Shoulder Joint Replacement Member with Chamfered Glenoid Edge
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Shoulder joint replacements often suffer from limited range of motion in adduction due to impingement issues, leading to discomfort and increased risk of dislocation, particularly in anatomical configurations where the humerus abuts the glenoid replacement, causing wear and osteolysis.
Innovation Solution
A shoulder joint replacement member with a concave joint surface and a chamfered or rounded edge connecting it to a circumferential face, allowing for clearance between the replacement member and the counterpart member even in extreme adduction positions, thereby preventing impingement and enhancing load distribution and longevity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If an anatomical shoulder replacement is used, then the joint structure resembles the natural shoulder, but the range of motion in adduction is limited due to impingement between the humerus and glenoid component
Solution Approach 1:
The patent applies dimensionality change by modifying the glenoid component geometry to include a chamfered or rounded edge at the caudal portion, creating an additional spatial dimension for clearance. This geometric modification in the vertical dimension allows the humeral component to move closer to the glenoid without causing impingement, thereby increasing the range of motion in adduction while maintaining the anatomical appearance of the joint structure.
Solution Approach 2:
The patent employs parameter changes by altering the shape parameters of the glenoid component, specifically introducing a chamfered or rounded edge with defined angles and radii. This parameter modification changes the contact geometry between the humeral and glenoid components, allowing for greater adduction motion while preventing soft tissue impingement and maintaining anatomical resemblance.
2Ease of operation
If reverse shoulder prosthesis with eccentric glenosphere is used, then the range of motion for adduction is extended, but impingement during adduction may still occur and dislocation risk remains
Solution Approach 1:
The patent introduces an intermediary geometric feature - the chamfered or rounded edge - that acts as a mediator between the humeral and glenoid components. This intermediate structure prevents direct contact and impingement of soft tissues during adduction, while also maintaining proper joint alignment and reducing dislocation risk. The chamfered edge serves as a buffer zone that allows increased range of motion without compromising joint stability.
3Reliability
If the effective range of motion is reduced to mitigate impingement risk, then dislocation risk decreases, but the range of motion becomes limited compared to native joint
Solution Approach 1:
The patent applies preliminary action by pre-configuring the glenoid component with a chamfered or rounded edge geometry before implantation. This pre-designed geometric feature proactively creates clearance space that prevents impingement and dislocation before they can occur during joint movement. The preliminary geometric configuration allows the joint to achieve greater range of motion without requiring post-implantation adjustments or restrictions.
Data Source
AI summary
The disclosure relates to a replacement member for a shoulder joint replacement comprising an attachment face on one side of the member, a concave joint surface on a side of the replacement member opposite to the side of the attachment face, and a circumferential face connecting the attachment face and the joint surface. A portion of the concave joint surface is connected to at least a portion of the circumferential face via a chamfered or rounded edge.