Intervertebral Trial Endplate Mapping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Spinal fusion surgeries face challenges with spinal fusion cage subsidence and expulsion due to insufficient contact area and load transfer between vertebral bodies, which can be exacerbated by anatomical variability and low bone mineral density, and existing technologies lack patient-specific intra-operative solutions.
Innovation Solution
An intervertebral trial with an adjustable distal end portion and imaging features that map vertebral endplate contours using light or ultrasound waves to create a 3D image, allowing for the fabrication of patient-specific implants with enhanced contact area and customized geometry.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If a fixed-shaped cage is used to maximize contact area, then load transfer is improved, but anatomical variability prevents proper conformance to each disc space
Solution Approach 1:
The trial device incorporates an adjustable height mechanism that allows the distal end portion to be dynamically repositioned within the disc space. This dynamic adjustment capability enables the cage to adapt to varying anatomical configurations while maintaining optimal contact area with the vertebral endplates, resolving the contradiction between fixed geometry and anatomical variability.
Solution Approach 2:
The trial device features a contoured distal end portion with imaging capabilities that map the specific geometry of each vertebral endplate. This localized customization approach allows the cage to conform precisely to the unique anatomical features of each patient's disc space while maintaining sufficient contact area for load transfer.
2Manufacturing precision
If preoperative imaging data is used to manufacture patient-specific devices, then anatomical precision is improved, but the assumption of correct disc space geometry prior to surgical intervention is limiting
Solution Approach 1:
The trial device integrates imaging features that map the contour of vertebral endplates during the surgical procedure itself. This preliminary intra-operative mapping action provides real-time anatomical data without requiring preoperative CT or MRI-derived geometry assumptions, enabling patient-specific customization while maintaining surgical flexibility.
Solution Approach 2:
The trial device serves as an intermediary tool that bridges the gap between preoperative planning and final implant placement. By incorporating imaging capabilities and adjustable geometry, it mediates between the need for patient-specific precision and the requirement for intra-operative adaptability, allowing surgeons to verify and adjust disc space geometry before final implantation.
3Area of stationary object
If the cage is made larger to maximize footprint, then contact area is improved, but the cage may not fit within the disc space
Solution Approach 1:
The trial device is divided into distinct segments including an adjustable distal end portion and a proximal end portion. This segmentation allows the distal end to be optimized for maximum contact area with the vertebral endplates while the proximal portion can be adjusted to fit within the constraints of the disc space, resolving the contradiction between size and fit.
Solution Approach 2:
The adjustable height mechanism allows the cage to dynamically change its dimensions to maximize contact area at the distal end while maintaining appropriate overall size for disc space accommodation. The distal end portion can be extended to achieve optimal footprint while the proximal portion adjusts to fit within the available space.
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 secure placement of implants, reducing the risk of subsidence and expulsion by providing a tailored solution to individual anatomical variations, thereby improving surgical outcomes.
Implementation Method 1
mapping features adapted to map a contour of a vertebral endplate, such as light or ultrasound waves adapted to emit waves into a space between the trial and the vertebral endplate to create a three-dimensional image of the cavity between the trial and the vertebral endplate
Implementation Method 2
mapping features adapted to map a contour of a vertebral endplate, such as light or ultrasound waves adapted to emit waves into a space between the trial and the vertebral endplate to create a three-dimensional image of the cavity between the trial and the vertebral endplate
Data Source
Figure 1A~1B
Figure 2A~2B
Figure 3A~3F
AI summary
A method of determining disc space geometry with the use of an expandable trial having endplate-mapping capabilities. An expandable trial is inserted into the disc space and its height is adjusted to obtain the desired decompression and spinal alignment (which is typically confirmed with the use of CT or Fluoroscopic imaging). The endplate dome/geometry dome is then determined by one of the following three methods: a) direct imaging through the trial, b) balloon moldings filled with flowable in-situ fluid (for example, silicon, polyurethane, or PMMA) from superior/inferior endplates or c) light-based imaging through superior & inferior balloons.