Northwestern University Feinberg School of Medicine

Northwestern University Prosthetics-Orthotics Center

No Longer Smooth: Introducing Striations into Prosthetic Socket Construction to Improve Suspension, Rotation, Fit and Comfort

Principal Investigator: Stefania Fatone, PhD, BPO(Hons)

Co-Investigators: Steven A. Gard, PhD; Rebecca Stine, MS; Marc Applebaum, MD (Jesse Brown VA Medical Center)

Collaborators: Brad Poziembo, LP, Prosthetic Design Inc. (PDI); Tracy Slemker, CPO 

Project Director: Julia Quinlan, PhD 

Other Study Staff: Vasanth Subramanian, MS; Lilly Tran, MS; Jessica Yohay, BS; J. Chad Duncan, PhD, CPO  

Status: In Progress 

Acknowledgment: 
The U.S. Army Medical Research Acquisition Activity, 820 Chandler Street, Fort Detrick MD 21702-5014 is the awarding and administering acquisition office. This work is supported by the Office of the Assistant Secretary for Health Affairs, through the Neuromusculoskeletal Injuries Research Award under Award No. W81XWH-16-1-0485. Opinions, interpretations, conclusions and recommendations are those of the author and are not necessarily endorsed by the U.S. Department of Defense. 

Introduction

Conventional prosthetic sockets are typically smooth on the inner surface, which may cause the prosthesis to slide or rotate on the residual limb. The prosthetic sockets to be investigated for this study are textured on the inside and may prevent relative movement between the prosthesis and the residual limb. Hence, this study will investigate a new design in prosthetic socket that may be more comfortable and enable greater control by the prosthesis user.

Objective/Hypothesis 

The objective of this pre-clinical research project is to investigate the effect of different types of inner surface texturing on the suspension, rotation, fit, and comfort of prosthetic sockets. We hypothesize that horizontal striations will improve suspension while vertical striations will help control transverse plane rotation. It is possible that in combination, both suspension and rotation may be improved. However, striations may vary in either direction in depth and pattern and it remains unknown what combinations might maximize suspension and rotation benefits without compromising fit, comfort and durability.

Study Design

This project will utilize an existing SQUIRT-Shape Rapid Prototyping System to construct sockets inexpensively with varying types of texturing (See figure).

Sockets with varying types of texturing

Specific aims will
(1) test the force needed to displace the socket longitudinally and rotationally;
(2) test the coefficient of friction, tensile and static strength of sockets with different texturing patterns; and
(3) test the comfort and fit of textured sockets on Veterans with transtibial amputation.

The first two aims use various bench-top tests to develop an understanding of the mechanical properties and potential benefits of textured sockets as compared to conventional smooth thermoformed sockets. The last aim will assess the socket fit and comfort of textured sockets that perform well in aims 1 and 2 on five Veterans with transtibial amputation in a randomized, double-blind, cross-over study. 

Publications

Quinlan J, Yohay J, Subramanian V, Poziembo B, Fatone S (2020) Using mechanical testing to assess the effect of lower-limb prosthetic socket texturing on longitudinal suspension. PLoS ONE 15(8): e0237841. https://doi.org/10.1371/journal.pone.0237841 (Research data associated with this publication is archived at https://digitalhub.northwestern.edu/collections/19673087-b6a5-4108-b285-9614aa8b6b95 )

Quinlan J, Subramanian V, Yohay J, Poziembo B, Fatone S (2020) Using mechanical testing to assess texturing of prosthetic sockets to improve suspension in the transverse plane and reduce rotation. PLoS ONE 15(6): e0233148. https://doi.org/10.1371/journal.pone.0233148 (Research data associated with this publication is archived at https://digitalhub.northwestern.edu/collections/d50c6f56-2600-4e67-ba4f-ee681eeae64c )

Quinlan J, Baer G, Subramanian V, Yohay J, Poziembo B, Richardson R, Fatone S. (2019) Tensile and Coefficient of Friction Testing of Textured Prosthetic Socket Specimens Provide Insights on Strength and Friction. Journal of Prosthetics and Orthotics, 31(S2):32.

Quinlan J, Tran L, Yohay J, Poziembo B, Fatone S (2018) Mechanical Testing of Textured Prosthetic Sockets Provides Insight on Improving Suspension. Journal of Prosthetics and Orthotics, 30(S2):39.

Presentations

2019

Fatone S (2019) What We Have Learnt from Mechanical Testing of Textured 3D Printed Prosthetic Sockets Invited Presentation, AOPQ-AQIPA 2019 Congress, October 18-20, St-Hyacinthe, Quebec, Canada.

Quinlan J, Subramanian V, Yohay J, Poziembo B, Fatone S (2019) Mechanical Testing of Textured Prosthetic Sockets. International Society for Prosthetics and Orthotics World Congress, October 5-8, Kobe, Hyogo, Japan.

Quinlan J, Subramanian V, Yohay J, Poziembo B, Fatone S (2019) Mechanical Performance of Textured 3D Printed Prosthetic Sockets. American Orthotics and Prosthetics Association National Assembly, September 25-28, 2019, San Diego, California.

Quinlan J, Subramanian V, Yohay J, Poziembo B, Fatone S (2019) What We Have Learnt from Mechanical Testing of Textured 3D Printed Prosthetic Sockets. Midwest Chapter of the American Academy of Orthotists and Prosthetists, September 13-14, Lake Geneva, Wisconsin.

Quinlan J, Subramanian V, Yohay J, Baer G, Poziembo B, Fatone S (2019) Tensile and Coefficient of Friction Testing of Textured Socket Specimens. 2019 Current Research and Future Careers 7th annual symposium of the Northwestern Postdoctoral Association, Northwestern University, August 22, Chicago, IL.

Quinlan J, Subramanian V, Yohay J, Baer G, Poziembo B, Fatone S. (2019) Tensile and Coefficient of Friction Testing of Textured Prosthetic Socket Specimens. 15th Annual Lewis Landsberg Research Day, April 4, Chicago, IL.

Quinlan J, Baer G, Subramanian V, Yohay J, Poziembo B, Richardson R, Fatone S. (2019) Tensile and Coefficient of Friction Testing of Textured Prosthetic Socket Specimens Provide Insights on Strength and Friction. American Academy of Orthotists & Prosthetists Annual Meeting & Scientific Symposium, March 6-9, 2019, Orlando, FL.

Quinlan, J (2019) BME Research Project: No Longer Smooth. 48th Annual Career Day for Girls, The Society of Women Engineers, Northwestern University Chapter, McCormick School of Engineering, February 23, Evanston, IL. 

2018 

Quinlan J, Baer G, Subramanian V, Yohay J, Poziembo B, Richardson R, Fatone S (2018) Tensile and Coefficient of Friction Testing of Textured Prosthetic Socket Specimens. Midwest Chapter of the American Academy of Orthotists and Prosthetists, September 13-15, Lake Geneva, WI. 

Quinlan J, Tran L, Yohay J, Poziembo B, Fatone S (2018) The effect of prosthetic socket texturing on socket suspension using mechanical loading 14th Annual Lewis Landsberg Research Day, Northwestern University, April 5, Chicago, IL.

Quinlan J, Tran L, Yohay J, Poziembo B, Fatone S (2018) “Mechanical Testing of Textured Prosthetic Sockets Provides Insight on Improving Suspension.” American Academy of Orthotists & Prosthetists Annual Meeting & Scientific Symposium, February 14-17, 2018, New Orleans, LA.

2017 

Quinlan J, Tran L, Yohay J, Poziembo B, Fatone S (2017) The effect of prosthetic socket texturing on socket suspension using mechanical loading. Scheck & Siress Education Fest, April 27-28, Lombard, IL. 

Quinlan J, Tran L, Yohay J, Poziembo B, Fatone S (2017) The effect of prosthetic socket texturing on socket suspension using mechanical loading. NUPOC Biennial Symposium for Initiative ’93, March 13, Chicago, IL.

Quinlan J, Tran L, Yohay J, Poziembo B, Fatone S (2017) The effect of prosthetic socket texturing on socket suspension using mechanical loading. Midwest Chapter of the American Academy of Orthotists and Prosthetists, November 11, Chicago, IL.