Axial Rotational Stopping Device for Threaded Implants
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current vertebral fixation procedures face challenges in controlling rotational and axial forces during the implantation of allograft bony void fillers or synthetic implants, leading to potential damage to threads and drive features, especially due to variability in bone density and strength.
Innovation Solution
An axial and rotational stopping device with a two-part mechanism featuring mating toothed surfaces that prevent clockwise rotation once a predetermined depth is reached, ensuring consistent depth control and preventing damage to threads and drive features.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a threaded shaft is used to achieve stable fixation, then fixation stability is improved, but control of rotational forces during implantation deteriorates
Solution Approach 1:
The patent introduces an intermediary depth stop mechanism with toothed surfaces that mediates between the implantation tool and the threaded shaft. This depth stop engages with the threaded shaft at a predetermined depth and prevents further rotation through the toothed engagement, thereby controlling rotational forces while maintaining fixation stability.
Solution Approach 2:
The depth stop is pre-configured with toothed surfaces that engage with the threaded shaft before complete implantation. The predetermined depth is established in advance, and the toothed engagement is designed to prevent over-rotation before the implant is fully seated, preventing damage to threads and drive features.
2Productivity
If axial force is applied during implantation, then implantation speed is improved, but damage to threads and drive features increases
Solution Approach 1:
The depth stop acts as an intermediary that limits the transmission of axial force to the threaded shaft. The axial force is controlled by the predetermined depth of the depth stop, preventing excessive force that could damage threads and drive features while still allowing sufficient force for implantation.
Solution Approach 2:
The depth stop provides beforehand cushioning by establishing a predetermined depth limit before implantation begins. The toothed surfaces are designed to engage and prevent further axial advancement before damage can occur, cushioning against excessive force application.
3Reliability
If rotation is prevented during implantation, then thread damage is reduced, but implantation complexity increases
Solution Approach 1:
The anti-rotation mechanism is segmented into separate toothed surfaces on the depth stop and corresponding surfaces on the threaded shaft. This segmentation allows the anti-rotation function to be integrated into the existing implantation tool without requiring a completely new complex mechanism.
Solution Approach 2:
The depth stop combines multiple functions into a single component: it provides axial depth control, rotational prevention through toothed engagement, and structural support. By merging these functions, the overall device complexity is reduced while maintaining thread integrity.
Data Source
AI summary
Disclosed is an axial and rotational stopping device for use when creating threads in a predrilled pilot hole or inserting an allograft bony void filler or synthetic implant into a threaded hole. The device can also provide consistent depth control for drilling a pilot hole, tapping the hole to create threads, and implanting an allograft bony void filler or synthetic implant while preventing damage to the threads in the tapped hole that would be caused by continuing to rotate a tap once the depth stop has been reached and the tap can no longer advance in the axial direction, as well as preventing damage to the threads in the tapped hole, the threads on the mating allograft bony void filler or synthetic implant, and the drive features on either the driver instrument or the allograft bony void filler or synthetic implant.