Ramp-Driven Expandable Fusion Device for Disc-Space Matching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional intervertebral fusion devices require vertebral body distraction for installation, leading to difficulties in fitting due to height discrepancies between the distracted and natural disc space.
Innovation Solution
An expandable fusion device with endplates and central and driving ramps that can be inserted without distraction, allowing expansion to maintain normal disc spacing and stabilize the spine.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If conventional fusion devices are used, then vertebral bodies can be fused, but the devices require pre-distraction of vertebral bodies for installation which creates height discrepancy difficulties
Solution Approach 1:
The fusion device incorporates an expandable mechanism with a body portion and endplates that can transition from a compressed insertion state to an expanded functional state. The endplates are movable relative to the body portion, allowing the device to adapt its height to match the natural disc space without requiring pre-distraction of vertebral bodies, thereby simplifying the installation procedure while maintaining fusion capability
2Stability of the object's composition
If fusion devices are dimensioned larger in height than distraction height, then normal disc spacing can be maintained, but installation becomes difficult in distracted intervertebral space
Solution Approach 1:
The device enables dynamic adjustment of its height through the expandable endplate mechanism. During insertion, the endplates are in a compressed position allowing passage through the disc space, then they can be expanded to the desired height to maintain normal disc spacing, eliminating the need for pre-distriction while ensuring proper spacing maintenance
Solution Approach 2:
The device is prepared in a pre-compressed configuration for insertion, and the expansion to full height is performed as a preliminary action before final positioning and fixation. This allows the device to be inserted in a compact form and then expanded to achieve the required disc spacing without requiring the vertebral bodies to be distracted during installation
Data Source
AI summary
The present invention provides an expandable fusion device capable of being installed inside an intervertebral disc space to maintain normal disc spacing and restore spinal stability, thereby facilitating an intervertebral fusion. In one embodiment, the fusion device includes body, a first endplate, and a second endplate, a middle ramp piece, a stem, and two ramp pins. The middle ramped piece is operable to move to generate lordotic expansion of the first and second endplates followed by parallel expansion. The fusion device is operable to be deployed down an endoscopic tube.