Tibial Tray Wireless Antenna Isolation
Solution Overview
Problem
Current orthopaedic prostheses with integrated wireless communication devices face challenges in transmitting data effectively due to interference from conductive tissues and fluids, and existing solutions do not adequately address the need for secure, localized data transmission within the body.
Innovation Solution
The tibial tray assembly incorporates a wireless communication device positioned within the stem, utilizing the stem extension as an antenna tuned to 2450 MHz, with a polyethylene insulator and a sensor-transceiver configuration that transmits data only in response to an interrogation signal, ensuring secure and localized communication.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of information
If a wireless communication device is integrated into the prosthesis, then data transmission capability is improved, but interference from conductive tissues and fluids increases
Solution Approach 1:
The patent introduces an electrical insulator positioned between the wireless communication device and the conductive stem extension. This intermediary component blocks the harmful electromagnetic interference that would otherwise be conducted through the metallic stem into surrounding tissues and fluids, while still allowing the wireless device to function for data transmission.
Solution Approach 2:
The patent extracts the wireless communication device from direct contact with conductive materials by positioning it within an insulating structure. The device is taken out of the conductive environment created by the metallic stem, isolating it from harmful electrical interference while maintaining its data transmission function.
2Productivity
If the stem extension is used as an antenna, then wireless communication efficiency is improved, but the risk of interference with conductive tissues increases
Solution Approach 1:
The patent segments the stem structure into distinct functional zones: a conductive stem extension for antenna function and an insulating section for electromagnetic isolation. This segmentation allows the antenna to efficiently transmit wireless signals while the insulator prevents harmful interference from propagating into surrounding conductive tissues.
Solution Approach 2:
The patent applies different material properties to different parts of the stem structure. The stem extension maintains high electrical conductivity for effective antenna operation, while the insulator provides electrical isolation in the specific region where the wireless communication device is positioned, creating localized electromagnetic control.
3Loss of information
If the wireless communication device is positioned in the stem, then data transmission is achieved, but secure localized transmission is compromised
Solution Approach 1:
The electrical insulator acts as a mediator that confines electromagnetic fields to a localized region around the wireless communication device. By blocking electromagnetic propagation through the conductive stem, the insulator ensures that data transmission remains secure and localized, preventing signals from traveling unwanted distances through the body.
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
This configuration enables secure, localized data transmission with a restricted range, minimizing interference from conductive tissues and fluids, while maintaining the stability and integrity of the prosthetic implant.
Implementation Method 1
an electrical insulator positioned between the wireless communication device and the stem extension
Implementation Method 2
utilizing the stem extension as an antenna tuned to 2450 MHz
Data Source
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AI summary
An orthopaedic prosthesis comprising a tibial tray (12) having a platform (14) extending downwardly from a bottom surface (18) of the platform, a spacer (38) which can be coupled to an end of the stem of the tibial tray, the spacer being formed from an electrically insulating material, a stem extension (36) which can be coupled to the spacer, and a wireless communication device (70) electrically coupled to the stem extension via an antenna wire (66) and configured to transmit data using the stem extension as an antenna.