Walking Function in Diabetic Peripheral Neuropathy

Official title

Walking Function in Individuals With Diabetic Peripheral Neuropathy: Biomechanical Mechanisms and Implications for Clinical Outcomes and Gait Retraining

Overview

The purpose of this study is to 1) examine the differences in walking function and movement patterns between individuals with diabetic peripheral neuropathy and healthy adults with no known conditions; 2) examine if receiving feedback on walking form will help change walking patterns; and 3) examine the feasibility, safety, and preliminary effects of walking training with feedback on walking function in individuals with diabetic peripheral neuropathy.

Detailed description

Over 34 million adults in the United States are living with Diabetes Mellitus (DM). Diabetic peripheral neuropathy (DPN) is the most common complication, affecting 50% of individuals with DM. Consequences of DPN include reduced sensation and feedback from the foot and lower limb and increased plantar pressures, predisposing patients to ulcers and lower extremity amputation. Individuals with DPN experience decreased quality of life compared with their healthy and non-neuropathic DM peers, and report problems with mobility, daily activities, pain, and discomfort. Additionally, people with DPN display reduced functional ambulation, step counts, and walking speed. Though increases in physical activity and functional capacity have been associated with improvements in quality of life, DPN poses a unique challenge in mitigating risk while pursuing traditional exercise and walking programs.

Traditional gait training programs used to improve walking function may increase ulceration risk, making these interventions unsuitable if not tailored for people with DPN. The goal of this study is to elucidate the underlying biomechanical mechanisms contributing to the inter-relationships between plantar pressure and propulsion in individuals with DPN, and to examine the safety and feasibility of using real-time biofeedback to modify plantar pressure and propulsion during gait.

The aims of this study are to evaluate (1) biomechanical mechanisms contributing to abnormal plantar pressure and propulsion during gait in individuals with DPN; (2) biofeedback-induced changes in plantar pressure, propulsion, and biomechanics during gait in individuals with DPN and age-similar controls; and (3) the acceptability, feasibility, safety, and preliminary effects of gait training in individuals with DPN. Insights into the biomechanical mechanisms underlying plantar pressure and propulsion in people with DPN will allow for the design of more informed and effective gait rehabilitation interventions aimed at preventing deleterious outcomes such as ulceration and amputation that can be tailored to individual patient characteristics.

Able-bodied participants will complete three experimental sessions and participants with DPN will complete a total of seven experimental sessions. Each session will be approximately 2-3 hours in duration.

Interventions

• Other Clinical Evaluation
  A clinical evaluation occurs at the first study session. The clinical evaluation assesses walking function and mobility, lower extremity, sensation, health-related quality of life (HRQoL) and foot function. Session 2 will be a dynamometer-based evaluation of passive ankle stiffness and 3-dimensional gait analysis to evaluate baseline biomechanics. During Session 3, real-time biofeedback conditions will be used to measure the immediate effects on walking function.
• Other Evaluation of Passive Ankle Stiffness
  Participants will be seated in a dynamometer with their trunk and thigh stabilized to the dynamometer chair, ankle joint aligned with the rotational axis of the dynamometer, and foot stabilized to the foot plate. EMG activity will be recorded from lower limb muscles (gastrocnemius, soleus, tibialis anterior) during all isolated contractions. Participants will first perform three maximum voluntary isometric contractions (MVIC) while seated in a dynamometer. Participants will then perform three is
• Other Gait Biomechanics
  Three-dimensional gait analysis is performed as participants walk at a self-selected speed on an instrumented treadmill. Reflective markers are attached to lower extremity segments. Elastic bands are wrapped around the thighs, calves, and pelvis to which small, thermoplastic shells containing reflective markers are attached. Additional markers are taped to the participant's shoes and on the upper back, shoulder, hip, knee, and ankle joints with adhesive skin tape. Marker data is collected using
• Other Gait Biofeedback
  Audio-visual biofeedback will be provided using a screen placed in front of the treadmill and a speaker. For plantar pressure biofeedback, a visual display of a foot with a colored heat map will represent the current plantar pressure, in addition to bar graphs representing real-time movement of plantar pressure in specific areas of the foot. A target will be provided using the heat map colors of red and target line on the bar graph. For propulsion biofeedback, a visual display with a marker will
• Other Plantar Pressure Biofeedback Gait Training
  Participants will complete a 3-dimensional gait evaluation prior to training, after a 6-minute control bout without biofeedback, and following three 6-minute biofeedback training bouts (total 18-minutes). Individualized biofeedback targets will be calculated from each participant's immediate biofeedback session to best minimize plantar pressure whilst maintaining or enhancing propulsion. Audio-visual biofeedback is provided using a screen placed in front of the treadmill and a speaker. For plant
• Other Propulsion Biofeedback Gait Training
  Participants will complete a 3-dimensional gait evaluation prior to training, after a 6-minute control bout without biofeedback, and following three 6-minute biofeedback training bouts (total 18-minutes). Individualized biofeedback targets will be calculated from each participant's immediate biofeedback session to best minimize plantar pressure whilst maintaining or enhancing propulsion. Audio-visual biofeedback is provided using a screen placed in front of the treadmill and a speaker. For propu

Primary outcome measures

• Biomechanical plantar pressure [Time frame: Study Session 2 (occurs 24 hours up to 2 weeks after Day 1)]
• Biomechanical Propulsion [Time frame: Study Session 2 (occurs 24 hours up to 2 weeks after Day 1)]
• Biomechanical modulation of ankle stiffness [Time frame: Study Session 2 (occurs 24 hours up to 2 weeks after Day 1)]

Secondary outcome measures (3)

• Changes induced by biofeedback in plantar pressure [Time frame: Study sessions 4 (48 hours - 3 weeks after session 3), 5 (24-48 hours after session 4) , 6 (3 weeks after session 5) and 7 (24-48 hours after session 6)]
• Changes induced by biofeedback in propulsion [Time frame: Study sessions 4 (48 hours - 3 weeks after session 3), 5 (24-48 hours after session 4) , 6 (3 weeks after session 5) and 7 (24-48 hours after session 6)]
• Changes induced by biofeedback in biomechanics during gait [Time frame: Study sessions 4 (48 hours - 3 weeks after session 3), 5 (24-48 hours after session 4) , 6 (3 weeks after session 5) and 7 (24-48 hours after session 6)]

Eligibility criteria

Inclusion Criteria for All Participants:

• Age 45+ years
• Able to walk 10-meters independently without an assistive device
• Sufficient cardiovascular and musculoskeletal health to walk on a treadmill for 1-minute at self-selected speed

Inclusion Criteria for Participants with DPN:

• Diagnosis of DM
• Diagnosis of DPN by a physician
• Foot examination within the past 6 months to document ambulatory status
• Physician's clearance

Exclusion Criteria for Healthy Able-Bodied Individuals:

• History of neurologic disease
• History of orthopaedic disease affecting the lower extremities
• History of injury or pain affecting the lower extremity or walking function within the past 6 months

Exclusion Criteria for All Participants:

• History of amputation
• Active ulceration
• Medial column deformity
• History of Charcot osteoarthropathy
• History of posterior muscle group lengthening
• History of lower extremity joint replacement
• History of lower extremity and/or foot surgery affecting walking mechanics
• Orthopaedic problems of the lower limbs or spine due to other medical conditions (not DM or DPN) that limit walking or cause pain during walking
• Improper footwear for walking and community ambulation
• Cardiovascular or medical condition affecting ability to walk safely
• History of unexplained dizziness or fainting in the past 2 months
• Allergy to adhesive tape or rubbing alcohol
• Individuals who are pregnant, prisoners, or not yet adults
• Inability to communicate with the investigators
• Inability to provide written informed consent

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Allocation

Randomized

Model

Crossover

Masking

Open label

Primary purpose

Basic science

Study locations

United States · 1 center

• Florida Institute for Human and Machine Cognition — Pensacola

Identifiers

NCT: NCT05965336 · IRB-2025-0002 · K01HD107294

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗