Smart Boot Use to Measure Offloading Adherence

Improving the Science of Adherence Reinforcement and Safe Mobility in People With Diabetic Foot Ulcers Using Smart Offloading

The purpose of this study is to help people with diabetes who develop neuropathic diabetic foot ulcers (DFUs). These ulcers, or sores, if left untreated can increase the chance of amputation. Part of the treatment is to have the person wear a diabetic shoe or boot to help their foot heal. Sometimes people don't wear the boot like they are told. The investigators want to compare three different kinds of diabetic boots to see if they can help make it easier for people to wear their boots as instructed.

The investigators will look at three groups of participants: the first group will use removable offloading with reinforced education emphasizing continuous wear, including during rest and sleep, and not to remove it at any time. The second group will use removable offloading consistent with standard of care and receive education on recommended wear during walking or standing, with permission to remove the device during rest and sleep. The third group will use a smart removable offloading device that provides real-time adherence feedback via a smartwatch and smartphone, with additional personalized education informed by remotely monitored adherence data.

The investigators will also be looking at how much physical activity, like walking, the participants do. And they will compare how well participants sleep and rate their quality of life in the three different boots. The investigators think that giving participants information about how much they are wearing their boot using readily available technology will help them to follow the doctor's directions better, and help their wounds heal faster.

Study Overview

• Status: Recruiting
• Conditions: Diabetic Foot Ulcer
• Intervention / Treatment: Device: Offloading Boot

• Study Type: Interventional
• Enrollment (Estimated): 210
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Fabiola Rodriguez, MD; Phone Number: 3235162332; Email: fabiola.rodriguez@med.usc.edu
• Study Contact Backup: Name: Bijan Najafi, PHD; Phone Number: 5244677127; Email: bnajafi@mednet.ucla.edu

Study Locations

• United States
  • California
    • Downey, California, United States, 90242
      • Recruiting
      • Rancho Los Amigos National Rehabilitation Center
      • Contact: Fabiola Rodriguez, MD; Phone Number: 3235162332; Email: fabiola.rodriguez@med.usc.edu
    • Glendale, California, United States, 91208
      • Recruiting
      • Verdugo Hills Hospital of USC
      • Principal Investigator: Bijan Najafi, PHD
      • Contact: Fabiola Rodriguez; Phone Number: 3235162332; Email: fabiola.rodriguez@med.usc.edu
    • Los Angeles, California, United States, 90033
      • Recruiting
      • Keck Medical Center of USC
      • Contact: Fabiola A Rodriguez, MD; Phone Number: 3235162332; Email: fabiola.rodriguez@med.usc.edu
    • Los Angeles, California, United States, 90033
      • Recruiting
      • Clemente Clinical Research
      • Contact: Scott Mathis; Phone Number: 3233304287; Email: scott.mathis@clementeclinical.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Male or female
• ≥18 years old
• Non-infected, non-ischemic DFU requiring offloading
• Ambulatory at home with or without assistance
• Willing and able to provide written informed consent

Exclusion Criteria:

• Wound present for > 1 year
• HbA1c > 12%
• ABI of index limb < 0.6 or non-detectable Doppler, and/or patient being considered for revascularization during the course of the study
• Acute Charcot neuropathy or a major foot deformity that doesn't allow them to wear the smart boot
• Amputation proximal to the rearfoot on the affected extremity
• Any clinically significant medical or psychiatric condition
• Laboratory abnormality that would interfere with the ability to participate in the study
• Concurrently participating in exercise training
• Changes in psychotropic or sleep medication in the last 6 weeks
• Ulcer involves bone
• Ulcer not of diabetic origin
• Unable or unwilling to attend prescribed clinic visits or comply with protocol

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Group 1: Reference Group; The group 1 will receive above-standard of care intervention, which includes wearing a standard removable boot and enhanced eductaion with weekly adherence reinforcement. In this group, participants are interviewed weekly, adherence is reviewed, and education is reinforced at each visit. Participants are instructed to wear the offloading device at all times, including during rest and at night, and not to remove it at any time.	Device: Offloading Boot; Removable offloading boot in one of three configurations provided to participants
Active Comparator: Group 2: Control Group; The control group uses removable offloading and represents the standard of care. These participants receive education at baseline and are advised to wear the offloading device during walking or standing; however, they are allowed to remove it during rest and sleep.	Device: Offloading Boot; Removable offloading boot in one of three configurations provided to participants
Experimental: Group 3: SmartBoot; The SmartBoot group follows a similar protocol to the control group, but adherence to wearing offloading during weight-bearing activities is reinforced using a smartwatch. The smartwatch provides real-time reminders when participants walk without the offloading device. In addition, data from remote patient monitoring may help personalize education during weekly clinic visits conducted by the research coordinator.	Device: Offloading Boot; Removable offloading boot in one of three configurations provided to participants

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Wound healing at 12 weeks or sooner	Wound healing is defined as complete epithelialization of the target ulcer, confirmed by standardized wound assessment. Healing status is recorded as a binary outcome (yes/no) for each participant. The proportion of participants achieving wound healing by 12 weeks is compared between randomized treatment arms. Unit of Measure: %	Up to 12 weeks
Time to wound healing	Time to wound healing is defined as the number of days from randomization to confirm complete epithelialization of the target ulcer, as determined by standardized wound assessment. Unit of Measure: Days	Up to 12 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Patient acceptability	To evaluate participant acceptance of SmartBoot, the Technology Acceptance Model (TAM) questionnaire is administered. TAM is an intention-based framework widely used to assess user satisfaction and acceptance of new technologies. The questionnaire has 18 items: 9 assess perceived ease of use, 5 evaluate perceived benefits, 2 measure attitudes toward use, and 2 measure behavioral intention. Responses were rated on a 5-point Likert scale ranging from 0 (strongly disagree) to 4 (strongly agree). The average scores across all categories are normalized from 0 to 100; higher values indicate better acceptability. A score of 75 or higher is considered indicative of an acceptable level of program acceptance. Unit of Measure: unit on scale	Week 12
Participant dropout rate	Participant dropout is defined as discontinuation from the study before completion of the Week 12 visit. The dropout rate is calculated as the percentage of randomized participants who withdrew before Week 12. Unit of Measure: %	From baseline through Week 12
Adherence to offloading	The average weekly adherence to offloading is assessed using a SmartBoot adherence algorithm based on device-on time during weight-bearing activity or the patient's self-reports. The algorithm reports a normalized adherence score ranging from 1 to 10, with lower scores indicating better adherence to prescribed offloading and higher scores indicating poorer adherence. Unit of Measure: Unitless (normalized score, 1-10)	From baseline through Week 12 (summarized weekly)
Percentage of Wound Area Reduction	The percentage of wound area reduction healing will be defined as the percentage reduction in wound area relative to baseline and estimated over time using a longitudinal linear model. Wound area will be derived from standardized wound imaging acquired weekly. When weekly wound area measurements are missing, values will be estimated using linear interpolation. Absolute wound area values (cm²) will also be retained in the database for descriptive purposes. - Unit of Measure: Percent reduction in wound area per week	Percent reduction in wound area per week

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in gait speed	Gait speed (m/s) is assessed using validated wearable sensor-based measurements. Change in gait speed from baseline is calculated as the average change from baseline at each monthly follow-up assessment. A higher reduction indicates slower gait and potentially a sign of lower extremity muscle atrophy in response to offloading treatment. - Unit of Measure: m/s	Baseline and monthly up to 12 weeks or until complete wound healing, whichever occurs first
Change in body sway area	Outcome Measure Description: Postural control is assessed using validated wearable sensor-based measurements of body sway area (cm2) during quiet standing in a double-stance, eyes-open condition. Change in body sway area is calculated as the average change from baseline at each monthly follow-up assessment. A higher value can potentially be a sign of lower extremity muscle atrophy in response to offloading treatment.; Unit of Measure: cm^2	Baseline and monthly up to 12 weeks or until complete wound healing, whichever occurs first
Sleep Quality	Sleep quality is assessed using the Pittsburgh Sleep Quality Index (PSQI), which yields a global score ranging from 0 to 21, with higher scores indicating worse sleep quality. Scores greater than 5 have been used to indicate poor sleep quality and are reported here for descriptive interpretation. Unit of Measure: Unit on scale (0-21)	Baseline and monthly up to 12 weeks or until complete wound healing, whichever occurs first
Overall Health	Overall health is assessed using the PROMIS-29 Profile, which measures seven health domains (Physical Function, Anxiety, Depression, Fatigue, Sleep Disturbance, Ability to Participate in Social Roles/Activities, and Pain Interference). Results are reported as T-scores standardized to the U.S. general population (mean = 50, SD = 10). For Physical Function and Social Roles, higher scores indicate better health; for all other domains, higher scores indicate greater symptom burden. Scores of 60 or higher on symptom scales or 40 or lower on function scales reflect moderate-to-severe impairment and are reported descriptively. Unit of Measure: T-score for each of 7 domains	Baseline and monthly up to 12 weeks or until complete wound healing, whichever occurs first
Frailty (Trauma-Specific Frailty Index)	Frailty is assessed using the Trauma-Specific Frailty Index, calculated as the proportion of accumulated health deficits, with scores ranging from 0 to 1. Higher values indicate greater frailty. A value of approximately 0.25 will be used as a reference threshold for frailty and is reported descriptively. Unit of Measure: Unit on scale (0-1)	Baseline and monthly up to 12 weeks or until complete wound healing, whichever occurs first
Frailty (Fried Frailty Criteria)	Frailty status is assessed using the Fried Frailty Criteria, which classify individuals based on five components. Scores range from 0 to 5, with higher scores indicating greater frailty. Categories of robust (0), pre-frail (1-2), and frail (≥3) are reported descriptively. Unit of Measure: Unit on scale (0-5)	Baseline and monthly up to 12 weeks or until complete wound healing, whichever occurs first
Depressive symptoms	Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale (CES-D), which yields scores ranging from 0 to 60, with higher scores indicating greater symptom burden. Scores of 16 or higher will be used to indicate elevated depressive symptoms and are reported for descriptive purposes. Unit of Measure: Unit on scale (0-60)	Baseline and monthly up to 12 weeks or until complete wound healing, whichever occurs first
Mobility Assessment	Mobility is assessed using the Life-Space Questionnaire, which yields scores ranging from 0 to 120, with higher scores indicating greater mobility. Lower scores reflect more restricted life-space mobility and are reported descriptively. Scores of 60 or lower are considered restricted life-space mobility. Unit of Measure: Unit on scale (0-120)	Baseline and monthly up to 12 weeks or until complete wound healing, whichever occurs first
Fall Efficacy Score	Fear of falling is assessed using the Falls Efficacy Scale-International (FES-I), which yields scores ranging from 16 to 64, with higher scores indicating greater concern about falling. Scores of 28 or higher will be used to reflect a high concern about falling and are reported descriptively. Unit of Measure: Unit on scale (16-64)	Baseline and monthly up to 12 weeks or until complete wound healing, whichever occurs first

Collaborators and Investigators

• Sponsor: University of Southern California
• Collaborators: University of California, Los Angeles
• Investigators: Principal Investigator: David G Armstrong, DPN, MD, PhD, Professor of Surgery, Keck School of Medicine of USC

Study record dates

Study Major Dates

• Study Start (Actual): October 19, 2021
• Primary Completion (Estimated): March 31, 2026
• Study Completion (Estimated): March 31, 2026

Study Registration Dates

• First Submitted: July 1, 2020
• First Submitted That Met QC Criteria: July 1, 2020
• First Posted (Actual): July 7, 2020

Study Record Updates

• Last Update Posted (Estimated): January 16, 2026
• Last Update Submitted That Met QC Criteria: January 14, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Endocrine System Diseases; Vascular Diseases; Cardiovascular Diseases; Diabetes Mellitus; Diabetic Angiopathies; Diabetes Complications; Skin Diseases; Skin Ulcer; Leg Ulcer; Diabetic Neuropathies; Foot Ulcer; Skin and Connective Tissue Diseases; Diabetic Foot
• Other Study ID Numbers: HS-20-00526

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Individually identifiable data will be deleted or masked before being made available to individuals who are not a part of the study (research staff). Results released will be sufficiently aggregated as to make individual identification of subjects highly unlikely. When individual research subjects are identifiable using substitute unique identifiers (i.e., subject 10) the translation table will be safeguarded from release outside of the study staff.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No