditions.

Official Title
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Haemodynamic Performance of Neuromuscular Electrical Stimulation (NMES) During Recovery From Total Hip Arthroplasty

Conditions
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Deep Vein Thrombosis, Total Hip Arthroplasty

Intervention / Treatment
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* Device: Neuromuscular Electrical Stimulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients who underwent total hip arthroplasty the previous day Exclusion Criteria: Patients with Diabetes Mellitus Patients with Peripheral Vascular Disease Patients currently involved in another trial Previous diagnosis of DVT

Ages Eligible for Study
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Minimum Age: 30 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: NMES<br>Application of neuromuscular electrical stimulation to the calf muscles of the patient in order to elicit contraction of the calf muscle pump and thus, eject venous blood proximally. | Device: Neuromuscular Electrical Stimulation<br>* Applied using a custom built, medically approved stimulator called the Duo-STIM. NMES to be applied to the calf muscles to elicit a muscular contraction to eject blood through the venous system.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Lower limb haemodynamic performance | Duplex Doppler ultrasound will be used as the outcome measure. Both legs will be measured for hemodynamic performance in the popliteal vein by placing the probe at the popliteal fossa. Measurements of peak venous velocity (cm/s), popliteal vein diameter (cm), time averaged mean velocity (TAMEAN, cm/s) and volume flow (ml/min) will be recorded. Doppler measurements will be taken initially at rest, before the application of NMES and once again when the NMES session had commenced. | 4 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patient comfort during application of NMES | Measurements will be taken at 3 time points (before application of NMES, after application of NMES had begun and at the end of the protocol). The measurement consists of asking patients to mark their level of comfort using a 100mm, non-hatched visual-analogue-scale (VAS). A VAS of 30 mm or less will be categorised as mild pain, between 31 and 69mm as moderate pain and scores of 70mm or greater as severe pain. | 4 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Neuromuscular electrical stimulation, NMES, Deep vein thrombosis, DVT, total hip arthroplasty, lower limb hemodynamics