Intervertebral Implant Multi-Radius Articulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing intervertebral disc implants with single radius articulation surfaces require precise placement to maximize mobility, which is challenging and can lead to restricted motion segment movement and associated pain or accelerated degeneration.
Innovation Solution
The design incorporates upper and lower implant bodies with dome-shaped surfaces defined by different radii, along with an insert assembly that articulates along these surfaces, allowing for a range of motion that mimics natural spinal movement while accommodating misalignment, thereby reducing wear and improving placement accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single radius articulation surface is used, then the implant structure is simple, but precise placement is required to maximize mobility
Solution Approach 1:
The articulation surface is segmented into multiple zones with different radii (first radius and second radius) instead of using a single radius. This segmentation allows each zone to accommodate different placement scenarios, reducing the overall placement precision requirement while maintaining mobility functionality.
Solution Approach 2:
The patent changes the geometric parameter of the articulation surface from a single radius to multiple radii. By varying the radius parameter across different zones, the implant can accommodate a range of placement positions while maintaining optimal articulation and mobility.
2Reliability
If precise placement is required, then mobility is maximized, but placement difficulty increases
Solution Approach 1:
The articulation surface is divided into multiple radial zones that can accommodate different placement positions. This segmentation provides a more forgiving placement window, making the procedure easier while still achieving reliable mobility through proper articulation at any of the acceptable zones.
Solution Approach 2:
Instead of requiring precise placement at a single optimal position, the design provides excessive articulation surface coverage with multiple radii. This partial action approach allows the implant to function reliably even with approximate placement, reducing the difficulty of the surgical procedure.
3Device complexity
If single radius articulation is used, then the implant design is simple, but motion segment movement may be restricted
Solution Approach 1:
The articulation surface is segmented into multiple radial zones with different curvature radii. This segmentation enables the implant to accommodate various motion patterns and placement scenarios, maintaining ease of operation and motion segment mobility without significantly complicating the overall implant design.
Solution Approach 2:
The multi-radius articulation surface provides dynamic adaptability to different motion requirements. The varying radii allow the implant to naturally accommodate different ranges of motion and articulation patterns, enhancing ease of operation while keeping the design relatively simple.
Data Source
AI summary
An intervertebral implant comprises a number of components including upper and lower endplates and one or more inserts configured to be disposed between the upper and lower endplates. Complimentary curved articulation surfaces are defined on the insert-facing surfaces of the upper and lower endplates and on the corresponding upper and lower surfaces of each of the inserts. The components of the implant articulate with respect to each other along shared articulation surfaces. At least two pairs of shared articulation surfaces are defined, each pair having a different length radius. The components of the implant can be configured with retainers, such that the implant is retained in an assembled configuration when disposed within an intervertebral space.