Retroversion Glenoid Component Asymmetric Peg Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional glenoid components for shoulder arthroplasty face challenges in positioning and bone removal, particularly in cases of glenoid retroversion, where uneven deterioration requires significant surface preparation or large bone removal, complicating the implant procedure.
Innovation Solution
A retroversion glenoid component kit with a flat bone contacting surface, angled centre peg, and drill guide to facilitate precise positioning and minimize bone removal, featuring a drill guide with angled pegs that match the component's angle, allowing for accurate alignment and reduced bone excision.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional glenoid components are implanted on a level base to achieve proper positioning, then positioning accuracy is improved, but significant bone removal is required in cases of glenoid retroversion
Solution Approach 1:
The glenoid component features an asymmetric design with a center peg axis that forms a specific angle (e.g., 5 degrees) with the bone contacting surface, rather than being perpendicular. This asymmetric geometry allows the component to accommodate retroverted glenoids without requiring extensive bone removal, while still achieving proper positioning and orientation of the articulating surface
Solution Approach 2:
The invention changes the geometric parameters of the glenoid component, specifically the angle between the center peg axis and the bone contacting surface. By adjusting this angle parameter, the component can be adapted to different degrees of retroversion, reducing the need for bone removal while maintaining positioning accuracy
2Manufacturing precision
If bone grafting is used to even out the glenoid fossa for proper implant orientation, then positioning accuracy is improved, but the procedure becomes a two-stage process increasing complexity
Solution Approach 1:
The invention extracts the need for bone grafting by incorporating the angular compensation directly into the glenoid component design. The asymmetric geometry of the component allows it to function on the existing retroverted surface without requiring additional bone grafting procedures, thereby simplifying the surgical approach to a single-stage procedure
Solution Approach 2:
Instead of modifying the bone surface to accommodate a conventional component (adding bone graft), the invention inverts the approach by designing a component that accommodates the existing bone geometry. The component's asymmetric design allows it to be implanted on the retroverted surface as-is, eliminating the need for preparatory bone grafting
3Ease of operation
If the glenoid component uses a perpendicular center peg to the bone surface, then ease of implantation is improved, but positioning accuracy deteriorates in retroverted glenoids
Solution Approach 1:
The center peg is designed with an asymmetric angle relative to the bone contacting surface, forming a specific angle (e.g., 5 degrees) rather than being perpendicular. This asymmetric design maintains ease of implantation through the angled peg while simultaneously achieving accurate positioning by compensating for the retroversion angle, thereby resolving the contradiction between ease of operation and positioning accuracy
Data Source
Figure 1
Figure 2
Figure 3~5
AI summary
A kit for implanting a glenoid component includes a retroversion glenoid component having a generally flat glenoid bone contacting surface defining a first plane. The component has a first offset peg extending away from the glenoid bone contacting surface, a concave articulating surface, an upper surface extending about the concave articulating surface and generally opposite to the glenoid bone contacting surface. The upper surface defines a second plane which is angled with respect to the first plane. The glenoid bone contacting surface defines a circular periphery with the centre peg centred within the circular periphery, and the nadir of the concave articulating surface located on the centre peg axis. A drill guide is configured to guide a drill in forming a bore in a scapula to receive the first offset peg.