ClinicalTrials.gg
CompletedNCT05038566Updated Jan 17, 2025Results posted

Dexterous Partial Hand Prosthesis Outcomes

An interventional study of Pointdexter in Amputation, Amputation; Traumatic, Hand and Limb; Absence, Congenital, Upper, sponsored by Liberating Technologies, Inc.. Completed at 2 sites in United States. Per ClinicalTrials.gov, last updated 2025-01-17.

Sponsored by Liberating Technologies, Inc. · Not applicable, Interventional, and Device feasibility

Phase
Not applicable
Study type
Interventional
Enrollment
4
Allocation
Randomized
Sex
All
01

Study summary

Liberating Technologies, Inc. (LTI) has developed a dexterous prosthetic fingertip that will be fit onto an i-Digits™ partial hand prosthesis and allow for an additional fine grasp. The device will interface with research participants' existing prostheses and use the same control strategy that is used for their everyday use. Each participant's prosthesis will be restored to their original configuration by the end of their testing period.

Read the detailed description

Liberating Technologies, Inc. (LTI) has developed a dexterous prosthetic fingertip that will be fit onto an i-Digits™ partial hand prosthesis and allow for an additional fine grasp. The device will interface with research participant's existing prostheses and use the same control strategy that is used for their everyday use. Each participant's prosthesis will be restored to their original configuration by the end of their testing period.

The study will focus on design feasibility testing and will compare performance of hand functional outcome tests on an i-Digits™ prosthetic partial hand with and without the investigational Pointdexter modification. Our primary hypothesis is that subjects using the investigational device will show better performance on objective functional outcomes measures than those using a standard i-Digits™ partial hand prosthesis, particularly in the manipulation of small objects.

The investigators will explore multiple outcomes measures as options, but our primary endpoint will be performance on the Small Common Objects subtask of the Jebsen-Taylor Hand Function Test, which assesses a broad range of unimanual hand functions required for ADLs. The primary quantitative measure of the Jebsen-Taylor task will be completion time of each subtask. Qualitative evaluation will be conducted by an occupational therapist via observation, and by the user through a self-assessment questionnaire, such as the Patient Specific Functional Scale (PSFS). The investigators will be performing repeated measures on each individual subject to reduce the variance as well as having each subject act as their own control. New and existing i-Digits™ partial hand prosthesis users will be recruited for the study and consented with an approved protocol. Research participants will schedule a time to conduct the testing and be informed of study details.

The investigational device being tested is a novel prosthetic finger with a built-in split gripper. The device is an index finger which can drop in place of existing digits on an i-Digits™ partial hand prosthesis. The investigational device is controlled with the same signals as the conventional digits.

This study will pilot test the dexterous fingertip prosthesis with a small number of subjects (up to 12). Research participants will be consented and will test the device at home and/or in-lab. Subjects will be introduced to the partial hand prosthesis configuration and be instructed on how to operate it to complete their testing session.

The in-lab testing will be conducted in a single site visit at Össur Academy in Dublin, Ohio or LTI in Holliston, MA. Subjects may be asked to come back for an additional site visit if data collection is incomplete. For this study, the index finger of each participant's existing everyday prosthesis will be temporarily disconnected and replaced with the investigational device. The prosthesis will be restored to its original configuration when the test session has been completed. At the start of the study session, subjects will prepare for testing in their first configuration (investigational or comparator). If investigational, subjects will doff their prosthesis and investigators will replace the usual i-Digits™ index finger with the investigational device. If comparator, subjects will don their usual unmodified prosthesis. Subjects will be trained on how to operate the investigational device and be allowed a minimum of 30 minutes to practice using it until they are comfortable with proceeding. The subjects will be guided to conduct functional outcome tests that involve picking up and manipulating everyday objects (beans, coins, pegs, spoon, cloth, etc.), such as the tasks outlined in the Jebsen-Taylor and Peg Board functional tests. Each sub-task in the functional test will be scored by occupational therapist standards. After a round of functional testing is done, subjects will fill out the PSFS survey and subjective questionnaire. Subjects will then doff the prosthesis and don the next device configuration. The PSFS survey as well as user and clinician feedback are both exploratory outcome measures as the design is still in very early prototype stages. The intent of this feedback is to help iterate the design to assist in further development of the final product. Subjects will repeat the functional tests and surveys with each device configuration. After the final condition, the subject will have completed the study and their prosthesis will be restored to its usual configuration. The study session should span 3-5 hours.

A subset of subjects will take home the investigational device for up to 4 weeks to provide feedback of the device when used in everyday tasks. Investigators will restore the user's prosthesis at the end of the testing period and surveys will be conducted to capture feedback. Two site visits may be required: one to initialize the study and configure the prosthesis, and two to restore the prosthesis at the study end. This feedback is also an exploratory outcome measure due to the design being in very early prototype stages.

Both new and existing i-Digits™ partial hand prosthesis users will be invited to participate in the study. Research participants will schedule a time to conduct the testing and be informed of study details. Participants will be given as much time as needed to review and question the informed consent form before signing.

Two different technologies will be assessed:

  • Investigational Device: i-Digits™ partial hand prosthesis with dexterous fingertip modification
  • Comparator Baseline: unmodified i-Digits™ partial hand prosthesis

Persons with partial hand limb absence who are new or current i-Digits™ prosthesis users will be recruited for this study through the LTI and Össur clinician network. Prosthetists may be contacted with the need for research subjects and, if interested, will be given flyers to hand out to their patients. If subjects are interested in participating, they can call the number on the flyer to speak with investigators. In addition, previous research participants who have given permission to be contacted for future studies may be contacted directly to assess interest in participating in this study. Enrollment will be open to people of all ages, genders, races, and ethnicities. Participants must be new or current users of i-Digits™ partial hand prostheses. The user must have an absent index finger at minimum. Patients who have 4-5 digit and/or thumb involvement will be preferred.

Based on subject population and availability, a convenience sample of up to 12 subjects will be recruited for this pilot study.

02

Conditions studied

  • Amputation
  • Amputation; Traumatic, Hand
  • Limb; Absence, Congenital, Upper
  • Prosthesis User
  • Upper Limb Amputation at the Hand

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Keywords

  • amputee
  • upper limb amputee
  • partial hand prosthesis user
  • prosthesis
  • i-Digits
  • upper limb loss
  • prosthetist
  • gripper
  • dexterous fingertip
  • index finger prosthesis
03

In context

Amputation, Traumatic

112 studies on the registry are indexed under Amputation, Traumatic; 24 are open to participants now.

This study's enrollment of 4 is below the median of 15 across 75 interventional studies indexed under Amputation, Traumatic.

Browse Amputation, Traumatic studies →

Lead sponsor

Liberating Technologies, Inc. is the lead sponsor of 15 studies on the registry; 4 are open to participants now.

Of its 7 completed or terminated interventional studies of FDA-regulated products, 5 (71%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
Child (0–17), Adult (18–64), Older adult (65+)
Sexes eligible
All
Accepts healthy volunteers
Yes

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Must have an upper limb partial hand absence.
  • Must be new or current i-Digits prosthesis users.
  • Must have an absent index finger at minimum.
  • Must be able to understand spoken and written English in order to be properly consented and provide feedback to the study personnel.
  • Must be willing and able to complete outlined tasks and provide feedback on the intervention.

Exclusion criteria

Exclusion Criteria:

  • The risks to pregnant women and fetuses are unknown and therefore pregnant women should not participate in the study.
05

Study design

Phase
Not applicable
Primary purpose
Device feasibility
Allocation
Randomized
Intervention model
Crossover assignment
Masking
None (open label)
Enrollment
4 participants (actual)

Study arms

  • No intervention
    Comparator Baseline

    The subject's usual partial hand prosthesis

  • Experimental
    Pointdexter

    The subject wears a modified version of their usual partial hand prosthesis. The modification replaces the usual index finger of the partial hand prosthesis with the investigational Pointdexter device.

    Device: Pointdexter

Interventions

  • DevicePointdexter

    i-Digits partial hand prosthesis modified with the investigational pointdexter finger in place of the usual index finger.

    Also known as: Dexterous Partial Hand Prosthesis, Gripper

06

What researchers measure

Primary outcomes

  1. Jebsen-Taylor Small Common Objects Functional Test

    During the in-lab portion of the study, subjects will be asked to complete the 'small common objects' subtask of the Jebsen-Taylor Hand Function Test, which assesses a broad range of unimanual hand functions required for ADLs. The primary quantitative measure of the Jebsen-Taylor task will be completion time of each subtask. The maximum time allotted for each task was 120 seconds, at which point the subject was told to stop the task and the time was reported as the maximum 120 seconds. This test will be used to evaluate the feasibility of the device design as compared with a baseline condition. This was the only primary outcome measure collected for this study. There were no secondary outcome measures, only exploratory measures as this is a very early prototype design that is still in the design iteration stages.

    Time frame: 4 hours at a single site visit

07

Results

Posted Jan 17, 2025

Participant flow

Participant flow — Overall Study
MilestoneComparator Baseline, Then PointdexterPointdexter, Then Comparator Baseline
Started22
Completed21
Not completed01
Withdrew: Technical difficulties with the device01

Outcome measures

PrimaryJebsen-Taylor Small Common Objects Functional Test

During the in-lab portion of the study, subjects will be asked to complete the 'small common objects' subtask of the Jebsen-Taylor Hand Function Test, which assesses a broad range of unimanual hand functions required for ADLs. The primary quantitative measure of the Jebsen-Taylor task will be completion time of each subtask. The maximum time allotted for each task was 120 seconds, at which point the subject was told to stop the task and the time was reported as the maximum 120 seconds. This test will be used to evaluate the feasibility of the device design as compared with a baseline condition. This was the only primary outcome measure collected for this study. There were no secondary outcome measures, only exploratory measures as this is a very early prototype design that is still in the design iteration stages.

Time frame:
4 hours at a single site visit
Reported as:
Mean · Seconds
Jebsen-Taylor Small Common Objects Functional Test
SecondsComparator BaselinePointdexter
Turning a Card Over34.8 ± 20.526.1 ± 4.5
Small Common Objects97.2 ± 32.262.1 ± 2.2
Stacking Checkers37.5 ± 43.128 ± 21.8
Manipulating Cloth5.4 ± 1.55.8 ± 1.7
Holding a Screw24.1 ± 1.865.7 ± 34.7
9-Hole Out11.4 ± 8.123.3 ± 19
9-Hole In120 ± 063.8 ± 57.3
Removing Pen Cap5.8 ± 2.37.1 ± 4.2
Tying Shoe Laces50.5 ± 4934.6 ± 1.1
Zipping a Zipper32.6 ± 10.2120 ± 0
Threading a Needle120 ± 032.4 ± 8.1
Simulated Feeding30.1 ± 2266.3 ± 76
Large Light Objects11.7 ± 4.214.3 ± 3.7
Large Heavy Objects17.8 ± 4.616.7 ± 5

Adverse events

Collected over For the in-lab portion of the study, adverse events were monitored/assessed throughout the entire in-lab session, which was conducted over the course of 1 day. For the take-home early stage feasibility portion of the study, adverse events were monitored/assessed throughout the amount of time that subjects had the investigative device at home, which was up to 4 weeks.. Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Comparator Baseline0/4 (0%)0/4 (0%)0/4 (0%)
Pointdexter0/4 (0%)0/4 (0%)0/4 (0%)

Baseline characteristics

Persons with partial hand amputation or partial hand difference with at least 4-5 digit involvement including the index finger.

Age, Categorical
Age, Categorical(Participants)Comparator Baseline, Then Pointdexter (~4 Hours of In-lab Testing)Pointdexter, Then Comparator Baseline (~4 Hours of In-lab Testing)Total
<=18 years000
Between 18 and 65 years224
>=65 years000
Sex: Female, Male
Sex: Female, Male(Participants)Comparator Baseline, Then Pointdexter (~4 Hours of In-lab Testing)Pointdexter, Then Comparator Baseline (~4 Hours of In-lab Testing)Total
Female000
Male224
Ethnicity (NIH/OMB)
Ethnicity (NIH/OMB)(Participants)Comparator Baseline, Then Pointdexter (~4 Hours of In-lab Testing)Pointdexter, Then Comparator Baseline (~4 Hours of In-lab Testing)Total
Hispanic or Latino000
Not Hispanic or Latino224
Unknown or Not Reported000
Race (NIH/OMB)
Race (NIH/OMB)(Participants)Comparator Baseline, Then Pointdexter (~4 Hours of In-lab Testing)Pointdexter, Then Comparator Baseline (~4 Hours of In-lab Testing)Total
American Indian or Alaska Native000
Asian000
Native Hawaiian or Other Pacific Islander000
Black or African American000
White224
More than one race000
Unknown or Not Reported000
Region of Enrollment
Region of Enrollment(Participants)Comparator Baseline, Then Pointdexter (~4 Hours of In-lab Testing)Pointdexter, Then Comparator Baseline (~4 Hours of In-lab Testing)Total
United States224
08

Study locations

2 sites
  • Liberating Technologies, Inc.
    Holliston, Massachusetts 01746, United States
  • Össur Academy - Touch Solutions
    Dublin, Ohio 43017, United States
09

References and documents

Study documents

PDFs hosted by the registry, ClinicalTrials.gov.

Individual participant data

Plan to share: No

10

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Jan 17, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
11

Registry details

Key details

Study ID
NCT05038566
Lead sponsor
Liberating Technologies, Inc.
Collaborators
Össur Iceland ehf
Responsible party
Todd Farrell (Director of Research, Liberating Technologies, Inc.) — Principal investigator
First posted
Sep 9, 2021
Start date
Jul 15, 2021
Primary completion
Apr 28, 2022
Completion
Apr 28, 2022
Results posted
Jan 17, 2025
Last update
Jan 17, 2025

Study contacts

Todd Farrell, PhD
principal investigator · Liberating Technologies, Inc.

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
Yes
View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in Jan 2025. You cannot join it, but the record below documents what was studied.

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