Knee-Joint Endoprosthesis Coupling for Ligament-Preserving Implantation
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Solution Overview
Problem
Existing knee joint prostheses require overstretching of ligaments to insert the meniscal component between the tibial and femoral components, compromising the stability of the patient's knee.
Innovation Solution
A coupling device allows the tibial and meniscal components to be coupled in a ligament-preserving manner by enabling a relative movement parallel and perpendicular to a contact plane, facilitating insertion from the front without significant ligament stretching, and allowing easy replacement if necessary.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the meniscal component is inserted between the tibial and femoral components using existing solutions, then the meniscal component can be implanted, but the ligaments must be overstretched which compromises knee stability
Solution Approach 1:
The prosthesis is divided into separate components (tibial component and meniscal component) that can be implanted at different times. The tibial component is implanted first, and the meniscal component is inserted later through a separate insertion opening, eliminating the need to overstretch ligaments during initial implantation.
Solution Approach 2:
The tibial component is implanted and positioned in advance before the meniscal component is inserted. This preliminary action creates the necessary space and structural framework, allowing the meniscal component to be inserted subsequently without requiring ligament overstretching.
2Reliability
If the meniscal component is firmly attached to the tibial component, then stability is improved, but replacement becomes difficult
Solution Approach 1:
The coupling between the meniscal component and tibial component is designed to be dynamically adjustable. The meniscal component can be firmly attached during normal operation for stability, but can be easily detached and replaced when needed through the insertion opening, providing both stability and replaceability.
3Object-affected harmful factors
If the meniscal component is inserted from the front without ligament stretching, then ligament protection is achieved, but a coupling device with multi-directional movement capability is required
Solution Approach 1:
The coupling device acts as an intermediary mechanism between the meniscal component and tibial component. It enables the meniscal component to be inserted from the front through controlled movements (parallel to contact plane, then perpendicular towards each other) without directly stretching the ligaments, protecting them while achieving proper positioning.
Data Source
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AI summary
The invention relates to a knee-joint endoprosthesis device comprising a tibia component, for anchoring on a tibia, and a meniscus component, wherein the tibia component and the meniscus component are coupled to each other in a coupling position and are separated completely from each other in a separation position, which tibia component has an upper face which defines a contact plane and on which an underside of the meniscus component bears in the coupling position, wherein the knee-joint endoprosthesis device comprises a coupling device for coupling the tibia component and the meniscus component in the coupling position, wherein the knee-joint endoprosthesis device is transferrable from the separation position to the coupling position by a relative movement of the tibia component and of the meniscus component. In order to improve said knee-joint endoprosthesis device such the meniscus component and the tibia component can be coupled to each other in a manner preserving the ligaments, it is proposed that the coupling device is designed in such a way that, during the transfer of the knee-joint endoprosthesis device from the separation position to the coupling position, the tibia component and the meniscus component are displaceable relative to each other, in a direction parallel to the contact plane, from the separation position to an intermediate position and are displaceable, towards each other in a direction transverse and in particular perpendicular to the contact plane, from the intermediate position to the coupling position.