Constant-Force Self-Actuating Growing Rods for Natural Growth
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing medical implant systems for skeletal deformities require repetitive surgical interventions to adjust for natural growth, are invasive, and may suffer from fluid leakage leading to loss of distraction force.
Innovation Solution
A constant distraction force driven self-actuating growing rod system using a combination of static, intermediate, and growth rod components, compression springs, magnetic field-based spring actuation, and dynamic sealing to maintain active distraction force during natural growth without invasive procedures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If manual correction and affixation of medical implants is performed, then the corrected bony anatomy is supported, but repetitive surgical interventions are required every time the patient undergoes natural growth
Solution Approach 1:
The implant system incorporates a telescopic rod mechanism that allows automatic adjustment during natural growth. The growth rod component can telescope out of the intermediate rod component in response to growth stimuli, enabling the system to adapt dynamically to the patient's growth without requiring repetitive surgical interventions.
Solution Approach 2:
The system employs a self-actuating mechanism where the compression spring automatically expands when the growth rod telescopes, maintaining the distraction force without requiring manual intervention. This self-service capability eliminates the need for repetitive surgical adjustments while maintaining reliable support.
2Adaptability or versatility
If fluid-based systems are used to provide distraction force, then natural growth is supported, but fluid leakage occurs leading to loss of distraction force
Solution Approach 1:
The patent removes the fluid-based system entirely and replaces it with a solid mechanical compression spring system. This extraction of the problematic fluid component eliminates the risk of fluid leakage while maintaining the ability to provide and maintain distraction force during natural growth.
Solution Approach 2:
The system replaces the fluid-based distraction mechanism with a purely mechanical compression spring system. The compression spring provides the distraction force through elastic deformation, eliminating the need for fluids and associated leakage issues while maintaining adaptability to natural growth.
3Reliability
If seals are added to prevent fluid leakage, then fluid-based systems become more reliable, but the overall weight and cost of the system increases
Solution Approach 1:
By removing the fluid-based system entirely, the patent eliminates the need for seals and associated leakage prevention components. This extraction directly reduces the system's weight and complexity while maintaining reliability through the inherent mechanical properties of the compression spring system.
4Ease of operation
If the surgeon decides how much the system is to be distracted, then manual control is achieved, but human error occurs and the system is not natural growth driven
Solution Approach 1:
The system employs a self-actuating mechanism where the compression spring automatically adjusts the distraction force in response to the growth rod's telescoping motion. This self-service capability eliminates human error and ensures that the distraction force is precisely matched to the patient's natural growth, while maintaining ease of operation through automatic adjustment.
Solution Approach 2:
The system incorporates a feedback mechanism where the telescoping of the growth rod component automatically triggers the compression spring to expand and provide the appropriate distraction force. This closed-loop feedback ensures that the distraction force is continuously adjusted to match the patient's growth, eliminating human error while maintaining operational simplicity.
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 provides continuous support to corrected bony anatomy, eliminating the need for repetitive surgeries and maintaining distraction force through magnetic and mechanical mechanisms, ensuring safety and economy.
Implementation Method 1
a pre-compressed compression spring which applies an active distraction force onto the system
Implementation Method 2
at least one magnetic field-based spring actuation mechanism
Data Source
AI summary
A constant distraction force driven self-actuating growing rod system is provided for implantation on a corrected bony anatomy. The system includes components selected from the group consisting of at least one static rod, intermediate rod, or growth rod component; at least one compression spring component; at least one magnetic field-based spring actuation mechanism; at least one mechanical biasing mechanism, at least one casing, at least one guide rod and at least one spring actuator mechanism to apply an active distraction force; at least one magnetic field-based spring actuation mechanism and at least one dynamic sealing plug. During natural growth of the corrected bony anatomy, the growth rod component telescopes out of the intermediate rod component, creating a distraction force deficit that is corrected by causing the compression spring component to get compressed by the magnetic field-based spring actuation mechanism or the mechanical biasing mechanism, thereby maintaining an active distraction force.