Swinging Spinal Screw Channel for Controlled Rod Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing spinal support rod systems face challenges in applying appropriate forces during implantation to correct spinal deformations, particularly in ensuring balanced forces across the spinal column and preventing bone tissue damage from high localized forces.
Innovation Solution
A fixation screw assembly with a rod receiving channel that can swing through a range of angles relative to the fixation screw, allowing for easier insertion and alignment of the support rod, combined with a dual locking device to secure the rod in place, enabling controlled application of translational and torsional forces.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If a fixed support rod system is used to correct spinal deformities, then the alignment can be maintained, but it is difficult to apply progressive corrective forces without risking bone tissue damage
Solution Approach 1:
The support rod system incorporates adjustable locking mechanisms that allow the rod to transition from a flexible state during implantation to a fixed state after correction. The rod can be bent to the desired configuration and then locked in place, enabling progressive force application without permanent damage to bone tissue.
Solution Approach 2:
The system allows changing the mechanical parameters of the support rod by adjusting the locking mechanisms at different positions. This enables control over the magnitude and distribution of corrective forces applied to vertebrae, preventing excessive localized forces that could damage bone tissue.
2Reliability
If multiple locking mechanisms are used to secure the rod, then the rod can be firmly fixed, but the implantation procedure becomes more complex
Solution Approach 1:
The locking mechanism is integrated directly into the support rod structure itself, combining the rod and locking components into a single unified device. This reduces the number of separate parts and simplifies the implantation procedure while maintaining reliable fixation stability.
Solution Approach 2:
The support rod incorporates self-locking features that allow it to be securely fixed without requiring multiple separate locking operations. The rod can be bent to the desired shape and then locked in place through an integrated mechanism, reducing procedural complexity.
3Ease of operation
If the support rod is made highly flexible to accommodate spinal curvature, then it can be easily inserted, but it may not provide sufficient corrective force
Solution Approach 1:
The support rod is designed with dynamic mechanical properties that allow it to be flexible during insertion but rigid during correction. The rod can be bent to match spinal curvature during implantation, then locked in place to provide sufficient corrective force for maintaining alignment.
Solution Approach 2:
The mechanical parameters of the support rod are changed from flexible to rigid through the locking mechanism. During insertion, the rod maintains flexibility for easy accommodation to spinal curvature, then after locking, it provides the necessary rigidity to deliver adequate corrective force.
Data Source
AI summary
A method of treating a spinal column shape deformation includes fixing at least two fixation screw assemblies to respective vertebrae, sliding a rod between the arm extensions on each of the fixation screw assemblies, swinging the channels of the screw assemblies relative to the fixation screws so that the channels become less inclined to the axes of the fixation screws, and so that the rod is located generally posteriorly of the spinal column, locking the channel against swinging relative to the screw, rotating the rod about its axis relative to at least one of the channels, and locking the rod against movement relative to the channel.