Expandable Spinal Cage with Slidable Hinge for Lordosis Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current spinal implants face challenges in accommodating varying anatomical configurations, as they often require a larger implant to be inserted in a smaller configuration and adjusted in situ, which is difficult due to anatomical differences between individuals.
Innovation Solution
An expandable spinal cage with a slidably supported hinge, actuated by a plate mover and biased support members, allowing for controlled expansion and rotation to fit the anatomy, including keels for proper orientation and inner ramps for tilting, enabling adjustment of the lordosis angle between vertebrae.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a larger implant is used to accommodate varying anatomical configurations, then adaptability to different anatomies is improved, but ease of insertion is worsened due to the difficulty of placing a bigger implant in a confined space
Solution Approach 1:
The implant is divided into multiple segments including first and second support plates connected by a hinge, with a plate mover positioned between them. This segmentation allows the implant to be inserted in a compact state and then expanded in situ to accommodate different anatomical configurations, resolving the contradiction between adaptability and ease of insertion.
Solution Approach 2:
The implant incorporates dynamic components including a slidable hinge and an actuated plate mover that enable the structure to transition from a compressed insertion configuration to an expanded operational configuration. This dynamic capability allows the implant to adapt to varying anatomical spaces while maintaining ease of insertion through controlled expansion after placement.
2Adaptability or versatility
If the implant is designed to be adjusted in situ, then adaptability to individual anatomy is improved, but device complexity is worsened due to the additional adjustment mechanisms required
Solution Approach 1:
The plate mover is nested between the first and second support plates, with the hinge journaled in an elongate aperture formed in a hinge housing protruding from the first support plate. This nested arrangement allows multiple functional components to be integrated in a compact manner, providing adjustability without proportionally increasing overall device complexity.
Solution Approach 2:
The hinge acts as an intermediary mechanism between the support plates, enabling rotational movement and angle adjustment. The elongate aperture in the hinge housing serves as an intermediary structure that guides and constrains the hinge movement, providing controlled adjustability while simplifying the overall mechanism compared to direct plate-to-plate adjustment.
3Adaptability or versatility
If a hinge with elongate aperture is used to allow translation and rotation, then adaptability of the implant configuration is improved, but manufacturing precision is worsened due to the need for precise journaling in the elongate aperture
Solution Approach 1:
The hinge is designed to move within an elongate aperture that allows for parameter changes in position and orientation. The aperture's geometry is specifically designed to guide the hinge through predetermined translational and rotational paths, enabling configurability while the manufacturing precision requirements are managed through the controlled geometry of the aperture rather than requiring high-precision bearings or joints.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables precise fitting and adjustment of the spinal cage to match individual anatomical needs, facilitating effective spinal stabilization and lordosis control post-installation.
Implementation Method 1
The hinge is free to translate and rotate in the elongate aperture
Implementation Method 2
the plate mover being arranged to slide against an inclined surface on the first support plate
Implementation Method 3
one or more support members are biased towards the hinge and/or the first support plate. The one or more support members may be biased by a biasing device
Data Source
AI summary
A spinal cage includes a first support plate pivotally connected to a second support plate by a hinge, and a plate mover actuated by an actuator and located between the first and second support plates. The plate mover is arranged to slide against an inclined surface on the first support plate. A hinge is journaled in an elongate aperture formed in a hinge housing protruding from first support plate, the hinge being free to translate and rotate in the elongate aperture.