The Söderberg Socket 2.0: A Technical Note

Abstract
BACKGROUND: Transtibial prosthesis socket trim lines have remained fairly consistent over the past decade, and based on methods such as a supracondylar cuff suspension. However, with vacuum suspension methods, trim lines can change. OBJECTIVE: An objective of this technical note was to inform practitioners how to fabricate a socket in a better way. A step-by-step fabrication guide is provided for the prosthetist. METHODS: A unilateral transtibial amputee was selected for this technical note. We provide a detailed description of the different steps of fabrication as well as patient feedback. The fabrication involved fabrication of a vacuum socket using Pre-preg carbon fiber and anti-bacterial Ethylene-Vinyl-Acetate (EVA), as a proximal flexible brim. FINDINGS: The properties of EVA and Pre-preg carbon fiber allow for fabrication of a transtibial socket with a flexible proximal brim. The new design resulted in greater comfort and increased range of motion in the patient studied. The patient subjectively noted enhanced squatting and cycling capabilities while using the updated socket and flexible proximal brim. CONCLUSION: This technical note presented a fabrication guide for a new style of socket and preliminary patient feedback. Clinical studies evaluating functional and biomechanical effects of this new socket design are needed. Layman’s abstract: The lower limb prosthetic socket is crucial for comfort and function of a lower limb amputee. A socket which is well-fitting and which adjusts to the user’s unique needs is an important shared goal for the prosthetist and user. Traditional types of prosthetic sockets might not always fit the needs of the user. Our patient desired a socket that would allow him to bend his knee in a greater range of motion than a traditional type of socket was permitting him to do. We provided a prosthetic socket which had a flexible top portion that could allow a greater range of motion and vacuum suction suspension with his limb. This socket combined a flexible type material with a specialty carbon fiber to meet the patient’s needs. These two technical improvements to his socket evidenced a reported increase in recreational activity of the patient. Future work can evaluate the underlying biomechanical mechanisms during walking and recreational activities for patients fit with our style of socket. This work could further our understanding of patient function in the studied prosthetic socket. Article PDF Link: https://jps.library.utoronto.ca/index.php/cpoj/article/view/33505/25944 How to Cite: Söderberg B, Guerra G, Fagerstrom T, Permpool K, Phaipool S. The Söderberg socket 2.0: A technical note. Canadian Prosthetics & Orthotics Journal. 2019;Volume2, Issue2, No.3. https://doi.org/10.33137/cpoj.v2i2.33505 CORRESPONDING AUTHOR:Gary Guerra, Ph.D Sirindhorn School of Prosthetics and Orthotics, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand. Email: gary.gue@mahidol.edu ORCID: https://orcid.org/0000-0002-0161-4616