Convert Shoulder Prosthesis Fixation Ring Without Bone Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current shoulder replacement prostheses face challenges in converting from anatomic to reverse configurations without disrupting the fixation components, especially in cases where the glenoid fossa is small and bone presence is reduced, leading to instability and potential failure.
Innovation Solution
A method and system for reversible anatomic shoulder replacement, involving the use of an anatomic glenoid articular implant with a central peg and intermediate component attached to a snap ring and fixation ring, allowing for conversion to a reverse shoulder prosthesis without removing the fixation components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If an anatomic prosthesis is used initially, then the shoulder replacement provides effective treatment, but over time the rotator cuff becomes insufficient requiring a second operation to convert to reverse prosthesis
Solution Approach 1:
The prosthesis is divided into separate components: a fixation component that remains in the glenoid fossa and an articular component that can be exchanged. This segmentation allows the fixation component to maintain stable anchorage while the articular component can be replaced to convert from anatomic to reverse configuration, resolving the contradiction between fixation stability and convertibility.
Solution Approach 2:
The system transitions from a static, fixed configuration to a dynamic, exchangeable configuration. The modular design with interchangeable articular components enables the prosthesis to adapt over time, allowing conversion from anatomic to reverse configuration based on changing clinical needs while maintaining the same fixation structure.
2Strength
If the glenoid fossa is small with reduced bone presence, then the fixation space is limited, but the prosthesis requires sufficient fixation area for stability
Solution Approach 1:
The fixation component is designed with localized features that concentrate fixation strength in specific areas of the glenoid fossa. The component geometry and surface characteristics are optimized to maximize fixation strength in the limited available bone area, addressing the contradiction between required fixation strength and limited bone area.
3Device complexity
If the prosthesis is designed to be thin to fit the joint, then the articulating surface is compact, but there is insufficient space for attachment mechanisms
Solution Approach 1:
The attachment mechanisms are nested within the thickness of the articular component itself, rather than requiring additional external space. The modular interface is integrated into the component design, allowing exchange capability without increasing the overall profile or complexity of the thin prosthesis structure.
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
Enables the conversion of anatomic to reverse shoulder prostheses while maintaining the stability of the fixation components, reducing the risk of instability, soft tissue failure, and implant failure, and allowing for effective use of remaining muscle structures.
Implementation Method 1
a fixation ring at least partially comprising a porous surface
Data Source
AI summary
Disclosed are prosthesis systems and methods that provide porous fixation rings by which the articulating surfaces of the implant can be exchanged such that the anatomic surfaces can be converted to reverse surfaces, while not exchanging the fixation components. Also disclosed herein are methods by which the surgeon can implant an inset anatomic articulating glenoid implant whereby at a later date, can remove the anatomic articulating surface and replace it with a reverse articulating surface such that the primary means of fixation remains well fixed in the glenoid fossa at the moment of articular exchange.