Guided Orthopedic Reamer with Cutting Struts
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current surgical tools obstruct the view of the bone lobe during cutting and lack precise control, risking damage to the bulbous bone joint during procedures for hip replacement or resurfacing, necessitating a system for controlled cutting and reshaping to accommodate a prosthetic cap.
Innovation Solution
A guided orthopedic reamer system with a cannulated reamer handle and tool, featuring coaxial cannulas for alignment with a drill guide pin, and cutting teeth designed for multiple angles and surfaces to reduce torque and prevent over-cutting, allowing precise reshaping of the bulbous bone joint.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a traditional cutting tool is used, then the cutting action can be performed, but the tool obstructs the view of the bone lobe during cutting
Solution Approach 1:
The cutting tool is divided into multiple cutting struts that are radially spaced around a central axis. This segmentation allows the cutting action to be distributed across multiple points while maintaining a compact central guide structure, improving visibility without sacrificing cutting capability
Solution Approach 2:
A central guide structure serves as an intermediary element that provides alignment and guidance for the cutting struts. This guide structure is positioned centrally to minimize obstruction while ensuring precise cutting path control
2Productivity
If aggressive cutting is used to reshape the bone joint, then the reshaping can be completed faster, but the risk of damaging the bulbous bone joint increases
Solution Approach 1:
The cutting action is segmented across multiple cutting struts that engage the bone simultaneously at different radial positions. This distributes the cutting load and allows for more controlled material removal, reducing the risk of localized damage while maintaining efficient overall reshaping
Solution Approach 2:
The cutting struts are designed to engage the bone progressively, allowing controlled material removal. The ability to adjust the extent of engagement enables precise control over the cutting depth and intensity, preventing over-cutting while maintaining surgical efficiency
3Manufacturing precision
If a simple cutting tool is used, then the device complexity is reduced, but the control and guidance precision during cutting is insufficient
Solution Approach 1:
The guidance function and cutting function are merged into a single integrated tool structure. The central guide structure and cutting struts form one unified component that provides both alignment and cutting capabilities, reducing the need for separate guidance devices while maintaining precision
Solution Approach 2:
The cutting tool is designed with multi-functionality, where the central guide structure serves both as an alignment reference and as part of the cutting mechanism. This universal design provides precise control without requiring multiple separate devices, balancing complexity and precision
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
The system reduces surgical time, increases precision, and minimizes the risk of damaging the bone joint by enabling controlled cutting and reshaping, facilitating accurate fitting of a prosthetic cap.
Implementation Method 1
The inner surfaces of the cannulas provide bearing surfaces against which the guide pin is rotatably receivable
Implementation Method 2
cutting teeth designed for multiple angles and surfaces to reduce torque and prevent over-cutting, allowing precise reshaping of the bulbous bone joint
Data Source
AI summary
Disclosed is a guided orthopedic bone reamer (10a) for cutting a profile relief shape (21a) into a joint bone (20). The reamer (10a) has a cutting head (30a) and an axial guide assembly (70). The cutting head (30a) has a profile cutting form (24a) with a rim (34) and an apex (38a). The apex (38a) connects to the cutting form (24a) by a set of struts (94). An axial guide assembly (70) has one end (44a) fixed to the apex (38a) and at the other end has a bayonet mechanism (76) connectable to a drive handle. Rim cutting teeth (36a) are set into the rim (34) to cut a cylindrical profile (21a), and bevel cutting teeth (96) integral to the struts (94) cut a bevel (25) onto the cylindrical form (21a) cut into the bone (20). A guide pin bore (12a) passes through the apex (38a) and the guide assembly (70) concentric with the axis of rotation (18) to receive a guide pin (14) to guide the reamer (10a) in cutting alignment relative to the joint bone (20) to be cut.