Bone Plate Locking Cannula Alignment Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bone plate attachment systems face misalignment issues due to the removal of drill guides before inserting bone screws, leading to potential misplacement or misalignment of the bone plate relative to the bone.
Innovation Solution
A bone plate locking cannula and drill guide assembly, where locking cannulas are temporarily attached to the bone plate, allowing bone screws to be inserted through the cannula without removing it, ensuring proper alignment and secure attachment of the bone plate to the bone.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the drill guide is removed from the bone plate before inserting the bone screw, then the bone screw can be inserted through the aperture, but the bone plate may move relative to the bone causing misalignment
Solution Approach 1:
The locking cannula serves as an intermediary device that bridges the drill guide and the bone plate. It maintains the precise alignment between the pilot hole and screw aperture while allowing the bone screw to be inserted. The cannula acts as a temporary holder that prevents bone plate movement during the critical insertion phase, resolving the contradiction between ease of operation and alignment precision.
Solution Approach 2:
The locking cannula is pre-attached to the bone plate before the bone screw insertion procedure. This preliminary attachment ensures that the alignment between the pilot hole and screw aperture is maintained throughout the entire surgical process, preventing any potential misalignment that would occur if the drill guide were removed.
2Manufacturing precision
If the drill guide is temporarily attached to the bone plate, then proper alignment of the pilot hole is ensured, but the bone plate may move relative to the bone after drill guide removal
Solution Approach 1:
The locking cannula functions as a stable intermediary that maintains both the alignment precision of the pilot hole and the stability of the bone plate position. It provides a rigid connection between the drill guide aperture and the bone plate, preventing any movement during the critical period when the bone screw is being inserted.
Solution Approach 2:
By pre-attaching the locking cannula to the bone plate before the surgical procedure, the system ensures that both alignment precision and stability are established in advance. The cannula remains in place throughout the procedure, providing continuous support and preventing any potential displacement of the bone plate.
3Ease of operation
If the internal diameter of the locking cannula is made large enough to allow bone screw passage, then the bone screw can be inserted through the cannula, but the cannula may interfere with the screw receiving aperture configuration
Solution Approach 1:
The locking cannula is designed with non-uniform internal diameter characteristics. The proximal portion has a larger internal diameter to facilitate easy bone screw insertion, while the distal portion maintains a smaller diameter that is compatible with the screw receiving aperture configuration. This local differentiation resolves the contradiction between ease of operation and device complexity.
Solution Approach 2:
The locking cannula is segmented into different portions with different internal diameter characteristics. The proximal segment provides a large bore for screw insertion, while the distal segment maintains compatibility with the bone plate aperture. This segmentation allows the single cannula component to satisfy multiple requirements without increasing overall system complexity.
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 solution prevents misalignment and secure attachment of the bone plate to the bone by allowing bone screws to be inserted without removing the locking cannula, maintaining the alignment of pilot holes and screws, thus enhancing the stability and accuracy of the bone plate fixation.
Implementation Method 1
the cannula being sized to receive a tubular drill guide... the locking cannula and bone plate being structured such that the cannula is temporarily mountable to the bone plate utilizing a threaded connection
Implementation Method 2
a pilot hole is created in the bone, the bit is removed from the drill guide
Implementation Method 3
the bone screw is inserted through the screw receiving aperture and into the pilot hole to secure the bone plate to the bone
Data Source
AI summary
A bone plate locking cannula and drill guide assembly having a locking cannula detachably mountable onto screw-receiving apertures of a bone plate and a drill guide received within the locking cannula such that pilot holes are drilled through the apertures into bone at the proper angle to receive bone screws. The screw receiving apertures have a proximal bore of greater diameter than a distal bore, and the proximal bore is provided with internal threading to mate with external threading located on the distal end of the locking cannula. The bone screws are inserted through the locking cannula after removal of the drill guide and fastened into the bone to secure the bone plate in position without having to remove the locking cannulas from the bone plate, the internal diameter of the locking cannula bore being greater than the maximum diameter of the screw heads. The locking cannula is detached from the bone plate after the bone plate has been secured in place on the bone.