Dynamic Fixation Implant With Grooved Breakaway for Joint Motion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for syndesmotic injury fixation, such as rigid screw-based and tethered constraints, fail to allow physiological motion and compromise structural integrity, respectively.
Innovation Solution
A dynamic fixation implant with a breakaway portion designed to fracture at specific grooves, allowing for temporary rigid fixation followed by semi-constrained motion, utilizing a flexible constraint member to mimic ligament function.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If rigid screw-based fixation is used, then stability and simplicity of implantation are improved, but physiological motion is completely restricted and unpredictable screw failure can damage bone
Solution Approach 1:
The implant transitions from a static rigid screw to a dynamic system with a breakaway portion that allows controlled motion. The breakaway portion enables the implant to adapt between rigid fixation (when intact) and semi-constrained motion (after fracture), mimicking physiological ligament behavior while maintaining initial stability.
Solution Approach 2:
The implant is divided into distinct segments including a head portion, breakaway portion with circumferential grooves, and anchor portion. This segmentation allows the breakaway portion to fracture at predetermined locations, transforming the single rigid structure into a multi-stage system that provides both initial rigidity and subsequent motion.
2Adaptability or versatility
If tethered constraints spanning the entire ankle width are used, then physiological motion is allowed, but structural strength decreases due to unfilled drilling holes
Solution Approach 1:
The implant concentrates structural strength at critical locations through external and internal circumferential grooves in the breakaway portion. These grooves create stress concentration zones that control fracture propagation while maintaining overall implant strength, allowing motion without compromising structural integrity at the fracture site.
3Ease of manufacture
If rigid fixation is used, then ease of implantation is improved, but patient range of motion is limited and bone damage risk increases
Solution Approach 1:
The breakaway portion is pre-configured with external and internal circumferential grooves that predetermined the fracture locations. This preliminary design ensures that when fracture occurs, it happens at controlled locations away from bone surfaces, preventing bone damage while maintaining ease of initial implantation similar to rigid screws.
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
Enables physiological motion post-healing while maintaining structural integrity, reducing the risk of bone damage and patient discomfort.
Implementation Method 1
the breakaway portion is configured to concentrate stress thereat such that the implant fractures at the breakaway portion
Data Source
AI summary
Implants and related methods for achieving dynamic fixation are disclosed. The implant comprises a head portion at a proximal end of the implant comprising external threads and a first axial through hole, and an anchor portion extending from the head portion at a distal end of the implant comprising external threads and a second axial through hole in communication with the first axial through hole. The implant further comprises a flexible constraint member extending within the first and second axial through holes comprising a first end portion coupled to the head portion and a second end portion coupled to the anchor portion. At least one of the head portion and the anchor portions forms a breakaway portion with aligned internal and external circumferential grooves configured to concentrate stress thereat such that the breakaway portion fractures via forces acting on the implant to separate the head and anchor portions.