Tulip Head Collet for Poly Axial Screw
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Poly axial screw systems for spinal fusion surgery lack rigidity and stability, are difficult to assemble, and require excessive torque for adjustments, leading to inconsistent results and increased tissue damage and healing times.
Innovation Solution
A tulip connector system with a head and collet that rotatably and pivotably locks onto the ball head of a poly axial screw shaft, allowing for manual adjustment and fixation without the need for excessive torque, using a tulip assembly tool or set screw, with a design that includes a two-chamber tulip head and collet for secure locking and adjustable positioning.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If poly axial screw systems use traditional connectors with threaded nuts, then they allow adjustability, but they require excessive torque and anti-torque devices, leading to inconsistent results and increased complexity
Solution Approach 1:
The connector is divided into two separate components: a tulip head that attaches to the screw shaft and a rod that connects to the fusion rod. This segmentation eliminates the need for threaded nuts and anti-torque devices, simplifying the overall system while maintaining adjustability through the ball-and-socket joint design.
Solution Approach 2:
Instead of using a threaded nut that requires torque application to secure the rod, the invention inverts the approach by using a tulip head with a ball joint that allows the rod to be inserted and secured without torque. The adjustability is achieved through the ball joint mechanism rather than threaded fastening.
2Ease of manufacture
If poly axial screw systems use traditional connectors, then they can be assembled, but they lack rigidity and stability, making it difficult to achieve and maintain accurate angular placement
Solution Approach 1:
The tulip head incorporates a ball joint with a spherical interface that provides both mobility for angular adjustment and stability when positioned. The curved spherical surface allows rotation and pivoting while maintaining secure engagement, achieving both ease of assembly and structural stability.
3Strength
If poly axial screw systems use bulky connectors, then they may provide structural support, but they interfere with surgery, require larger incisions, and complicate imaging techniques
Solution Approach 1:
The tulip head and rod connector use a streamlined, compact design with smooth contours that minimize bulk while maintaining structural strength. The thin-walled construction provides sufficient support without requiring larger incisions or causing excessive soft tissue removal, reducing tissue damage and improving surgical access.
Data Source
AI summary
The present invention generally relates to connectors that connect bone screws with fusion rods for use in stabilizing surgery such as spinal fusion surgery, and to bone screw systems comprising such connectors. In particular, the present invention relates to poly axial screw systems configured to provide a stable but adjustable angular placement. Furthermore, embodiments of the present invention relate to tulip connectors which have a head and a collet, that are configured to rotatably and pivotably lock onto the ball head of a poly axial screw shaft into a manually adjustable locked position, to methods achieving this locked position with or without using a tulip assembly tool, and to the tulip assembly tool that has outer hooks to grab the tulip head and a center dowel to push the collet down into the locked position.