Novel Offloading for Diabetic Foot Ulcers With PulseFlow: A Prospective Study

Study Overview
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Brief Summary
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Diabetic foot ulceration (DFU) is a common and largely preventable complication of diabetes. While most of these ulcers can be treated successfully, some will persist and become infected. Ultimately, nearly one fifth of patients with infected lower-extremity diabetic ulcers will require amputation of the affected limb, resulting in staggering costs for both the patient and the healthcare system. Prevention by identifying people at higher risk is key for better clinical management of such patients. It is not uncommon for patients suffering from diabetes to have concomitant lower extremity edema or venous insufficiency and they subsequently may benefit from graduated compression. However, because of the common association of peripheral arterial disease (PAD) in patients with diabetes, most clinicians are reluctant to apply compressive dressings in fear of exacerbating the symptoms of PAD and possibility of gangrene. A novel low voltage, battery powered medical device, PulseFlow DF® (The Diabetic Boot Company, Ltd. UK) has endeavored to assist in the treatment of Diabetic Foot Ulcers. The device provides hybrid functionality i.e. mobile air bladder pump at plantar arch and offloading boot. The air bladder inflates to 160 mmHg for approx. 1 second then deflates back to atmospheric pressure, allowing the plantar vessels sufficient time to refill. The offloading boot design holds the foot and lower leg in a position that reduces shear and friction forces and provides a reduction in plantar pressure. The PulseFlow DF is designed to record how many hours of blood pumping it has delivered. This data will be downloaded at each clinic visit. The boot cannot pump blood around the participant's foot unless fitted correctly and the battery is charged up overnight. The purpose of this study is to conduct an interventional study study with N=15 diabetic subjects with active foot ulcers to assess whether PulseFlow foot compression device can help improve lower extremity perfusion, whilst improving balance and spatio-temporal parameters of gait. The key goals of the proposed project are to test whether a specially designed compression device can improve lower extremity perfusion, whilst also simultaneously improving the balance and walking performance. Investigators envision the use of this specially designed offloading device with compression capability will help reduce the incidence of diabetic foot ulcers in high-risk diabetic patients. In addition, investigators assumed the proposed device might enhance daily physical activity as well as walking performance. Investigators will conduct a prospective clinical study to validate these hypotheses. Potential changes in walking and spontaneous daily physical activities will be assessed using validated technologies that include walking analyzer system, balance assessment using body worn sensors, and computerized pressure insoles.

Conditions
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Diabetic Foot Ulcer, Offloading

Intervention / Treatment
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* Device: Offloading boot: PulseFlow


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18- 80 years old type II diabetes with active plantar ulcer, Exclusion Criteria: Non-ambulatory or unable to stand without help or walk a distance of at least 6 feet without assistance Plantar ulcer on arch of the foot Patients with PAD (Ankle Brachial Index < 0.5) Acute foot fracture Heart failure Pregnant women Patients on immunosuppressive drugs Participation in an interventional study in the last 30 days Major amputation Patients unable or unwilling to participate in all procedures and follow-up evaluations.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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: Supportive Care
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: PulseFlow group<br>Eligible subjects will try a new offloading boot for 4 weeks | Device: Offloading boot: PulseFlow<br>* A new offloading boot, which may enhance balance, gait, and lower extremity blood flow<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Lower Extremity Perfusion Change From Baseline to 4 Weeks | Skin perfusion measured in the ankle using Sensilase device. To measure Skin Perfusion Pressure (SPP), a pressure cuff is first automatically inflated to occlude arterial bed blood flow; this is verified by PAD-IQ by determining when perfusion has stopped. The pressure is then automatically released at a controlled rate while the cuff pressure and skin perfusion are measured. A graph displays pressure and perfusion during cuff deflation and indicates the pressure at which skin perfusion is found to return. | baseline and 4 weeks | 
| Gait Speed Difference Between Pulseflow Offflaoding and Standard Offloading | the quality of walking while wearing Pulseflow offflaoding compared to standard offloading | baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Adherence | adherence to wear offloading boot by downloading from the study device to a specific developed software. The measure is the mean number of minutes the offloading boot was worn for over the course of 4 weeks | 4 weeks | 
| Wound Size Change From Baseline to 4 Weeks. | measuring the size of the wound (W, L,H) | baselineand and 4 weeks | 
| Stride Length Difference Between Pulseflow Offflaoding and Standard Offloading | the quality of walking while wearing Pulseflow offflaoding compared to standard offloading | baseline | 
| Limp Difference Between Pulseflow Offflaoding and Standard Offloading | Limp: the difference in stance percent between right and left feet | baseline | 
| Peak Swing Angular Velocity | Angular Velocity of leg swing during walking for each side | baseline | 
| Ratio of Propulsion Time to Stance Time | Propulsion time and stance time for each stride is caulcated by wearable sensors. The measure is ratio of propulsion time to stance time as percentage value. | baseline | 
| Center of Mass Sway While Wearing Standard Offloading Boot | Center of Mass (COM) sway measured by wearable inertial sensors | baseline | 
| Center of Mass Sway While Wearing Pulseflow Offloading | center of mass sway measured by a wearable inertial sensor | baseline | 
| Peak Forefoot Pressure |  | baseline |