Pedicle Screw Reducer Instruments for Rod Reduction and Setscrew Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing pedicle screw reducer instruments often lack sufficient reduction capacity, particularly in larger patients and minimally invasive surgical techniques, and face difficulties in threading setscrews due to axial misalignment, leading to potential component damage.
Innovation Solution
The use of a reducer clip that couples to a pedicle screw receiver, an inserter-reducer shaft, a reducer handle, and a driver handle to facilitate additional reduction capability and secure the rod to the pedicle screw through threaded engagement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If extended tabs with threads are added to the pedicle screw receiver member to increase reduction capacity, then the reduction capability is improved, but the device complexity increases
Solution Approach 1:
The receiver member is divided into separate functional components: the main body, extended tabs with threads, and a detachable closure mechanism. This segmentation allows the reduction function to be enhanced through the tabs while keeping the main structure relatively simple and modular.
Solution Approach 2:
The extended tabs are designed to be detachable or breakable after use, transforming from a static permanent feature to a dynamic component that can be removed once the rod is fully reduced and secured. This provides additional reduction capacity when needed while simplifying the overall structure when not needed.
2Manufacturing precision
If rigid positioning of the setscrew is used in prior instruments, then the setscrew position is fixed, but axial misalignment occurs making threading difficult and causing component damage
Solution Approach 1:
The setscrew positioning mechanism transitions from rigid fixed positioning to dynamic adjustable positioning. The setscrew can be positioned at different locations along the extended tabs, allowing the operator to align the setscrew axially with the pedicle screw receiver member before threading, thereby preventing misalignment and component damage.
Solution Approach 2:
The extended tabs serve as an intermediary element between the rod and the setscrew. They provide a threaded interface that allows controlled engagement and reduction, mediating the interaction between the fixation element and the closure mechanism to ensure proper alignment and prevent damage.
3Length of moving object
If the extended tabs are made longer to reach above tissue in larger patients, then the reduction capacity is improved, but the risk of tissue damage and surgical complexity increases
Solution Approach 1:
The extended tabs are designed as detachable components that can be removed after the rod is fully reduced. This allows the tabs to be extended to the necessary length to reach above the tissue in larger patients during the reduction process, but then removed afterward to minimize the presence of foreign material and reduce the risk of tissue damage or infection.
Solution Approach 2:
The extended tabs function as disposable or single-use components in this context. They are inserted to provide the necessary reduction capacity, perform their function during the surgical procedure, and then discarded or removed. This approach allows for sufficient tab length without long-term concerns about tissue interaction or infection.
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
Provides enhanced reduction capacity and secure threading of setscrews, reducing the risk of component damage and improving surgical efficiency.
Implementation Method 1
a reducer handle having a lumen extending from a proximal end to a distal end thereof and threads formed along an outer distal portion thereof, the reducer handle threads interfacing with the threads formed along the proximal portion of the reducer clip
Implementation Method 2
a driver handle that can rotate the inserter-reducer shaft to engage the setscrew with threads formed on the pedicle screw or extension tabs thereof
Data Source
AI summary
Surgical instruments and methods to aid in reducing or urging a spinal fixation element into a pedicle screw or other implant are disclosed. Disclosed instruments and methods facilitate delivery of a setscrew or other closure, reduction of a rod or other spinal fixation element into a pedicle screw, and securing the rod relative to the pedicle screw using the setscrew. Example instruments and methods can utilize a reducer clip that couples to a proximal end of a pedicle screw receiver head or extension tabs thereof, an inserter-reducer shaft that can couple with a setscrew at its distal end, a reducer handle that can threadably engage with the reducer clip to translate the shaft and thereby reduce a rod, and a driver handle that can rotate the inserter-reducer shaft to engage the setscrew with threads formed on the pedicle screw or extension tabs thereof.