Spinal Rod Reducer Assembly for Deep Seating and Easy Disengagement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rod reduction instruments for spinal fixation constructs are bulky, time-consuming, and difficult to disengage from anchors, especially in limited surgical access conditions, and often fail to achieve desired reduction depth and force requirements.
Innovation Solution
A dual rod spinal fixation system with a rod reducer featuring a translation unit and coupling unit, including a drive knob and attachment arms, allows for efficient seating and disengagement of a spinal rod into a fixation anchor, utilizing a lock mechanism for secure engagement and disengagement through rotational and translational movements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If traditional rod reduction instruments are used, then rod seating can be achieved, but the instruments are bulky and difficult to disengage from anchors in limited surgical access conditions
Solution Approach 1:
The rod reduction instrument is divided into distinct functional segments: a head portion for engaging the rod, a body portion with reduced profile for navigating limited access, and a shaft portion for force transmission. This segmentation allows the instrument to maintain functionality while reducing bulk and improving disengagement capability in constrained surgical environments.
Solution Approach 2:
The instrument employs a reverse action mechanism where rotational movement of the head portion in one direction engages the rod for reduction, and rotation in the opposite direction automatically disengages the instrument from the anchor. This inverted operational sequence simplifies the disengagement process that traditionally requires complex manual manipulation.
2Productivity
If traditional rod reduction instruments are used, then rod seating can be achieved, but the process is time-consuming
Solution Approach 1:
The instrument is pre-configured with the rod engagement features and force transmission mechanisms already in place during manufacturing. The head portion includes pre-formed engagement surfaces and the shaft includes pre-set mechanical advantages, eliminating the need for time-consuming intraoperative adjustments or complex assembly steps during the reduction process.
Solution Approach 2:
The instrument incorporates dynamic mechanical advantage through its shaft portion design, allowing the applied force to be automatically amplified during the reduction process. This dynamic force multiplication reduces the time required for rod seating by eliminating the need for multiple incremental adjustments or repeated instrument applications.
3Manufacturing precision
If traditional rod reduction instruments are used, then rod seating can be achieved, but the instruments are frustrating to employ and limited in achievable reduction depth
Solution Approach 1:
The shaft portion acts as an intermediary mechanical element that transmits and amplifies the surgeon's applied force with precise mechanical advantage. This intermediary mechanism provides controlled, progressive rod reduction with achievable depth precision while maintaining ease of operation through intuitive force application and automatic force multiplication.
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
Facilitates simple and efficient rod manipulation during spinal fixation, ensuring secure seating and easy disengagement, even in constrained surgical environments, thereby improving the installation process.
Implementation Method 1
a lock mechanism comprising a drive knob
Data Source
AI summary
This disclosure describes example embodiments of rod reduction instrumentation and other rod and vertebrae manipulation instruments. The rod reducers can be used during the installation of a rod based surgical fixation system to help urge the rod into the fixation anchors. The reducers described provide various configurations delivering large reduction distance capabilities, strong controlled reduction coupled with an ability to quickly advance the reducer if desired, and reduction of bulk through the surgical corridor.