Socket Geometry and Clinical Outcomes of Manual vs Digital Sockets for Lower-limb Amputees

NCT06504303 | Completed

• 1 other identifier: 20-013-WP
• Study Type: interventional
• Target: 10
• Locations: 1 country
• Sites: 1

Brief Summary

The most important aspect of a lower-limb prosthesis is the socket as the interface between the human and the mechanical prosthetic system. Proper fit of the socket to the residual limb is a critical factor in determining comfort, suspension, energy expenditure and ultimately the functional efficiency of the remaining prosthesis. Patients may not wear their prosthesis if they find the socket uncomfortable. Traditional manufacturing of prosthetic sockets is a high-skill process involving several stages. Capturing the shape of the residual limb and modifying the mould is performed with a manual, hands-on approach. This leads to inconsistencies between clinicians, and increases the likelihood of human error. There is opportunity to improve this process with advanced computer-aided design (CAD) and manufacturing (CAM). 3D printing can be leveraged for its ability to effortlessly manufacture one-off, complex and organic shapes, such as prosthetic sockets. However, the digital method removes the tactile feedback that the clinician generally benefits from when manually designing the socket, thus leading to some uncertainty in how they are modifying the socket. Moreover, the difference in the learning curve may cause inconsistencies in modifications made by different clinicians. While clinicians may be hesitant in their knowledge-transfer from a manual to digital method, sockets designed using CAD still produce successful outcomes. To facilitate wider-spread adoption of 3D printing as a standard tool in the clinic, more research is needed to better understand how the digital design process affects the geometry of the socket, and how this affects clinical outcomes for amputees. The investigators hypothesize that (1) digitally-designed sockets and manually-designed sockets will have geometric differences, (2) the digitally-designed socket will result in better clinical outcomes compared to manually-designed sockets, and (3) improved clinical outcomes will correlate to geometric differences centred on particular regions of the socket. However, a feasibility study is needed to inform an effective protocol. This feasibility study aims to explore socket geometries and prosthetic outcomes compared between manually-designed and digitally-designed devices for lower-limb amputees. Findings will help in improving the current 3D printing techniques and exploring outcomes for the users.

Conditions

Amputation

Keywords

Transtibial amputation; Prosthesis; 3D printing; Additive manufacturing; Computer-aided design; Socket Comfort Score

Outcome Measures

Primary Outcomes (3)

• Patient recruitment rates

  The number of eligible vs. recruited patients will be tracked throughout the study period.

  Through study completion, an average of 1 year

• Adherence to protocol

  Adherence to protocol steps (i.e., casting, CAD, 3D printing, or functional testing protocols) will be tracked throughout the study period and a standardized checklist of procedures will be kept to measure the rate at which procedures are implemented as intended for fidelity assessment.

  Through study completion, an average of 1 year

• Patient retention rates

  Patient drop-out rate will be tracked throughout the study period.

  Through study completion, an average of 1 year

Secondary Outcomes (4)

• Socket geometric differences

  Through study completion, an average of 1 year

• Socket comfort score change

  Through study completion, an average of 1 year

• Two-minute walk test

  Performed one day prior to discharge from West Park.

• L-test

  Through study completion, an average of 1 year

Other Outcomes (2)

• Demographics

  Through study completion, an average of 1 year

• Physiological Cost Index

  Through study completion, an average of 1 year

Study Arms (1)

3D-printed socket

EXPERIMENTAL

The 3D scan of the participant's residual limb will be digitally-modified and fabricated using 3D printing.

Device: 3D-printed socket

Interventions

3D-printed socket DEVICE

During the shape-capturing in-patient appointment, participants will be measured for the prosthetic device through (1) manual casting using Plaster of Paris bandages and (2) scanning using a 3D scanner. The clinician will manually modify the positive plaster cast and digitally modify the scanned impression using OMEGA software. The manually-modified positive cast will be digitized by scanning the cast, then 3D-printed. The digitally-modified socket file will also be 3D printed. The research investigator will make a de-identified mark on each socket to differentiate between the two sockets after 3D printing, and will record the order in which the sockets are fit to the patient.

3D-printed socket

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• In-patient adults (18 years and older)
• Unilateral transtibial amputation
• Eligible to receive a preparatory prosthetic device
• Able to communicate in English orally and in writing
• Able to tolerate participating in an additional 30- minute 3D scanning session

You may not qualify if:

• Presentation of significant cognitive impairment
• History of epilepsy
• On dialysis at any point of the duration of the study

Sponsors & Collaborators

• West Park Healthcare Centre: lead

Study Sites (1)

West Park Healthcare Centre

Toronto, Ontario, M6M 2J5, Canada

Location

Study Officials

• Winfried Heim, MSc, C.P.(c)

  West Park Healthcare Centre

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: OTHER
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Participants will be measured for a prosthetic device through (1) manual casting using Plaster of Paris bandages and (2) scanning using a 3D scanner. Subjects will be given a patient experience survey to score their experience with each shape capturing process. Two sockets, one made from each of the two shape-capturing methods, will be 3D printed. Both sockets will be fitted to the subject. The immediate socket fit will be recorded by the number of filler sock plys needed to be added in the socket. Subjects will continue therapy using the socket that is more comfortable and fits better, based on both the subject's judgment and the judgment of their clinician. If the subject finds both sockets as equally comfortable, he/she will get to choose the preferred socket to continue with for therapy.

Study Record Dates

• First Submitted: July 28, 2021
• First Posted: July 16, 2024
• Study Start: November 10, 2021
• Primary Completion: November 30, 2023
• Study Completion: November 30, 2023
• Last Updated: July 16, 2024

Record last verified: 2024-07

Data Sharing

• IPD Sharing: Will not share

Locations

CA (1)