Prosthesis Socket Sealing Lip Vacuum Fixation
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Solution Overview
Problem
Prosthesis socket systems with flexible inner sockets face challenges in achieving a secure and comfortable hold on the residual limb while accommodating volume fluctuations and bony structures, often requiring additional components like cuffs and liners for effective vacuum fixation.
Innovation Solution
A prosthesis socket system with a rigid outer socket and a flexible inner socket featuring a sealing lip that creates a vacuum seal, eliminating the need for external cuffs and allowing for easy application and wear, suitable for various residual limb shapes and sizes, including oval and irregular cross-sections, with optional windows for pressure relief and adjustable inserts for enhanced comfort.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a flexible inner socket is used to accommodate volume fluctuations of the residual limb, then adaptability is improved, but achieving a secure vacuum seal becomes more difficult
Solution Approach 1:
The sealing lip is designed with specific local properties - it has a rounded free end that contacts the skin, and its thickness varies along its length (thinner at the free end, thicker at the connection to the inner socket). This local differentiation allows the sealing lip to effectively seal against the irregular surface of the residual limb while maintaining vacuum integrity, resolving the contradiction between adaptability and seal reliability.
Solution Approach 2:
The sealing lip is made from flexible material that can deform and conform to the irregular shape of the residual limb surface. This flexibility allows the sealing lip to adapt to volume changes and anatomical variations while maintaining continuous contact for effective sealing, thus achieving both adaptability and reliable vacuum seal.
2Reliability
If additional components like cuffs and liners are added to achieve secure vacuum fixation, then fixation reliability is improved, but device complexity increases
Solution Approach 1:
The sealing lip integrates multiple functions into a single component: it provides the vacuum seal, accommodates the interface between inner and outer sockets, and ensures secure fixation. By combining these functions that previously required separate components (cuffs, liners, sealing elements), the design achieves reliable vacuum fixation while minimizing device complexity.
Solution Approach 2:
The sealing lip serves multiple purposes simultaneously: it creates the vacuum seal against the residual limb, provides the connection interface between inner and outer sockets, and ensures secure fixation. This multi-functionality eliminates the need for additional specialized components, reducing overall system complexity while maintaining fixation reliability.
3Adaptability or versatility
If the inner socket is made entirely flexible to accommodate residual limb shape, then adaptability is improved, but structural stability deteriorates
Solution Approach 1:
The prosthesis system uses a composite structure combining flexible inner socket material with a rigid outer socket. The flexible inner socket provides adaptability to the residual limb shape, while the rigid outer socket maintains structural stability. The sealing lip acts as an interface between these two material systems, allowing them to work together effectively.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system provides a secure, comfortable, and lightweight prosthesis with improved stability and adaptability, allowing for secure fixation without external cuffs, accommodating volume changes and bony structures, and enhancing user experience through adjustable components and flexible materials.
Implementation Method 1
a vacuum is usually created between the inner socket and the residual limb
Implementation Method 2
at least one sealing lip is arranged on an inner surface of the inner socket facing the residual limb
Data Source
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AI summary
The invention relates to a prosthesis shaft system with a rigid outer shaft (10) which has a proximal outer shaft opening (14) for receiving an extremity stump of a wearer of the prosthesis shaft system, and a flexible inner shaft (20), which is connected to the outer shaft (10), and has a proximal inner shaft opening (24) for receiving the extremity stump, wherein at least one sealing lip (26) is arranged on an inner side of the inner shaft (20) facing the extremity stump.