Height-Adjustable Intervertebral Fusion Cage Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing intervertebral fusion cages are not easily adjustable in height after insertion, which can lead to suboptimal fixation and increased surgical complexity.
Innovation Solution
The intervertebral fusion cage features a design with movable end plates and a rotatable adjustment member that allows for linear height adjustment between vertebral bodies, enhancing fixation through bone screws.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a fixed-height cage is used, then manufacturing is simple, but the cage cannot be optimally sized for each patient
Solution Approach 1:
The cage incorporates movable end plates that can slide relative to each other along guide portions, transforming the fixed-height structure into a dynamically adjustable one. This allows the cage height to be modified after insertion to match patient-specific requirements while maintaining a relatively simple overall structure.
Solution Approach 2:
The cage is divided into separable components including first and second end plates, movable blocks, and guide portions. This segmentation enables independent adjustment of height while keeping manufacturing of individual components simple, resolving the contradiction between adaptability and manufacturing complexity.
2Adaptability or versatility
If height adjustment mechanism is added, then cage can be optimized for each patient, but surgical procedure becomes more complex
Solution Approach 1:
The dynamic height adjustment mechanism allows surgeons to modify cage height intraoperatively by simply sliding the end plates along the guide portions, without requiring complex tools or procedures. This maintains surgical simplicity while achieving patient-specific optimization.
Solution Approach 2:
The cage structure itself provides the adjustment capability through its integrated guide portions and movable blocks, eliminating the need for external adjustment devices or complex surgical techniques. The system adjusts itself through straightforward mechanical movement.
3Adaptability or versatility
If multiple product variations are manufactured, then patient-specific fit is achieved, but inventory and manufacturing complexity increase
Solution Approach 1:
A single cage design with adjustable height can replace multiple fixed-height cage variants. The universal structure with movable end plates allows one product to serve multiple sizing requirements, eliminating the need for manufacturers to produce and inventory multiple size variations.
Solution Approach 2:
Instead of manufacturing different cage models with fixed parameters, the invention allows continuous parameter change (height adjustment) within a single cage design. This transforms the approach from discrete size variants to a continuous adjustment system, simplifying manufacturing and inventory.
4Ease of operation
If the cage is inserted in a lowest state, then insertion is facilitated, but fixation stability may be compromised
Solution Approach 1:
The cage transitions from a static low-height insertion state to a dynamically adjustable post-insertion state. The movable end plates allow the cage to be expanded to the optimal height for fixation stability after being inserted in a compact lowest state, resolving the contradiction between insertion ease and fixation reliability.
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
This design enables the cage to be optimally sized for each patient, reducing the need for multiple product variations, simplifying surgical procedures, and improving fixation stability.
Implementation Method 1
an adjustment member rotatably fixed to the proximal movable block and screwed to the distal movable block to adjust a distance between the distal movable block and the proximal movable block
Data Source
AI summary
The present disclosure relates to an intervertebral fusion cage configured to be inserted between vertebral bodies in a lowest state and improving fixation by bone screws inserted through end plates. The intervertebral fusion cage of the present disclosure may replace intervertebral fusion cages having heights within a given range. Therefore, manufacturers may reduce the number of product groups and the amount of inventory. In addition, because the height of the intervertebral fusion cage of the present disclosure is linearly adjustable according to the distance between vertebral bodies of patients unlike conventional intervertebral fusion cages having heights preset at predetermined intervals, surgery may be performed at an optimal height according to the conditions of patients.