Use of Subtle Vibration to Improve Walking Ability by Lower Limb Amputees

Mechanically-induced Stochastic Resonance to Improve Amputee Gait

The purpose of this study is to determine if subthreshold vibration, when applied to the residual limb of a lower limb amputee through their prosthetic socket, can sufficiently enhance peripheral sensation to result in an improved ability to balance and walk.

Study Overview

• Status: Completed
• Conditions: Diabetes Complications; Amputation
• Intervention / Treatment: Device: Custom prosthetic socket with mechanical vibrators (stochastic resonance); Device: Conventional prosthetic socket (current clinical practice)

Detailed Description

One of the many complications of diabetes is the loss of sensation in the feet. This sensory deficit can negatively impact the postural stability and mobility of non-amputees, since without feedback, it is simply more difficult to stand and walk. For lower limb amputees, the problem is compounded. These patients often have difficulty with prosthetic limb placement during maneuvering tasks, exhibit dramatic increases in the movement of their center of pressure during quiet standing, and both clinical and observational gait analysis reveal significant changes in their gait pattern relative to non-amputees.

The investigators' work proposes to explore the use of a novel prosthetic intervention for diabetic lower limb amputees. The investigators hypothesize that the intervention will sufficiently enhance proprioception to result in measurably improved postural stability and locomotor function for these patients. The intervention is based on a phenomenon known as stochastic resonance, whereby the application of sub-threshold vibration enables mechano-receptors previously unable to respond to stimuli to become more susceptible to depolarization. For Veterans with neuropathic proprioceptive losses, stochastic resonance may facilitate a functional response from subtle stimuli where gross inputs were formerly required.

• Study Type: Interventional
• Enrollment (Actual): 17
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Washington
    • Seattle, Washington, United States, 98108
      • VA Puget Sound Health Care System Seattle Division, Seattle, WA

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 70 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

Amputee subjects:

• unilateral transtibial amputee of diabetic etiology,
• have been fit with a prosthesis and have used a prosthesis for at least one year,
• wear the prosthesis at least 4 hours per day,
• ambulate without upper extremity aids,
• have no history of injurious falls within the previous six months, and
• touch sensation measured by a 10 gauge Semmes-Weinstein Monofilament in the dermatomes of their residual limb.

Exclusion Criteria:

Subjects will be excluded if:

• they have a significant lower extremity pain condition, musculoskeletal disorder, or neurological deficit that interferes with their ability to pursue typical daily activities or alters their gait characteristics,
• their residual limb is ulcerated, or
• are currently using anticonvulsant medications for the treatment of neuropathic pain.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Arm 1: stochastic resonance; Mechanical stochastic resonance	Device: Custom prosthetic socket with mechanical vibrators (stochastic resonance); Application of mechanically-induced sub-threshold vibration applied to the amputee's residual limb using a custom prosthetic limb system
Other: Arm 2: current clinical practice; Current clinical practice	Device: Conventional prosthetic socket (current clinical practice); No sub-threshold vibration applied to residual limb. Amputee wears conventional prosthetic socket.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Gait variability	Self-selected walking speed (mean and standard deviation) in meters/second	Testing with and without stochastic resonance will occur within a single laboratory visit on one day

Collaborators and Investigators

• Sponsor: VA Office of Research and Development
• Collaborators: University of Texas
• Investigators: Principal Investigator: Glenn K Klute, PhD, VA Puget Sound Health Care System Seattle Division, Seattle, WA

Publications and helpful links

Helpful Links

• Click here for more information about this study: Mechanically-induced Stochastic Resonance to Improve Amputee Gait
• Click here for more information about this study: Mechanically-induced Stochastic Resonance to Improve Amputee Gait

Study record dates

Study Major Dates

• Study Start (Actual): April 1, 2007
• Primary Completion (Actual): June 25, 2018
• Study Completion (Actual): June 25, 2018

Study Registration Dates

• First Submitted: March 25, 2008
• First Submitted That Met QC Criteria: September 28, 2009
• First Posted (Estimate): September 29, 2009

Study Record Updates

• Last Update Posted (Actual): June 29, 2018
• Last Update Submitted That Met QC Criteria: June 28, 2018
• Last Verified: June 1, 2018

More Information

Terms related to this study

• Keywords: Gait; Posture; Prosthesis; Vibration; Artificial limbs
• Additional Relevant MeSH Terms: Endocrine System Diseases; Diabetes Mellitus; Diabetes Complications
• Other Study ID Numbers: A4376-R

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No