Partially Insulated Bone Screw for Targeted Electrical Stimulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for stimulating bone growth and tissue healing, such as using wire electrodes, are prone to failure, imprecise placement, and can cause adverse effects due to unneeded current distribution, while conventional screws do not facilitate electrical stimulation effectively.
Innovation Solution
A partially insulated screw with an electrically conducting and insulating portion is used to direct electrical current specifically to the bone, allowing for precise stimulation and minimizing unwanted current flow through the use of a dual-electrode system connected to an electrical power source.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If wire electrodes are used to stimulate bone growth, then bone growth stimulation is achieved, but the electrodes are susceptible to failure and require additional surgery for repair
Solution Approach 1:
The patent combines the electrode function with the bone screw function into a single integrated device. The screw itself serves as the electrode, eliminating the need for separate wire electrodes that are prone to failure. This merging of functions resolves the reliability issue by using a robust screw structure that is both mechanically stable and electrically conductive.
Solution Approach 2:
The screw-electrode is designed to be self-contained and self-supported within the bone structure. Once implanted, it provides both mechanical fixation and electrical stimulation without requiring external wiring or additional components that could fail. The screw serves its own purpose as both structural support and stimulation delivery mechanism.
2Duration of action of moving object
If wire electrodes are used for bone growth stimulation, then current can be applied for extended periods, but current passes through areas where it is unneeded and could have adverse effects
Solution Approach 1:
The screw electrode design enables localized current delivery to specific bone regions. By positioning the screw at the precise location requiring stimulation and using its threaded structure embedded in the bone, the current is confined to the local area around the screw rather than dispersing through surrounding tissues. This resolves the issue of unwanted current distribution while maintaining extended duration application.
Solution Approach 2:
The bone itself acts as an intermediary that guides and confines the electrical current. The screw delivers current to the bone, and the bone's conductive properties channel the current through the specific bone region needing stimulation, preventing current from reaching areas where it could cause adverse effects.
3Stability of the object's composition
If conventional screws are used to immobilize bones, then bone movement is limited, but they do not facilitate electrical stimulation and may conduct current to unwanted areas
Solution Approach 1:
The screw is designed to perform multiple functions simultaneously: it provides mechanical immobilization of the bone (stability function) and serves as an electrical electrode for bone growth stimulation (electrical function). This multi-functionality resolves the contradiction by making the same device both a structural fastener and an active stimulation source, eliminating the need for separate conventional screws.
Solution Approach 2:
The screw can be constructed from composite materials or coated with materials that provide both mechanical strength for immobilization and electrical conductivity for stimulation. This composite approach allows the screw to simultaneously achieve structural stability and electrical functionality, resolving the limitation of conventional单一-material screws.
4Ease of operation
If imprecise electrode placement is used, then placement procedure is simpler, but more energy is required and current reaches areas where it is unneeded
Solution Approach 1:
The patent replaces the complex mechanical system of wire electrode insertion and positioning with a simpler screw-driven system. The screw can be precisely positioned using standard orthopedic drilling and tapping techniques, and its threaded structure automatically secures it in place. This mechanical substitution simplifies the placement procedure while enabling precise positioning, reducing the energy required compared to imprecise wire electrode placement.
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 approach enhances bone growth, tissue healing, and pain control by providing a targeted electrical field, reducing the need for additional surgery and minimizing adverse effects, while improving recovery and pain management in spinal cord and nerve injuries.
Implementation Method 1
an electrical conductor electrically connectable to the shaft for conveying current through the shaft to the bone through the conducting portion of the shaft
Implementation Method 2
passing an electrical current through the bone... stimulate bone growth... electrical fields have also shown significant promise in aiding healing and recovery in nerve and spinal cord injury
Data Source
AI summary
A screw for use in stimulating bone growth, tissue healing and/or pain control. The screw includes an elongate shaft having a length extending between opposite ends, an exterior surface and a screw thread formed on the exterior surface of the shaft and extending along at least a portion of the length. The shaft has an electrically conducting portion and an electrically insulating portion. The screw also includes a head adjacent one end of the shaft for engaging the screw to rotate the screw and thereby drive it into bone. The screw includes an electrical conductor electrically connectable to the shaft for conveying current through the shaft to the bone through the conducting portion of the shaft.