Limb Health and Socket Pressure in Response to Powered Ankle Protheses (OPORP)

Limb Health and Socket Pressure in Response to Powered Ankle Prostheses

this project seeks to understand and quantify the effects of powered transtibial prostheses on socket loading and direct measures of residual limb health so as to inform the optimization of prosthesis fit.

Study Overview

• Status: Completed
• Conditions: Amputation; Prosthesis User; Mobility Limitation; Pressure Ulcer, Ankle; Prosthesis Durability; Skin Wound; Amputation; Traumatic, Foot; Limb Deficiencies
• Intervention / Treatment: Device: PROPRIO FOOT® by Ossur & Empower ankle by Ottobock

Detailed Description

Some estimates suggest that by 2050, as many as 3.6 million people in the United States will be living with limb loss, and at least 60% of them will have had at least a foot removed For military personnel, combat-related amputations remain one of the most common major disabling war-related injuries from modern armed conflict. Technological advancements in active prosthetic devices for individuals with transtibial amputation offer the potential for superior function in key areas that could lead to higher rates of RTD and improved quality of life. Currently intended primarily for individuals with a K-level of 3 or 4, active transtibial prostheses that provide controlled plantar/dorsiflexion in either swing (microprocessor-controlled prostheses) or late stance (prostheses with powered propulsion) are likely to become the gold standard in the future as technology continues to improve Indeed, users of these types of prostheses have higher mobility than those using any of the other four categories of prosthetic ankle-foot mechanisms for unlimited community ambulators. Note that a major insurer has recently declared microprocessor-controlled ankle-foot prostheses medically necessary for members whose functional level is 3 or above.The PROPRIO FOOT® by Ossur, is a microprocessor-controlled prosthesis that regulates the angle of ankle dorsiflexion during the swing phase. This added ankle control of these devices reduces the risk of falls by increasing toe clearance supports more natural standing posture on slopes and improves stair and slope ascent/descent capability by adapting to the change in terrain. On stairs, the PROPRIO FOOT® has been shown to improve affected leg knee kinematics (increased knee flexion) and kinetics (increased knee moment) instance. These improvements also contributed to higher interlimb symmetry reduced energetic cost of slope ascent and higher Amputee Mobility Predictor with a Prosthesis (AMPPRO) scores . Although the ankle of the PROPRIO FOOT® can be controlled in swing, the device does not have adequate power to provide an active propulsion instance. The Empower ankle by Ottobock is a powered prosthesis that provides active propulsion in late stance to mimic the positive work performed by the ankle plantar flexors in push-off. The Empower has been shown to improve affected leg kinematics (increased ankle range of motion and reduced knee flexion) on smooth flat ground ramp ascent and gravel]. In terms of kinetics, the Empower likewise results in increased ankle power on level ground stairs and ramps . Active prostheses like the PROPRIO FOOT® and Empower ankle offer great potential to more completely restore the locomotor capabilities of individuals with transtibial amputation, perhaps enhancing RTD for military personnel. As with all prosthetic components, though, these active devices are of little use if they induce pain and/or injury at the residual limb to the degree that the user will simply not wear them. The investigators will examine how optimal fit of lower limb prostheses can impact individuals comfort and/or reduce irritation.

• Study Type: Interventional
• Enrollment (Actual): 6
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Indiana
    • Indianapolis, Indiana, United States, 46228
      • Indiana University Health Methodist Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Ages 18 and above
• Weight ≤ 280 lb
• Ambulate at a K3 level or higher-level determined from patient EHR
• At least 3 months post-amputation per physician discretion
• Residual limb length greater than 4.5 inches
• Use of a passive prosthesis
• Unilateral transtibial amputees
• Must be able to ambulate without any assistive devices
• Subjects must be able to follow directions and give informed consent on their own

Exclusion Criteria:

• Conditions and/or co-morbidities that would prevent wearing a prosthetic socket, affect gait, or influence function of the contralateral limb
• Other amputees
• Cognitive deficits or mental health problems that would limit ability to consent and participate fully in the study protocol
• Women who are pregnant or who plan to become pregnant in the near future
• Individuals diagnosed with renal failure
• Participants unwilling to wear a cloth face covering for the duration of each visit

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Proprio Foot; each participant was randomized to use Proprio or empower based on randomization followed by switching the other empower or proprio	Device: PROPRIO FOOT® by Ossur & Empower ankle by Ottobock; PROPRIO FOOT is a microprocessor controlled foot that offer great potential to more completely restore the locomotor capabilities of individuals with transtibial amputation, Empower: Empower powered ankle offer great potential to more completely restore the locomotor capabilities of individuals with transtibial amputation.
Experimental: Empower foot; ach participant was randomized to use Proprio or empower based on randomization followed by switching the other empower or proprio	Device: PROPRIO FOOT® by Ossur & Empower ankle by Ottobock; PROPRIO FOOT is a microprocessor controlled foot that offer great potential to more completely restore the locomotor capabilities of individuals with transtibial amputation, Empower: Empower powered ankle offer great potential to more completely restore the locomotor capabilities of individuals with transtibial amputation.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Powered Transtibial Prosthesis on Socket Pressure	effects of a powered transtibial prosthesis on the socket pressure for level-ground walking to a microprocessor-controlled prosthesis and a passive prosthesis	4 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Skin Perfusion	Changes measured with laser speckle imaging. The perfusion data is expressed as perfusion units (PU) which is a dimensionless ratio calculated by dividing the standard deviation of the intensity in a given area by the mean intensity within that area, essentially representing the degree of variation in the speckle pattern. Higher number indicates greater perfusion which is better outcome.	4 weeks
Transepidermal Water Loss (TEWL)	Water loss change is measured via the TEWL device- the lower score mean a better outcome for TEWL.	4 weeks

Collaborators and Investigators

• Sponsor: Indiana University
• Collaborators: United States Department of Defense; University of Notre Dame
• Investigators: Principal Investigator: Sashwati Roy, PhD, Indiana University

Study record dates

Study Major Dates

• Study Start (Actual): November 15, 2021
• Primary Completion (Actual): July 19, 2023
• Study Completion (Actual): July 19, 2023

Study Registration Dates

• First Submitted: August 13, 2021
• First Submitted That Met QC Criteria: November 4, 2021
• First Posted (Actual): November 9, 2021

Study Record Updates

• Last Update Posted (Estimated): November 25, 2025
• Last Update Submitted That Met QC Criteria: November 19, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Postoperative Complications; Pathologic Processes; Skin Diseases; Skin Ulcer; Pathological Conditions, Signs and Symptoms; Skin and Connective Tissue Diseases; Signs and Symptoms; Mobility Limitation; Pressure Ulcer; Prosthesis Failure
• Other Study ID Numbers: 12350

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The investigators will share deidentified patient data consisting of the patient PEQ and comfort scores and transpepidermal water loss data upon request.
• IPD Sharing Time Frame: 6 months after completion
• IPD Sharing Access Criteria: Email study contact
• IPD Sharing Supporting Information Type: SAP; ICF

Drug and device information, study documents

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