Tangential Screw Aperture Bone Plate for Humerus Fixation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current bone plate fixation devices for fractured humerus often result in bone screws being inserted at a perpendicular angle to the articular surface of the humeral head, leading to insufficient mechanical strength and a high incidence of screw penetration through the articular surface, causing loss of fracture reduction and fixation.
Innovation Solution
A bone plate design with strategically oriented screw apertures that align bone screws tangentially to the articular surface, preventing penetration and enhancing mechanical strength by distributing forces effectively across the humeral shaft and tuberosities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If bone screws are inserted at a perpendicular angle to the articular surface to maximize mechanical strength, then the mechanical strength of the connection is improved, but the bone screws penetrate through the articular surface causing loss of fracture fixation
Solution Approach 1:
The patent changes the insertion angle parameter of bone screws from perpendicular to the articular surface to a more tangential angle. The bone plate is designed with specific aperture orientations that guide screws at angles less perpendicular to the articular surface, preventing penetration while maintaining adequate mechanical strength through optimized angular geometry.
Solution Approach 2:
The patent introduces angular orientation as a critical dimension for screw insertion. By designing the bone plate with apertures oriented at specific angles relative to the articular surface, the solution adds angular control as a new dimension to prevent screw penetration while maintaining fixation strength.
2Stability of the object's composition
If long bone screws are used to maximize purchase and stability, then the stability of the connection is improved, but the tips of the bone screws will penetrate the articular surface in case of collapse or subsidence
Solution Approach 1:
The patent changes the angular parameter of screw insertion to be more tangential to the articular surface. This angular modification creates a safety margin that prevents screw tips from penetrating the articular surface even when the humeral head collapses or subsides, while still maintaining connection stability.
Solution Approach 2:
The bone plate design preliminarily positions the screw trajectories at non-perpendicular angles to the articular surface, creating a preventive geometric constraint that stops screw penetration before it can occur during humeral head collapse or subsidence.
3Strength
If bone screws are inserted at a perpendicular angle to the articular surface, then the mechanical strength is maximized, but there is a significant incidence of loss of fracture reduction and fracture fixation
Solution Approach 1:
The patent modifies the insertion angle parameter from perpendicular to more tangential relative to the articular surface. This angular change prevents screw penetration that would cause loss of fracture fixation, while the bone plate design maintains mechanical strength through optimized aperture orientations and structural geometry.
Data Source
AI summary
A fixation device serves in facilitating reduction and repair of a fractured humerus. The fixation device includes a bone plate adapted to overlie and contact portions of a proximal humerus and a humeral shaft. The bone plate includes at least a body portion overlying the humeral shaft, and an end portion overlying a portion of the proximal humerus. The end portion can facilitate attachment of the bone plate to the lesser tuberosity of the proximal humerus.