Artificial Knee Joint Locking Mechanism for Reduced Insertion Force
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional artificial knee joint replacements, particularly those using dovetail-type locking mechanisms, require excessive force for fastening and separation, and are not well-suited for patient customization or resistance against the natural load direction during walking, leading to potential displacement and discomfort.
Innovation Solution
An artificial knee joint replacement with a modified dovetail locking mechanism featuring protrusions on the tibial component and corresponding grooves on the bearing component, allowing for secure fastening and separation with reduced resistance and enabling customization, while providing strong resistance against the natural load direction during walking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a dovetail-type locking mechanism is used to fasten the bearing component to the tibial component, then fastening stability is improved, but excessive force is required for fastening and separation
Solution Approach 1:
The locking mechanism is divided into multiple segments: a locking protrusion with a locking portion and a groove with a groove bottom. The groove bottom acts as an intermediary that receives and redistributes the fastening force, segmenting the force transmission path to reduce peak forces while maintaining stability.
Solution Approach 2:
The groove bottom serves as an intermediary element between the locking protrusion and the bearing component. It receives the fastening force from the locking protrusion and transmits it to the bearing component, facilitating easier fastening and separation while maintaining secure connection.
2Stability of the object's composition
If the bearing component is designed to resist load from front to rear, then structural symmetry is maintained, but it cannot effectively resist the natural load direction during walking
Solution Approach 1:
The locking protrusion is designed with asymmetric geometry where the locking portion extends preferentially in the front-to-rear direction. This asymmetric structure provides superior resistance against loads applied in the natural walking direction while maintaining compatibility with patient-specific anatomical variations through adjustable positioning.
3Stability of the object's composition
If hooks are engaged and coupled to resist leverage forces, then fastening stability is improved, but the front hook gets caught making separation very difficult
Solution Approach 1:
The harmful leverage effect that causes hooks to get caught is extracted and replaced by a groove bottom structure. The groove bottom provides a controlled engagement point that prevents the locking protrusion from getting caught, enabling easy separation while maintaining fastening stability during use.
4Ease of operation
If a pin is inserted to couple components, then ease of separation is improved, but structural complexity increases
Solution Approach 1:
The fastening and separation functions are merged into a single integrated locking protrusion-groove mechanism. The locking protrusion simultaneously provides stable fastening through its locking portion and enables easy separation through its interaction with the groove bottom, eliminating the need for separate pins or additional components.
Data Source
AI summary
Proposed is an artificial knee joint replacement. The artificial knee joint replacement includes a tibial component directly fixed to a bone resection surface of tibia and configured to have a protrusion portion protruding from an upper fastening surface thereof, and a bearing component interposed between a femoral component directly fixed to a bone resection surface of femur and the tibial component, and configured to have an accommodation portion formed on a lower fastening surface thereof to correspond to the protrusion portion, wherein the protrusion portion consists of two protrusions spaced apart from each other along a first direction reference line of the tibial component, and the accommodation portion consists of grooves formed in a structure that is continuous with each other along a first direction reference line of the bearing component.