Adjustable Spinal Interbody Implant With Wedge-Driven Expansion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing expandable interbody devices have limited expansion ranges and instability issues, leading to subsidence of spinal surfaces and undesired shifts during implant expansion, with challenges posed by anatomical features like the iliac crest and rib cage.
Innovation Solution
A highly adjustable interbody device with a moving mechanism that allows for selective adjustment of spacing and angle between endplates, using set screws and sliding frames to expand or contract, and rotate for precise positioning.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If existing expandable interbody devices are used, then the device can be introduced in a collapsed state and expanded to produce spacing, but the expansion range is limited
Solution Approach 1:
The interbody device is divided into multiple expandable segments or struts that can be independently controlled. Each segment contains its own expansion mechanism, allowing differential expansion to achieve complex spatial configurations and extended expansion ranges beyond what single-segment designs permit.
Solution Approach 2:
The device transitions from a static structure to a dynamic, adjustable configuration. The expansion mechanisms allow the device to change its shape and size during the surgical procedure, enabling real-time adaptation to different anatomical spaces and patient-specific requirements.
2Reliability
If existing interbody devices are used, then they can provide stability, but subsidence of spinal surfaces occurs due to inadequately-sized load-bearing surfaces
Solution Approach 1:
The load-bearing surfaces are merged with the expansion mechanism. As the device expands, the load-bearing surfaces are simultaneously enlarged to match the increased footprint, ensuring that the additional surface area is available to distribute and bear the mechanical loads generated during expansion and subsequent use.
Solution Approach 2:
The load-bearing surfaces are pre-configured to expand simultaneously with the main device structure. This preliminary coordination ensures that adequate surface area is established before full expansion occurs, preventing subsidence by ensuring sufficient load distribution from the outset.
3Length of moving object
If existing expandable interbody devices are expanded, then spacing is produced, but load-bearing surfaces move relative to one another causing instability
Solution Approach 1:
The expansion mechanism employs asymmetric design elements that allow controlled differential expansion of different segments. This asymmetric control enables precise adjustment of spacing while maintaining stable relative positioning of load-bearing surfaces through strategically placed locking features and guide structures.
Solution Approach 2:
The device incorporates feedback mechanisms that monitor and control the expansion process. As the device expands, the system provides real-time feedback to ensure load-bearing surfaces remain properly aligned and stable, allowing for immediate correction of any unwanted movement or misalignment during the expansion sequence.
Data Source
AI summary
Expandable spinal implants, systems and methods are disclosed. An expandable spinal implant may include a first endplate, a second endplate, and a moving mechanism that is operably coupled to the first and second endplates. The moving mechanism may include a wedge, a first sliding frame and a second sliding frame disposed on opposite sides of the wedge, a screw guide housing a rotatable first set screw and a rotatable second set screw opposite the first set screw. The first set screw may be operably coupled to the second sliding frame and the second set screw may be operably coupled to the wedge. The moving mechanism may operably adjust a spacing between the first and second endplates upon simultaneous rotation of the first and second set screws and operably adjust an angle of inclination between the first and second endplates upon translating the first set screw or second set screw.