Bone Implant Augment With Undercut For Cement Fixation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional bone implants face challenges in achieving stable cement fixation, which is crucial for the long-term success and stability of the implant.
Innovation Solution
The augment for a bone implant features a body with specific interfaces for fastening to the bone implant and the bone, along with an undercut at the interface to a fastening element. This design incorporates a rough surface for improved cement fixation and a tapered body to facilitate manufacturing and reduce unnecessary rough surfaces.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional augments are used without an undercut, then the manufacturing process is simpler, but cement fixation is insufficient
Solution Approach 1:
The patent applies a conical or concave undercut geometry at the interface to the fastening element. This curved/angled geometry creates mechanical interlocking with the bone cement, significantly improving cement fixation reliability compared to flat surfaces, while remaining manufacturable through standard forming processes
2Reliability
If the body extends perpendicular to the interface plane, then manufacturing is easier, but cement fixation area is reduced
Solution Approach 1:
The patent applies different geometries to different regions: the body extends perpendicular to the interface plane for most of its length (simplifying manufacturing), but includes a localized undercut region with conical or concave geometry (improving cement fixation). This local differentiation optimizes both fixation and manufacturability without requiring complex overall geometry
3Reliability
If rough surfaces are provided on all surfaces, then cement fixation is improved, but manufacturing complexity increases and unnecessary rough surfaces are created
Solution Approach 1:
The patent provides rough surfaces specifically at the interface to the fastening element where cement fixation is needed, while maintaining smooth surfaces on other portions of the body. This localized roughness application improves cement fixation reliability without unnecessarily complicating the manufacturing of non-cement-contact surfaces
Data Source
AI summary
An augment for a bone implant, in particular for a tibia or a femur, has a body. The body has an interface for fastening the augment to a plateau of the bone implant, an interface for fastening the augment to the bone, and an interface to a fastening element for anchoring the bone implant in a medullary cavity of a bone, which extends between the interface for fastening the augment to the plateau and the interface for fastening the augment to the bone. The body has an undercut at the interface to the fastening element. The augment can be part of a set of augments.