Dynamic Compression Fixation Devices for Bone Healing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current bone fracture treatments often result in improper healing, including delayed union, malunion, and nonunion, due to inadequate compression and stabilization of broken bones, leading to loss of function, chronic pain, and increased medical costs.
Innovation Solution
Development of implantable devices with a dynamic compression portion that can transform between compact and elongated configurations, utilizing materials like Nitinol, to provide controllable and continuous compression to the bone segments, enhancing bone healing and stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional static compression devices are used to stabilize broken bones, then bone alignment is maintained, but improper healing occurs due to inadequate compression and lack of micro-motion accommodation
Solution Approach 1:
The patent applies the dynamics principle by incorporating a shape memory alloy (SMA) element that can dynamically change its mechanical properties between a first state (higher stiffness, lower compression) and a second state (lower stiffness, higher compression). This allows the device to adapt to different stages of bone healing, providing micro-motion accommodation initially and then transitioning to stable compression, thereby improving bone healing success rate without requiring multiple separate devices.
Solution Approach 2:
The patent utilizes parameter changes by employing a shape memory alloy element whose stiffness and compression characteristics can be changed between two distinct states. The SMA element's phase transformation between austenite and martensite phases enables controlled modification of mechanical parameters, allowing the device to provide appropriate compression levels at different healing stages, thus resolving the contradiction between reliable healing and device simplicity.
2Productivity
If continuous compression is applied to bone segments to promote healing, then healing rate improves, but bone misalignment occurs due to lack of micro-motion accommodation
Solution Approach 1:
The device employs a shape memory alloy element that can transition between a first state with higher stiffness (allowing micro-motion) and a second state with lower stiffness (providing continuous compression). This dynamic adaptation enables the device to accommodate micro-motion during early healing stages to maintain alignment, then transition to continuous compression to accelerate healing, thus resolving the contradiction between healing rate and alignment stability.
Solution Approach 2:
The patent implements continuity of useful action through the SMA element that can maintain compression force continuously while adapting its stiffness characteristics. The shape memory effect allows the element to continuously apply compressive force to bone segments while adjusting its mechanical properties to accommodate micro-motion needs, ensuring both alignment stability and sustained healing promotion throughout the recovery process.
3Strength
If rigid fixation devices are used to stabilize fractures, then immediate stability is achieved, but fatigue failure occurs due to inability to accommodate bone micro-motion
Solution Approach 1:
The patent applies dynamics by using a shape memory alloy element that can change its stiffness between a first state (higher stiffness for immediate stability) and a second state (lower stiffness for micro-motion accommodation). This dynamic property allows the device to provide rigid fixation initially for stability, then adapt to accommodate physiological micro-motion during healing, thereby improving fatigue resistance without sacrificing initial fixation strength.
Solution Approach 2:
The device utilizes composite materials by combining a shape memory alloy element with other structural components. The SMA element's unique properties of superelasticity and phase transformation enable the composite structure to exhibit both high strength for immediate stability and enhanced fatigue resistance through controlled flexibility, resolving the contradiction between fixation strength and fatigue reliability.
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 implantable devices offer improved bone healing rates, fatigue failure resistance, and micro-motion accommodation, reducing the risk of improper healing and associated complications by matching the elastic properties of bone and providing sustained compression over time.
Implementation Method 1
the dynamic compression portion comprises a material configured to transform between the first, compact configuration and the second elongated configuration
Implementation Method 2
providing controllable and continuous compression to the bone segments, enhancing bone healing and stability
Data Source
AI summary
Devices and methods are disclosed for orthopedic uses, such as treating and compressing a broken bone. An implantable device may be provided with an elongate body, a head region, a bone engagement part such as an anchor region or threads, and a dynamic compression portion in either a first axially compact configuration or a second axially elongated configuration and configured to transform between the first axially compact configuration and the second axially elongated configuration.