Expandable Vertebral Body Replacement With Locking Ring Expansion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing spinal surgeries face challenges in minimizing surgical trauma while ensuring adequate support and fusion between vertebrae, as small access ports restrict the size of implants that can be used, and existing expandable interbodies lack efficient expansion mechanisms.
Innovation Solution
An expandable interbody device with inner and outer columns that translate vertically via an expansion ring, allowing for controlled expansion and stabilization, featuring a locking mechanism and modular endplates for adjustable lordosis, facilitated by a dedicated insertion/expansion tool.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a small access port is used to minimize surgical trauma, then surgical trauma is reduced, but the size of tools and implants that can pass through is limited
Solution Approach 1:
The interbody device transitions from a static structure to a dynamic one that can change size. It is inserted in a compressed state through the small access port and then expanded in situ to the desired size, allowing the implant to adapt to different patient requirements while maintaining minimal invasive access
Solution Approach 2:
The interbody device utilizes a nested configuration where the inner column is positioned within the outer column during insertion. This nested structure allows the implant to be compact enough for small access ports while providing sufficient volume when expanded to support fusion
2Volume of moving object
If expandable interbodies are used to achieve desired size in disc space, then implant size is optimized, but the expansion mechanism becomes more complex
Solution Approach 1:
The expansion mechanism is divided into discrete functional segments: the inner column, outer column, and expansion ring. Each component has a specific function, and their modular arrangement simplifies the overall expansion process while maintaining reliability
Solution Approach 2:
The device incorporates a self-locking mechanism where the locking arms automatically engage with the expansion ring teeth when the inner column is inserted, eliminating the need for additional locking components and simplifying the expansion system
3Stability of the object's composition
If locking arms are added to prevent rotation of expansion ring, then stability is improved, but device complexity increases
Solution Approach 1:
The locking function is merged into the expansion ring structure itself through integrated locking arms that are part of the ring assembly. This integration eliminates separate locking mechanisms and reduces overall device complexity while maintaining rotational stability
Solution Approach 2:
The locking arms automatically engage with the expansion ring teeth when the inner column is inserted, providing self-locking functionality without requiring additional actuators or complex control systems
Data Source
AI summary
An expandable interbody with a modular endplate has an outer column, an inner column threadedly coupled and translatable relative to the outer column along the longitudinal axis, and an expansion ring to adjust a body length of the expandable interbody. The expansion ring has a plurality of teeth, and the outer column has at least one arm for engaging a tooth of the plurality of teeth to lock the expansion ring. The inner column and/or outer column can include a connector for connection to a modular endplate that has a substantially hollow core. The modular endplate includes a plate with a set screw entrapped therein. The modular endplate has an aperture to receive the connector of the inner and/or outer column.