Bone Screw Removal System with Compressible Spring Lock
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bone screw retention systems for cervical spine plating systems do not adequately allow for the removal of screws, complicating surgical procedures and potentially leading to screw loosening or backout over time.
Innovation Solution
A bone screw removal system featuring a driver assembly and spring members that securely lock screws into place and allow for selective removal by compressing spring members using a tubular sleeve and tongue mechanism, enabling angular placement and secure fixation of screws.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a bone screw retention system is used to prevent screws from loosening or backing out, then screw security is improved, but the ability to remove screws when needed deteriorates
Solution Approach 1:
The retention system employs a dynamic spring-loaded mechanism where the spring member can be compressed to release the bone screw. During normal operation, the spring maintains constant pressure on the screw head to prevent backing out. When removal is needed, the surgeon applies force to compress the spring, allowing the screw to be extracted. This dynamic system resolves the contradiction by providing both secure retention during use and easy removal when needed.
Solution Approach 2:
The spring member acts as an intermediary between the bone screw and the plate system. It provides the retaining force to prevent screw loosening while also serving as the release mechanism when compression is applied. This intermediary element enables both functions - secure retention and easy removal - by mediating the interaction between the screw and the fixation system.
2Reliability
If spring members are used to lock screws into place, then screw fixation security is improved, but device complexity increases
Solution Approach 1:
The spring member is designed to be self-loading, automatically engaging the bone screw upon insertion. The screw's own insertion action compresses the spring, which then self-locks the screw in place without requiring additional fastening steps or complex mechanisms. This self-service approach provides secure fixation while minimizing 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 system ensures secure fixation and easy removal of bone screws, preventing loosening and backout, while allowing for optimal screw placement and stabilization of the cervical spine during surgical procedures.
Implementation Method 1
a spring member operable positioned within the bore such that compression of the spring member locks the bone screw securely in place
Implementation Method 2
enabling angular placement and secure fixation of screws
Data Source
AI summary
A bone screw removal system for a bone screw retaining system that includes an implant having a plate, which defines a plurality of transversely extending bores that are configured to receive a bone screw for engaging the plate to the cervical spine, and an elastically deformable spring member positioned therein a cavity of the plate such that portions of the spring member can extend into a portion of an upper region of each of the bores of a pair of opposing bores, the spring member being movable between a first relaxed, expanded position and a second, compressed position. The bone screw removal system having at least one tongue member that is configured to selectively act on the spring member of the bone screw retaining system.