Expandable Reamer Blade Deployment for Bone Resection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current surgical methods for removing diseased bone, such as in treating avascular necrosis and osteochondritis dissecans, lack efficient tools for precise and controlled bone resection, risking damage to surrounding tissue and requiring advancements for improved bone tunnel preparation and diseased bone removal.
Innovation Solution
The development of expandable reamers with a blade that can be incrementally advanced from a non-cutting to a cutting position using a selector sleeve and actuator assembly, allowing for precise socket formation in bone, reducing the risk of tissue damage and enabling controlled removal of diseased bone.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional surgical cutting devices are used to remove diseased bone, then the procedure can be performed with simple tools, but the precision and control for socket formation is insufficient, risking damage to surrounding tissue
Solution Approach 1:
The reamer is divided into distinct functional segments: an outer tube for protection and insertion, an inner shaft for actuation, and a separate blade assembly that can be deployed independently. This segmentation allows the blade to remain concealed during insertion and only be exposed when needed for cutting, thereby improving precision while managing complexity through modular design
Solution Approach 2:
The blade is designed to be dynamically deployable rather than fixed. It can be transitioned between a concealed state during insertion and a deployed cutting state during operation. This dynamic capability allows the device to adapt its function at different stages of the procedure, improving precision by ensuring the cutting edge is only exposed when precisely positioned
2Productivity
If the blade is deployed to a cutting position for removing diseased bone, then effective bone resection is achieved, but the risk of damage to surrounding tissue increases
Solution Approach 1:
The reamer is inserted into the bone tunnel with the blade in a concealed, non-cutting position before reaching the target diseased bone. This preliminary positioning ensures that the cutting edge is only exposed after precise placement, allowing the surgeon to prepare the exact location for bone removal while minimizing the risk of accidental damage to surrounding healthy tissue
Solution Approach 2:
The outer tube serves as an intermediary protective structure that conceals and protects the blade during insertion and positioning. It acts as a mediator between the cutting element and the surrounding tissue, allowing the blade to remain hidden until the reamer is precisely positioned, thereby reducing harmful effects on surrounding tissue
3Measurement precision
If the blade is advanced incrementally using the actuator assembly, then precise control over cutting depth is achieved, but the device complexity increases
Solution Approach 1:
The actuator assembly replaces manual blade advancement with a controlled mechanical system. The selector sleeve with helical groove and pin mechanism converts rotational motion into precise linear advancement of the blade. This mechanical substitution provides incremental, measurable control over blade deployment while maintaining a relatively simple overall device structure through the use of basic mechanical components
Solution Approach 2:
The actuator assembly enables precise control by changing the positional parameter of the blade in incremental steps. As the selector sleeve rotates, the pin travels along the helical groove, translating rotational movement into controlled linear displacement of the blade. This parameter change approach allows precise measurement and control of blade advancement distance
Data Source
AI summary
An expandable reamer includes, inter alia, an outer tube, an inner shaft, a movable blade, and an actuator assembly. The expandable reamers can be used to remove diseased bone.