Distorted; Balance, Neuropathy, Peripheral Neuropathy, Sensation Disorders
Conditions
Brief summary
The overall goal of this project is to continue development and commercialization of a Wearable Sensory Prosthesis termed Walkasins. The device measures foot pressure through a thin sole insert, developed under National Institute on Aging (NIA) Small Business Innovation Research (SBIR) Phase I funding, and displays pressure information through a vibrotactile feedback array, placed around the lower leg, to help improve balance function. The device can replace lost foot pressure sensation in individuals with peripheral neuropathy who have balance problems.
Detailed description
Our specific aims are to: 1. Revise and finalize design of Walkasins® based on accomplishments, user input, as well as reviewer criticism from our Phase 1 grant and manufacture 200 units of the device for clinical testing. Milestone 1: 200 units manufactured and ready for clinical testing under Aim 2. This goal is accomplished. 2. Investigate effects of using Walkasins on clinical outcomes related to gait, balance function and associated fall risk in a population of patients with sensory peripheral neuropathy and balance problems. Hypotheses 1A-B: Patients who are trained to use Walkasins programmed to display relevant balance cues will attain higher gait speed and Functional Gait Assessment when compared to a matched cohort not using Walkasins. Milestone 2: Data collection to assess clinical utility and safety of the Walkasins on patients briefly trained to use the device has been completed.
Interventions
DEVICEWalkasins ON
Subjects will be wearing a device that works as intended and provides real-time vibrotactile feedback that reflects center of pressure sway.
DEVICEWalkasins OFF
Subjects will be wearing a device that is turned off.
Sponsors
National Institute on Aging (NIA)
RxFunction Inc.
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Healthy volunteers
No
Inclusion criteria
* Patients of any age diagnosed with Peripheral Neuropathy and who experience balance problems. * Ability to perceive the Walkasins vibration feedback, understand and physically act on the vibration feedback.
Exclusion criteria
* Vibration to the skin is contraindicated by physician * Use of ankle foot orthotic that prevents attachment of Walkasins device * Foot size smaller than Woman's 5 or larger than Men's 13
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Functional Gait Assessment (FGA) | During one test session < 3 hours | The Functional Gait Assessment (FGA) is a reliable and valid measure of gait function related to postural stability and has been shown to be effective in classifying fall risk in older adults and predicting unexplained falls in community-dwelling older adults (Wrisley, Marchetti et al. 2004; Wrisley and Kumar 2010). It has also been validated in stroke survivors (Lin, Hsu et al. 2010) and patients with Parkinson's disease (Leddy, Crowner et al. 2011) and has less flooring and ceiling effect than the Dynamic Gait Index (Lin, Hsu et al. 2010). The FGA includes a 10-item scale; each item is scored from 0 to 3 (3=normal, 2=mild impairment, 1=moderate impairment, 0=severe impairment). The maximum score is 30; minimum score, 0. Higher scores represent a better outcome. To be included in the count of participants, subjects' FGA scores needed to improve more than 4 points, which is the Minimally Clinically Important Difference (MCID) (Beninato et al. 2014). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Four-Stage Balance Test >30s | The assessment requires holding each stance for 10 seconds for a total of 40 seconds to pass. | The 4-Stage Balance Test is part of the STEADI protocol recommended by the Centers for Disease Control and Prevention (CDC) to assess fall-risk in elderly individuals. It includes four gradually more challenging postures the subject performs; 1) Stand with feet side by side; 2) Stand with feet in semi-tandem stance; 3) Stand with feet in tandem stance; 4) Stand on one leg. Subjects pass if they can hold the stance for 10 seconds and then move on to the next stance. A fail during tasks 1, 2, or 3 indicates a high risk of falling, i.e., a total performance time of less than 30 seconds. |
| 10-Meter (10M) Walk Test (Measure of Gait Speed)--Number of Participants With Improvement to Normal Gait Speed | During one test session < 3 hours | The 10m-walk is routinely done in rehabilitation and has excellent reliability in chronic stroke patients. In addition, gait speed has been found to be an important predictor of survival in older adults (Hardy, Perera et al. 2006), further emphasizing its importance as a clinical outcomes measure. Gait speed (10-meter walk, timing only the middle 6 meters to allow for acceleration and deceleration) was assessed by instructing subjects to walk at their normal speed. A difference of 0.10m/sec is defined as the Minimally Clinical Important Difference (MCID) (Perera, Mody et al. 2006). Lower scores (# of seconds) on this measure indicate a better outcome. To be included in the count of participants, subjects' times on the 10M Walk Test needed to improve by more than 0.10m/sec, the MCID. |
| Activities-Specific Balance Confidence Scale (ABC) | Measure was administered only at baseline during one test session <3 hours. | Powell and Myers (1995) developed the Activities-specific Balance Confidence (ABC) Scale to detect levels of balance confidence in elderly persons. The ABC scale is a one-page questionnaire that asks questions about balance confidence when performing 16 different tasks. The items are rated on a scale of 0 to 100; a score of 0 indicates no confidence and a score of 100 indicates complete confidence when performing the task. The overall score is calculated by adding the individual items then dividing by the total number of items (16). The higher the score, the greater the person's balance confidence; thus, higher scores indicate that subjects are more confident of their balance. The ABC Scale was assessed only at baseline to document the level of balance confidence the subjects had before beginning the study intervention. |
Participant flow
Recruitment details
Thirty-one male community-dwelling veterans, ages 56-84, who experienced sensory peripheral neuropathy and balance problems, participated in the trial.
Participants by arm
| Arm | Count |
|---|---|
| Walkasins On Group A subjects first wore Walkasins and received real-time vibrotactile feedback that reflects real changes in center of pressure sway. Following a 1-hour rest period, they were retested with Walkasins turned off.
The results for the Walkasins On state include all subjects, combining Group A, who were randomized to initially be tested with Walkasins turned on and then retested with walkasins turned off, and Group B, who were randomized to initially be tested with Walkasins turned off and then retested with Walkasins turned on. | 15 |
| Walkasins Off Group B subjects first wore Walkasins turned off and not receive any vibrotactile feedback. Following a 1-hour rest period, they were retested with Walkasins turned on.
The results for the Walkasins Off state include all subjects, combining Group A, who were randomized to initially be tested with Walkasins turned on and then retested with walkasins turned off, and Group B, who were randomized to initially be tested with Walkasins turned off and then retested with Walkasins turned on. | 16 |
| Total | 31 |
Baseline characteristics
| Characteristic | Walkasins On | Walkasins Off | Total |
|---|---|---|---|
| Age, Continuous | 71.6 years STANDARD_DEVIATION 7.1 | 71.6 years STANDARD_DEVIATION 6.2 | 71.6 years STANDARD_DEVIATION 6.65 |
| Functional Gait Assessment (FGA) Score | 15.0 units on a scale STANDARD_DEVIATION 4.5 | 15.4 units on a scale STANDARD_DEVIATION 5.2 | 15.2 units on a scale STANDARD_DEVIATION 4.9 |
| Race and Ethnicity Not Collected | — | — | 0 Participants |
| Region of Enrollment United States | 15 participants | 16 participants | 31 participants |
| Sex: Female, Male Female | 0 Participants | 0 Participants | 0 Participants |
| Sex: Female, Male Male | 15 Participants | 16 Participants | 31 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 15 | 0 / 16 |
| other Total, other adverse events | 0 / 15 | 0 / 16 |
| serious Total, serious adverse events | 0 / 15 | 0 / 16 |
Outcome results
Primary
Functional Gait Assessment (FGA)
The Functional Gait Assessment (FGA) is a reliable and valid measure of gait function related to postural stability and has been shown to be effective in classifying fall risk in older adults and predicting unexplained falls in community-dwelling older adults (Wrisley, Marchetti et al. 2004; Wrisley and Kumar 2010). It has also been validated in stroke survivors (Lin, Hsu et al. 2010) and patients with Parkinson's disease (Leddy, Crowner et al. 2011) and has less flooring and ceiling effect than the Dynamic Gait Index (Lin, Hsu et al. 2010). The FGA includes a 10-item scale; each item is scored from 0 to 3 (3=normal, 2=mild impairment, 1=moderate impairment, 0=severe impairment). The maximum score is 30; minimum score, 0. Higher scores represent a better outcome. To be included in the count of participants, subjects' FGA scores needed to improve more than 4 points, which is the Minimally Clinically Important Difference (MCID) (Beninato et al. 2014).
Time frame: During one test session < 3 hours
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Walkasins ON | Functional Gait Assessment (FGA) | 17 Participants |
| Walkasins OFF | Functional Gait Assessment (FGA) | 7 Participants |
Secondary
10-Meter (10M) Walk Test (Measure of Gait Speed)--Number of Participants With Improvement to Normal Gait Speed
The 10m-walk is routinely done in rehabilitation and has excellent reliability in chronic stroke patients. In addition, gait speed has been found to be an important predictor of survival in older adults (Hardy, Perera et al. 2006), further emphasizing its importance as a clinical outcomes measure. Gait speed (10-meter walk, timing only the middle 6 meters to allow for acceleration and deceleration) was assessed by instructing subjects to walk at their normal speed. A difference of 0.10m/sec is defined as the Minimally Clinical Important Difference (MCID) (Perera, Mody et al. 2006). Lower scores (# of seconds) on this measure indicate a better outcome. To be included in the count of participants, subjects' times on the 10M Walk Test needed to improve by more than 0.10m/sec, the MCID.
Time frame: During one test session < 3 hours
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Walkasins ON | 10-Meter (10M) Walk Test (Measure of Gait Speed)--Number of Participants With Improvement to Normal Gait Speed | 8 Participants |
| Walkasins OFF | 10-Meter (10M) Walk Test (Measure of Gait Speed)--Number of Participants With Improvement to Normal Gait Speed | 5 Participants |
Secondary
Activities-Specific Balance Confidence Scale (ABC)
Powell and Myers (1995) developed the Activities-specific Balance Confidence (ABC) Scale to detect levels of balance confidence in elderly persons. The ABC scale is a one-page questionnaire that asks questions about balance confidence when performing 16 different tasks. The items are rated on a scale of 0 to 100; a score of 0 indicates no confidence and a score of 100 indicates complete confidence when performing the task. The overall score is calculated by adding the individual items then dividing by the total number of items (16). The higher the score, the greater the person's balance confidence; thus, higher scores indicate that subjects are more confident of their balance. The ABC Scale was assessed only at baseline to document the level of balance confidence the subjects had before beginning the study intervention.
Time frame: Measure was administered only at baseline during one test session <3 hours.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Walkasins ON | Activities-Specific Balance Confidence Scale (ABC) | 59.6 score on a scale of 0-100 | Standard Deviation 19.3 |
| Walkasins OFF | Activities-Specific Balance Confidence Scale (ABC) | 64.7 score on a scale of 0-100 | Standard Deviation 17.3 |
Secondary
Four-Stage Balance Test >30s
The 4-Stage Balance Test is part of the STEADI protocol recommended by the Centers for Disease Control and Prevention (CDC) to assess fall-risk in elderly individuals. It includes four gradually more challenging postures the subject performs; 1) Stand with feet side by side; 2) Stand with feet in semi-tandem stance; 3) Stand with feet in tandem stance; 4) Stand on one leg. Subjects pass if they can hold the stance for 10 seconds and then move on to the next stance. A fail during tasks 1, 2, or 3 indicates a high risk of falling, i.e., a total performance time of less than 30 seconds.
Time frame: The assessment requires holding each stance for 10 seconds for a total of 40 seconds to pass.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Walkasins ON | Four-Stage Balance Test >30s | 27.5 number of seconds stances held | Standard Deviation 7.4 |
| Walkasins OFF | Four-Stage Balance Test >30s | 25.6 number of seconds stances held | Standard Deviation 8.3 |