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iWalk Hands Free Crutch

Effects of a Hands Free Crutch on Walking Stability During Gait

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04978363
Acronym
HFC
Enrollment
21
Registered
2021-07-27
Start date
2021-10-05
Completion date
2022-01-27
Last updated
2023-05-22

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Healthy

Keywords

Hands Free Crutch, Crutches, Assistive devices, Balance, Walking stability, Gait analysis, Adult, Biomechanics, Walking boot

Brief summary

The proposed study evaluates the effects of a hands free crutch (iWalkFree, Inc.) on walking balance and stability compared to standard crutches. It is expected that the hands free crutch will provide better stability during walking on a level surface and better reported balance confidence compared to standard crutches. In this study, walking stability will be assessed using motion capture data from an infrared camera system with 12 mounted cameras surrounding a level walkway. Balance will be assessed through a self-reported activity-specific balance confidence (ABC) questionnaire. An improved understanding of the effects of the hands free crutch on gait may benefit the future prescription of ambulatory assistive devices. The proposed study may provide insight that can be used by physical therapists and other providers to select the ambulatory assistive device that best meets their patients' needs.

Detailed description

The purpose of this study is to compare the hands free crutch (HFC) to standard axillary crutches (SACs) with and without a walking boot, using outcomes related to walking stability, balance confidence, patient preference, device comfort, and any reported pain while using the devices. Healthy, able-bodied individuals will wear a walking boot to simulate a below knee injury or post-surgery condition during participation. They will maintain a non-weight bearing status while completing the 4 research conditions in randomized order: 1) BOOT, 2) HFC + BOOT, 3) SAC + BOOT, or 4) NONE. Participants will complete 5 total sessions, with 4 biomechanics data collection sessions corresponding to the 4 conditions. At the first visit, participants will complete pre-consent screening and consent paperwork. Then they will be randomized to the 4 conditions above, and anthropometric (body height, weight/mass, leg length, shoe length and width) and demographic data will be collected. Participants will accommodate overnight to each of the 4 study conditions before testing. If participants are randomized to the NONE condition first, they will have the option of completing testing in that condition (no Boot) at the initial visit. The primary dependent measure is whole body angular momentum, an objective measure of walking stability. Data will be collected using over 50 small reflective markers placed on the participants and the assistive devices, a computerized motion capture system and force plates embedded in the floor. The force plates capture ground reaction forces which will be used to calculate joint moments for interpretation of angular momentum data. The motion capture system will be used to evaluate joint and segment kinematics and temporal-spatial data to characterize the gait pattern in each condition and calculate angular momentum. The second purpose of this research study is to determine the effect of crutch use on participant reported balance confidence and device preference. A validated balance confidence questionnaire and participant satisfaction, comfort and preference will be used to compare between conditions. A numerical pain rating scale (0-10) will be used to assess for any reported pain in all of the conditions. The third purpose of this research is to determine the effect of crutch (HFC and SACs) and boot (with and without) use on walking stability as measured by whole body and segmental angular momentum during gait. Two additional conditions are added to address this purpose (HFC NO BOOT and SAC NO BOOT), resulting in a total of 6 research conditions: 1\) BOOT, 2) HFC + BOOT, 3) SAC + BOOT 4) NONE, 5) HFC NO BOOT, 6) SAC NO BOOT The HFC NO BOOT condition will be evaluated at the end of the HFC + BOOT session, and the SAC NO BOOT condition will be evaluated at the end of the SAC + BOOT session to stay within the fiscal and logistical constraints of the project. Previously described methods will be used. Ultimately, this study could assist physical therapists and other providers in the clinical prescription and application of such devices.

Interventions

DEVICEBOOT

A walking boot is a common type of brace/boot that restricts ankle and foot movement.

DEVICEHFC

The Hands Free Crutch (HFC) by iWalkFree, Inc. is a novel, ambulatory assistive device that prevents foot and ankle loading while also allowing free use of the arms and hands.

DEVICESAC

Standard axillary crutches (SAC) are ambulatory assistive devices, commonly used for lower extremity injuries or surgeries.

DEVICEHFC+BOOT

The Hands Free Crutch (HFC) by iWalkFree, Inc. is a novel, ambulatory assistive device that prevents foot and ankle loading while also allowing free use of the arms and hands. A walking boot is a common type of brace/boot that restricts ankle and foot movement.

DEVICESAC+BOOT

Standard axillary crutches (SAC) are ambulatory assistive devices, commonly used for lower extremity injuries or surgeries. A walking boot is a common type of brace/boot that restricts ankle and foot movement.

Sponsors

iWalkFree, Inc.
CollaboratorINDUSTRY
University of Iowa
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
NONE

Intervention model description

All participants will complete all six testing conditions, including: 1. BOOT (walking boot) 2. HFC + BOOT (Hands Free Crutch with the walking boot) 3. SAC + BOOT (Standard Axillary Crutches with the walking boot) 4. NONE (no device/baseline) 5. HFC NO BOOT (Hands Free Crutch with no walking boot) and 6. SAC NO BOOT (Standard Axillary Crutches with no walking boot). The order of the four primary conditions will be randomized using an online random number generator (1-4) with: 1=NONE, 2=BOOT only, 3=HFC+BOOT, and 4=SAC+BOOT.

Eligibility

Sex/Gender
ALL
Age
18 Years to 45 Years
Healthy volunteers
Yes

Inclusion criteria

* Male or Female * Ages: 18 - 45 * Height between 5'2 and 6'6 * Foot size that corresponds to available walking boots * Healthy individuals without current complaint of lower extremity pain, spine pain, open wounds or active infection * Full active pain free range of motion of the bilateral upper and lower extremities and spine * Able to hop without pain * Able to perform a full squat without pain * Able to walk up and down a flight of stairs at normal walking speed without using the hand rail * Able to stand on one leg for at least 30 seconds * Able to read and write in English and provide written informed consent

Exclusion criteria

* Weight greater than 270 lbs * BMI greater than 35 * Maximum thigh circumference at top of the leg greater than 28 * Prior medical or neuromusculoskeletal disorders that have limited their participation in work or exercise in the last 6 months * Prior lower extremity injury proximal to the ankle requiring surgery or limiting function for greater than 6 weeks * Prior back pain that recurs or has limited activities for greater than 6 weeks * Diagnosed moderate or severe brain injury * Diagnosis of a physical or psychological condition that would preclude testing (e.g. cardiac condition, clotting disorder, pulmonary condition) * Uncorrected visual or hearing impairment(s) * Require use of an assistive device * Pregnancy - Per participant self-report. Due to the expected small number of pregnant individuals, and resulting inability to account for its effect on resulting outcomes, participants will be withdrawn from the study

Design outcomes

Primary

MeasureTime frameDescription
Whole Body Angular Momentum-sagittal Planeone session (up to 2 hours long), out of 4 total sessionsRange of whole-body angular momentum in the sagittal plane during gait using the motion capture system. While angular momentum can be measured in kg\*m\^2/second it is reported as dimensionless in this study as it has been normalized to body weight (kg), height (m), and walking speed (m/s).

Other

MeasureTime frameDescription
Activity-specific Balance Confidence (ABC) ScaleBaselineBalance confidence will be assessed using the ABC Scale on 16 activities, using a 0-100% scale (0% = no confidence and 100% = completely confident).
Numerical Pain Rating Scaleover three sessions (an average of 2 hours for each session)Pain will be assessed using a standard 11-point numerical pain rating scale, in which 0 = no pain and 10 = worst pain imaginable.
Participant Device Comfort ScoreBaselineA modified device comfort scale using an 11-point rating overall score (0=Most Uncomfortable; 10=Most Comfortable).
Participant Device Numerical Scoreover four sessions (an average of 2 hours for each session)A modified device comfort scale using an 11-point rating scale (0=worst assistive device;10=best assistive device).
Participant Device Preferenceone session (up to 2 hours long), out of 4 total sessionsThe participant will rank in order (1-4) their preference of assistive device: NONE, BOOT, HFC and SAC.

Countries

United States

Participant flow

Recruitment details

Participants were recruited by mass email and postings on a university news website between September 2021 and January 2022. The first participant was enrolled on October 5, 2021, and the last participant was enrolled on January 16, 2022.

Pre-assignment details

One participant was enrolled in the study and then failed the post-screening. As a result they were excluded before assignment to the groups.

Participants by arm

ArmCount
NONE, HFC+BOOT, SAC+BOOT, BOOT
The testing order of each of four primary conditions (BOOT, HFC + BOOT, SAC + BOOT, or NONE) will be randomized for each participant.
2
NONE, BOOT, SAC+BOOT, HFC+BOOT
The testing order of each of four primary conditions (BOOT, HFC + BOOT, SAC + BOOT, or NONE) will be randomized for each participant.
2
NONE, SAC+BOOT, BOOT, HFC+BOOT
The testing order of each of four primary conditions (BOOT, HFC + BOOT, SAC + BOOT, or NONE) will be randomized for each participant.
2
NONE, BOOT, HFC+BOOT, SAC+BOOT
The testing order of each of four primary conditions (BOOT, HFC + BOOT, SAC + BOOT, or NONE) will be randomized for each participant.
1
SAC+BOOT, NONE, BOOT, HFC+BOOT
The testing order of each of four primary conditions (BOOT, HFC + BOOT, SAC + BOOT, or NONE) will be randomized for each participant.
3
SAC+BOOT, BOOT, NONE, HFC+BOOT
The testing order of each of four primary conditions (BOOT, HFC + BOOT, SAC + BOOT, or NONE) will be randomized for each participant.
1
BOOT, NONE, SAC+BOOT, HFC+BOOT
The testing order of each of four primary conditions (BOOT, HFC + BOOT, SAC + BOOT, or NONE) will be randomized for each participant.
2
BOOT, NONE, HFC+BOOT, SAC+BOOT
The testing order of each of four primary conditions (BOOT, HFC + BOOT, SAC + BOOT, or NONE) will be randomized for each participant.
2
BOOT, HFC+BOOT, NONE, SAC+BOOT
The testing order of each of four primary conditions (BOOT, HFC + BOOT, SAC + BOOT, or NONE) will be randomized for each participant.
2
HFC+BOOT, BOOT, NONE, SAC+BOOT
The testing order of each of four primary conditions (BOOT, HFC + BOOT, SAC + BOOT, or NONE) will be randomized for each participant.
2
HFC+BOOT, NONE, BOOT, SAC+BOOT
The testing order of each of four primary conditions (BOOT, HFC + BOOT, SAC + BOOT, or NONE) will be randomized for each participant.
1
Total20

Withdrawals & dropouts

PeriodReasonFG000FG001FG002FG003FG004FG005FG006FG007FG008FG009FG010
Overall StudyDidn't feel safe and had pain with hands-free crutch01000000000
Overall StudyOther medical issues unrelated to the study00001000000
Overall StudyUnable to meet the necessary time commitment00100000000

Baseline characteristics

CharacteristicNONE, BOOT, SAC+BOOT, HFC+BOOTNONE, SAC+BOOT, BOOT, HFC+BOOTNONE, BOOT, HFC+BOOT, SAC+BOOTSAC+BOOT, NONE, BOOT, HFC+BOOTSAC+BOOT, BOOT, NONE, HFC+BOOTBOOT, NONE, SAC+BOOT, HFC+BOOTBOOT, NONE, HFC+BOOT, SAC+BOOTBOOT, HFC+BOOT, NONE, SAC+BOOTHFC+BOOT, BOOT, NONE, SAC+BOOTNONE, HFC+BOOT, SAC+BOOT, BOOTHFC+BOOT, NONE, BOOT, SAC+BOOTTotal
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Age, Categorical
Between 18 and 65 years
2 Participants2 Participants1 Participants3 Participants1 Participants2 Participants2 Participants2 Participants2 Participants2 Participants1 Participants20 Participants
Age, Continuous19 years
STANDARD_DEVIATION 1.4
27 years
STANDARD_DEVIATION 12
41 years
STANDARD_DEVIATION 0
27 years
STANDARD_DEVIATION 6.7
27 years
STANDARD_DEVIATION 0
32 years
STANDARD_DEVIATION 14.1
23 years
STANDARD_DEVIATION 3.5
21 years
STANDARD_DEVIATION 3.5
32 years
STANDARD_DEVIATION 1.4
27 years
STANDARD_DEVIATION 7.8
18 years
STANDARD_DEVIATION 0
27 years
STANDARD_DEVIATION 7.8
Ethnicity (NIH/OMB)
Hispanic or Latino
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
2 Participants2 Participants1 Participants3 Participants1 Participants2 Participants1 Participants1 Participants2 Participants2 Participants1 Participants18 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants1 Participants1 Participants0 Participants0 Participants0 Participants2 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Black or African American
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants1 Participants1 Participants0 Participants0 Participants0 Participants2 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants1 Participants0 Participants0 Participants0 Participants0 Participants0 Participants0 Participants1 Participants0 Participants0 Participants2 Participants
Race (NIH/OMB)
White
2 Participants1 Participants1 Participants3 Participants1 Participants2 Participants1 Participants1 Participants1 Participants2 Participants1 Participants16 Participants
Sex: Female, Male
Female
1 Participants1 Participants0 Participants2 Participants1 Participants1 Participants2 Participants1 Participants0 Participants2 Participants1 Participants12 Participants
Sex: Female, Male
Male
1 Participants1 Participants1 Participants1 Participants0 Participants1 Participants0 Participants1 Participants2 Participants0 Participants0 Participants8 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
EG004
affected / at risk
EG005
affected / at risk
EG006
affected / at risk
EG007
affected / at risk
EG008
affected / at risk
EG009
affected / at risk
EG010
affected / at risk
deaths
Total, all-cause mortality
0 / 20 / 20 / 20 / 10 / 30 / 10 / 20 / 20 / 20 / 20 / 1
other
Total, other adverse events
0 / 20 / 20 / 20 / 10 / 30 / 10 / 20 / 20 / 20 / 20 / 1
serious
Total, serious adverse events
0 / 20 / 20 / 20 / 10 / 30 / 10 / 20 / 20 / 20 / 20 / 1

Outcome results

Primary

Whole Body Angular Momentum-sagittal Plane

Range of whole-body angular momentum in the sagittal plane during gait using the motion capture system. While angular momentum can be measured in kg\*m\^2/second it is reported as dimensionless in this study as it has been normalized to body weight (kg), height (m), and walking speed (m/s).

Time frame: one session (up to 2 hours long), out of 4 total sessions

Population: Healthy able-bodied individuals

ArmMeasureValue (MEAN)Dispersion
Arm 1. NONEWhole Body Angular Momentum-sagittal Plane0.051 dimensionlessStandard Deviation 0.009
Arm 2. BOOTWhole Body Angular Momentum-sagittal Plane0.079 dimensionlessStandard Deviation 0.011
Arm 3. HFC+BOOTWhole Body Angular Momentum-sagittal Plane0.095 dimensionlessStandard Deviation 0.01
Arm 4. SAC+BOOTWhole Body Angular Momentum-sagittal Plane0.155 dimensionlessStandard Deviation 0.033
Arm 5. HFCWhole Body Angular Momentum-sagittal Plane0.077 dimensionlessStandard Deviation 0.011
Arm 6. SACWhole Body Angular Momentum-sagittal Plane0.142 dimensionlessStandard Deviation 0.027
Other Pre-specified

Activity-specific Balance Confidence (ABC) Scale

Balance confidence will be assessed using the ABC Scale on 16 activities, using a 0-100% scale (0% = no confidence and 100% = completely confident).

Time frame: Baseline

Population: Healthy able-bodied individuals completed the outcome measure for the arms listed above. They did not complete the outcome measure for HFC+Boot and SAC+Boot.

ArmMeasureValue (MEDIAN)
Arm 1. NONEActivity-specific Balance Confidence (ABC) Scale98.75 score on a scale
Arm 2. BOOTActivity-specific Balance Confidence (ABC) Scale87.50 score on a scale
Arm 3. HFC+BOOTActivity-specific Balance Confidence (ABC) Scale57.50 score on a scale
Arm 4. SAC+BOOTActivity-specific Balance Confidence (ABC) Scale58.82 score on a scale
Other Pre-specified

Numerical Pain Rating Scale

Pain will be assessed using a standard 11-point numerical pain rating scale, in which 0 = no pain and 10 = worst pain imaginable.

Time frame: over three sessions (an average of 2 hours for each session)

Population: Healthy able-bodied individuals completed the outcome measure for the arms listed above. They did not complete the outcome measure for HFC+Boot and SAC+Boot.

ArmMeasureValue (MEAN)Dispersion
Arm 1. NONENumerical Pain Rating Scale0.00 units on a scaleStandard Deviation 0
Arm 2. BOOTNumerical Pain Rating Scale1.12 units on a scaleStandard Deviation 1.76
Arm 3. HFC+BOOTNumerical Pain Rating Scale2.59 units on a scaleStandard Deviation 1.73
Arm 4. SAC+BOOTNumerical Pain Rating Scale2.47 units on a scaleStandard Deviation 1.91
Other Pre-specified

Participant Device Comfort Score

A modified device comfort scale using an 11-point rating overall score (0=Most Uncomfortable; 10=Most Comfortable).

Time frame: Baseline

Population: Healthy able-bodied individuals completed the outcome measure for the arms listed above. They did not complete the outcome measure for HFC+Boot and SAC+Boot.

ArmMeasureValue (MEAN)Dispersion
Arm 1. NONEParticipant Device Comfort Score9.76 score on a scaleStandard Deviation 0.44
Arm 2. BOOTParticipant Device Comfort Score7.82 score on a scaleStandard Deviation 1.13
Arm 3. HFC+BOOTParticipant Device Comfort Score5.00 score on a scaleStandard Deviation 2.62
Arm 4. SAC+BOOTParticipant Device Comfort Score5.12 score on a scaleStandard Deviation 2.09
Other Pre-specified

Participant Device Numerical Score

A modified device comfort scale using an 11-point rating scale (0=worst assistive device;10=best assistive device).

Time frame: over four sessions (an average of 2 hours for each session)

Population: Healthy able-bodied individuals completed the outcome measure for the arms listed above. They did not complete the outcome measure for HFC+Boot and SAC+Boot.

ArmMeasureValue (MEAN)Dispersion
Arm 1. NONEParticipant Device Numerical Score9.06 score on a scaleStandard Deviation 1.6
Arm 2. BOOTParticipant Device Numerical Score8.00 score on a scaleStandard Deviation 1.37
Arm 3. HFC+BOOTParticipant Device Numerical Score6.35 score on a scaleStandard Deviation 2.83
Arm 4. SAC+BOOTParticipant Device Numerical Score5.94 score on a scaleStandard Deviation 1.95
Other Pre-specified

Participant Device Preference

The participant will rank in order (1-4) their preference of assistive device: NONE, BOOT, HFC and SAC.

Time frame: one session (up to 2 hours long), out of 4 total sessions

Population: Healthy able-bodied individuals completed the outcome measure for the arms listed above. They did not complete the outcome measure for HFC+Boot and SAC+Boot.

ArmMeasureGroupValue (NUMBER)
Arm 1. NONEParticipant Device PreferencePreference 42 participants
Arm 1. NONEParticipant Device PreferencePreference 115 participants
Arm 1. NONEParticipant Device PreferencePreference 30 participants
Arm 1. NONEParticipant Device PreferencePreference 20 participants
Arm 2. BOOTParticipant Device PreferencePreference 12 participants
Arm 2. BOOTParticipant Device PreferencePreference 32 participants
Arm 2. BOOTParticipant Device PreferencePreference 213 participants
Arm 2. BOOTParticipant Device PreferencePreference 40 participants
Arm 3. HFC+BOOTParticipant Device PreferencePreference 44 participants
Arm 3. HFC+BOOTParticipant Device PreferencePreference 10 participants
Arm 3. HFC+BOOTParticipant Device PreferencePreference 310 participants
Arm 3. HFC+BOOTParticipant Device PreferencePreference 23 participants
Arm 4. SAC+BOOTParticipant Device PreferencePreference 411 participants
Arm 4. SAC+BOOTParticipant Device PreferencePreference 10 participants
Arm 4. SAC+BOOTParticipant Device PreferencePreference 35 participants
Arm 4. SAC+BOOTParticipant Device PreferencePreference 21 participants

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026