Prosthesis Socket Casting with Weight-Responsive Fluid Pressure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing prosthesis casting devices using the hydrostatic principle can cause tissue distortion and discomfort due to manual tensioning mechanisms, and are difficult to remove after the casting process.
Innovation Solution
A prosthesis socket casting device with a flexible membrane and a piston assembly that adjusts fluid pressure based on the patient's weight, incorporating a braided sleeve and telescoping housing for easy insertion and removal, and a collapsible design for portability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a manual tensioning mechanism (spring) is used to pull on the residuum, then tissue distortion is reduced, but the risk of excess tensioning causing pain and discomfort increases
Solution Approach 1:
The piston assembly automatically adjusts tension based on the patient's body weight, eliminating the need for manual adjustment. The system self-regulates by converting the patient's weight into a controlled downward force on the residuum through fluid pressure, ensuring consistent and safe tensioning without risk of excess force application.
Solution Approach 2:
The manual spring-based mechanical tensioning system is replaced with a fluid pressure-based system. The piston assembly uses hydraulic or pneumatic pressure generated by the patient's weight to provide controlled tension, substituting complex manual mechanical adjustment with a simpler, self-regulating fluid pressure mechanism.
2Stability of the object's composition
If the housing is rigid and fixed, then structural stability is maintained, but ease of removal of residuum is reduced
Solution Approach 1:
The housing transitions from a static, fixed structure to a dynamic, adjustable structure. The telescoping sections allow the housing to change its configuration - extending for stable casting and collapsing for easy removal - adapting the structural properties to the operational requirements at each stage.
Solution Approach 2:
The housing is divided into multiple telescoping sections that can move relative to each other. This segmentation allows the housing to be collapsed into a compact configuration for easy removal of the residuum, while maintaining structural integrity when extended for the casting process.
3Strength
If the device is non-collapsible, then structural integrity is maintained, but portability and ease of storage are reduced
Solution Approach 1:
The housing structure is made dynamic through telescoping sections that can extend to maintain structural integrity during use and collapse to a compact form for portability and storage. This allows the same structure to satisfy both strength requirements during operation and portability requirements during transport.
Solution Approach 2:
The telescoping housing sections are nested within each other, with smaller sections fitting inside larger ones. This nesting arrangement allows the device to collapse into a compact, space-efficient configuration for portability while maintaining full structural capability when extended for the casting process.
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
Reduces tissue distortion and discomfort by automatically adjusting fluid pressure, facilitates easy residual limb removal, and ensures consistent, high-quality socket fitting.
Implementation Method 1
casting device for producing a prosthetic socket, for persons with a lower-limb amputation, according the hydrostatic principle
Implementation Method 2
the fluid or gas to support the residual limb and conform to its 'ideal' shape by exerting a supporting loading condition (pressure)
Implementation Method 3
the effective force applied to the end of the stump may be altered, in particular the force may be reduced and the lateral retaining force applied to the sides of the stump may be increased
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
A prosthesis socket casting device having a housing and a flexible membrane for receiving a residual limb, the housing and the membrane defining a cavity for containing a fluid. Within the housing are means that are a function of the patient's weight for altering the distribution of the reactive fluid pressure applied when the residual limb is received within the membrane. In a preferred embodiment, the altering means comprise a movable piston that is provided at a lower end of the housing.