Dynamization Strut with Internal Compression Spring
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing external fixation devices face challenges in achieving controlled destabilization for bone healing, as current methods often result in varying levels of instability and fail to effectively limit dynamization to a desired direction or axis of movement.
Innovation Solution
The development of a dynamization strut comprising a sleeve, shaft, biasing member, bushing, and holding pin, which allows for compressive movement without changing the total length of the strut, enabling adjustable dynamization through rotational mechanisms and spring constants, ensuring controlled compressive forces are applied.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional external fixation devices use removable bars or pins to achieve dynamization, then bone healing can be accelerated through controlled destabilization, but the level of instability varies widely and the direction of movement cannot be effectively limited
Solution Approach 1:
The strut incorporates a dynamic adjustment mechanism that allows the fixation device to transition from a static rigid structure to a dynamically adjustable system. The dynamization mechanism enables controlled movement along the longitudinal axis while maintaining stability in other directions, allowing the system to adapt its rigidity based on healing progression.
Solution Approach 2:
The invention changes the mechanical parameters of the fixation device by introducing adjustable compression springs and friction elements. By modifying the spring constant, friction coefficient, and pre-compression force, the system can precisely control the magnitude and direction of dynamization forces applied to the bone fracture.
2Stability of the object's composition
If the external fixation device is made rigid to maintain stability during bone healing, then alignment is preserved, but controlled destabilization needed for accelerated healing cannot be achieved
Solution Approach 1:
The invention applies partial destabilization rather than complete rigidity removal. The dynamization mechanism provides controlled micro-movements and compressive forces that are sufficient to stimulate bone healing while maintaining enough stability to preserve alignment. This partial action approach accelerates healing without compromising structural integrity.
Solution Approach 2:
The compression springs provide continuous compressive force on the bone fracture site throughout the healing process. This continuous useful action maintains optimal contact between bone fragments while allowing controlled movement, ensuring that the therapeutic effect of compression is sustained without interruption as the bone heals.
3Adaptability or versatility
If the strut allows compressive movement through internal components, then dynamization is achieved, but the total length of the strut must remain unchanged
Solution Approach 1:
The dynamization mechanism is nested within the strut's internal structure. The compression springs, friction elements, and adjustment components are contained within the hollow interior of the strut, allowing the external dimensions and total length to remain unchanged while providing sophisticated internal dynamization functionality.
Solution Approach 2:
The invention resolves the length constraint by shifting the dynamization mechanism from longitudinal extension/compression to internal compression spring action. The springs compress radially and axially within the fixed-length strut body, generating dynamization forces without changing the overall strut length, effectively moving the mechanism to a different dimensional space.
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 solution provides a controlled and adjustable dynamization mechanism that enhances bone healing by allowing precise adjustment of compressive forces, maintaining strut length and ensuring consistent stability during bone healing processes.
Implementation Method 1
a biasing member (e.g., a spring) disposed within the first section of the inner recess of the sleeve
Data Source
Figure 1~2
Figure 3A~4
Figure 5A
AI summary
Dynamization struts and methods of use are provided. A dynamization strut may comprise a sleeve, a shaft, a biasing member, and a bushing. The sleeve may comprise an inner recess with a first and second section. The shaft may comprise an interior section to be disposed within the inner recess of the sleeve. The biasing member may be disposed around the interior section of the shaft, and sized to fit within the first section of the inner recess of the sleeve. The bushing may be secured against a portion of the shaft. Rotation of the bushing may provide for compressive movement of the biasing member relative to the sleeve and shaft. Compression of the biasing member may occur without a corresponding change in a total length of the dynamization strut. Rather, changes in the length of the strut may occur as a result of external compressive forces acting upon it.