(L-475) Comparison of Pressure Values in Two Donning Methods for Residual Limb Shrinkers

Introduction:: Each year in the United States, approximately 150,000 people will have a major lower limb amputation (i.e., through ankle and above) [1]. Compression garments are applied to the residual limb to enhance blood circulation to the residual limb, reduce excess inflammation, and shape the limb so that it can be successfully fit with a prosthesis. Residual limb shrinkers are the best option because of uniform pressure distribution once applied, but can be challenging and painful to don. The shrinker can be donned by two people or by using a donning tube, but the pressure distribution applied to the limb during application of the shrinker is relatively unstudied. Considering the pain that is often associated with donning the residual limb shrinker, but recognizing the importance to healing, it is necessary to find the best method of applying a shrinker. The purpose of this study was to find the pressure distribution on a model residual limb when applying a residual limb shrinker with two different donning methods.



Materials and Methods:: A model of a transtibial residual lower limb was created using a leg cast, by molding Dragonskin® silicone around a Synbone® left leg bone model. The Synbone® tibia model was placed slightly anterior of center to mimic the anatomy of the lower left residual limb. The pressure at the bottom of the model was mapped radially at 45° every 2 inches starting from the center. The sides of the model were radially mapped every 30° with a vertical 2-inch separation, as shown in Figure 1. The two-person and donning tube methods were performed by physical therapy students. Pressure data was measured using a Flexiforce A201 sensor and collected via an Arduino breadboard. Donning methods were performed twice, and the results were averaged.


Results, Conclusions, and Discussions:: This study found that the donning tube method applied less pressure than the two-handed donning method on average. The two-person method (labeled as “Hands” in Table 1) had a greater standard deviation (SD) and application pressure overall compared to the donning tube method (Table 1). Outlier pressure values in may have occurred due to uncontrolled wrinkling of the limb shrinker due to limited silicone above the knee joint.

The donning tube method provided lower application pressure than the two-person method. The initial results from this study are promising and may aide in residual limb shrinker compliance because of lower pressures than the two-person method, since the donning tube method can be performed by one person and is easy to learn. The study was done with a transtibial residual limb model and equating pressure to pain. Future studies will incorporate transfemoral models and then pressure measurements with subjects who had a lower limb amputation.


Acknowledgements (Optional): : We acknowledge support from Shane Coltrain CPO (owner of Orthotics and Prosthetics East) who co-funded this research along with East Carolina University Department of Engineering. A special thank you to ECU Physical Therapy students: Ashley Arensdorf and Paxton Dettor.

References (Optional): : [1] Molina , C. S., & Faulk, J. B. (2022, August 22). Lower extremity amputation. National Center for Biotechnology Information. Retrieved April 25, 2023, from https://pubmed.ncbi.nlm.nih.gov/31536201/