Universal Length Bone Screw With Cuttable Shaft
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current surgical procedures require a large inventory of bone screws in various lengths and sizes, increasing costs and logistical challenges, as existing solutions do not efficiently allow for adjustment of screw length during or before the procedure.
Innovation Solution
A universal length surgical bone screw design with a shaft featuring alternating threaded and unthreaded portions and cutting flutes, allowing for adjustable length by cutting at unthreaded sections, paired with a cutting tool that can pivot to shear the screw to the desired length.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a large inventory of bone screws in various lengths and sizes is maintained, then the surgeon can have the appropriate screw length available for the procedure, but the costs and logistical challenges increase significantly
Solution Approach 1:
The patent applies universality by designing a single bone screw that can serve multiple length requirements. The screw includes a shaft with both threaded and unthreaded portions, allowing it to be cut to various lengths while maintaining functional integrity. This universal design eliminates the need for multiple screw variants, enabling one screw type to fulfill the role of what would traditionally require an inventory of different-length screws.
Solution Approach 2:
The patent applies dynamics by making the screw length adjustable rather than fixed. The inclusion of unthreaded portions in the shaft allows the screw to be dynamically modified during surgery through cutting. This dynamic adaptability enables the surgical team to adjust the screw length in real-time based on the specific anatomical requirements, transforming a static product into a dynamically configurable solution.
2Strength
If bone screws are designed with continuous threading, then the screw provides maximum structural integrity, but the screw cannot be easily cut to adjust length
Solution Approach 1:
The patent applies segmentation by dividing the screw shaft into distinct threaded and unthreaded portions. The threaded sections provide structural integrity and bone engagement, while the unthreaded sections serve as designated cutting zones. This segmentation allows the screw to maintain strength where needed (threaded portions) while providing vulnerable zones specifically designed for cutting (unthreaded portions), thus resolving the contradiction between integrity and ease of modification.
3Manufacturing precision
If multiple screw lengths are manufactured and stocked, then precise length requirements can be met, but manufacturing and inventory costs increase
Solution Approach 1:
The patent applies preliminary action by pre-configuring the screw with specific unthreaded portions at predetermined locations along the shaft. These pre-designed cutting zones are positioned to enable common length adjustments without requiring complex manufacturing processes. The unthreaded sections are strategically placed to allow cutting at standard intervals, enabling precise length matching through simple post-manufacturing cutting rather than requiring multiple precision-manufactured variants.
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
Enables surgeons to adjust bone screw length as needed during procedures, reducing inventory requirements and costs by allowing for precise length adjustments using a single initial length screw, thereby enhancing surgical efficiency and reducing waste.
Implementation Method 1
the cutting blade is positioned on the arm such that upon pivoting the first and second arms towards each other the cutting surface contacts the shaft of the bone screw to shear the bone screw shaft and to cut the bone screw to the cut length
Data Source
AI summary
An adjustable length bone screw is provided that has a shaft that can be cut at any of several predetermined positions. The adjustable length bone screws can be provided in a kit containing many bone screws having the same or different initial lengths, and these screws can be cut to the desired length for use in the surgical procedure prior to, or during, the surgical procedure. The adjustable length bone screws have a plurality of threaded shaft sections that are separated by a plurality of unthreaded shaft sections along the length of the shaft. The threaded sections have preferably at least two cutting flutes extending longitudinally along the shaft. The invention provides the adjustable length bone screws, a tool for cutting the bone screws to a desired length, kits containing the bone screws and optionally the cutting tool, and methods for using the screws and/or the cutting tool in preparation for or during a surgical procedure.