Double Epiphysiodesis Plate Fixation for Uniform Bone Growth Inhibition
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current fixation devices for treating axial deformities in limbs, such as valgus and varus knees, fail to adequately block bone growth in a central portion of the bone, leading to incomplete correction of deformities due to uneven growth inhibition and potential further deformation.
Innovation Solution
A double epiphysiodesis plate system with a rigid link, comprising two plates positioned on opposite sides of the bone and connected by a rod that crosses the bone portion, effectively stopping bone growth in the central area by using tie-rods and various fixation mechanisms to secure the plates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single plate is used for epiphysiodesis, then the device complexity is low, but the bone growth inhibition is incomplete and non-uniform
Solution Approach 1:
The single plate is divided into two separate plates positioned on opposite sides of the bone. Each plate independently inhibits bone growth from its respective side, achieving uniform and complete growth inhibition across the entire epiphyseal plate while maintaining manageable device complexity through modular design
Solution Approach 2:
Different regions of the bone (opposite sides of the epiphyseal plate) are treated with separate plates to provide localized growth inhibition. This ensures that each region receives appropriate mechanical constraint, resulting in uniform overall inhibition without the complexity of a single complex plate design
2Reliability
If screws are used to fix the plate, then the fixation strength is sufficient, but the bone growth is not completely blocked due to interference with cartilage
Solution Approach 1:
The fixation system is segmented into two plates with screws positioned on opposite sides of the bone. This distribution allows screws to be placed in optimal positions that avoid cartilage interference zones while maintaining effective growth inhibition, as each plate-screw assembly works independently to block growth from its side
Solution Approach 2:
The rod connecting the two plates serves as an intermediary element that provides additional fixation stability without directly interfering with the cartilage. It transmits mechanical constraints between the two plates, enhancing overall fixation strength while preserving cartilage function
3Reliability
If a double plate system with rod is used, then the bone growth inhibition is uniform and complete, but the device complexity increases
Solution Approach 1:
The device is segmented into two independent but coordinated plates connected by a rod. This segmentation allows each component to be optimized for its specific function while working together to achieve uniform growth inhibition, with the rod providing structural coordination without requiring a single complex integrated design
Solution Approach 2:
Two separate plate systems are merged through the connecting rod to form a coordinated fixation device. This merging achieves uniform and complete growth inhibition by combining the effects of both plates, while the modular nature of the components keeps the overall device complexity manageable through standardized interfaces
Data Source
AI summary
The invention concerns an inner fixation device for the correction of axial deformities of a limb, for example a long limb, of the type comprising at least one plate (2, 2′) for epiphysiodesis with at least a pair of lobes (3,4) each provided with a through hole (7) to be laterally fixed to a bone portion or to a long bone head. Advantageously, the device (1) comprises one second plate (12, 12′) placed on the opposite side of the bone portion with respect to said at least one plate (2, 2′) and connected to that by at least one rod (15) passing through the bone portion. The rod (15) is extended through the bone in parallel to an epiphyseal plate and it has opposite extremities (16,17) connected to the plates (2,2′; 2,12′) to keep them close to the bone and to stop the bone growth in one central portion of the bone.