Pars Clamp with Movable Claws for Spinal Rod Fixation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Securing spinal rods to vertebrae that are too small, fragile, or damaged poses challenges, and the use of bone screws requires significant time and hardware during surgical procedures, complicating spinal fixation.
Innovation Solution
A modular clamp device with adjustable claws and rod clamps that can grip vertebrae without the need for bone screws, featuring movable and immovable claws, elongate tabs, and a bar system for securing spinal rods, allowing for customizable fit and reduced surgical complexity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If bone screws are used to secure spinal rods to vertebrae, then reliable fixation is achieved, but surgical time and hardware complexity increase significantly
Solution Approach 1:
The clamp device is divided into multiple independent claws (typically three) that can be positioned and adjusted separately on the vertebra. Each claw can be independently secured, allowing for modular assembly and reduced surgical complexity compared to traditional bone screw systems that require precise drilling and fastening of multiple components.
Solution Approach 2:
The clamp device is designed to be pre-formed with a specific configuration that matches the anatomical structure of the vertebra. The claws are pre-positioned to engage with bony landmarks, eliminating the need for complex intraoperative adjustments and reducing surgical time while maintaining reliable fixation.
2Strength
If bone screws are used to secure spinal rods, then stable fixation is achieved, but the procedure requires substantial hardware and surgical complexity
Solution Approach 1:
The invention extracts and eliminates the need for threaded fasteners, drill bits, and complex locking mechanisms associated with traditional bone screws. The clamp device achieves fixation through direct mechanical engagement of the claws with the vertebra, simplifying the hardware required while maintaining adequate fixation strength for spinal stabilization.
Solution Approach 2:
Instead of inserting fasteners into drilled holes through the bone (the conventional approach), the clamp device inverts the approach by having pre-formed claws that wrap around and engage with external bony landmarks. This reversal of the fixation mechanism simplifies the hardware design and reduces the number of components needed.
3Stability of the object's composition
If traditional fixation methods are used on small or damaged vertebrae, then spinal stability can be achieved, but the risk of bone damage and surgical difficulty increase
Solution Approach 1:
The clamp device is designed with claws of varying sizes and shapes that can be selected to match specific vertebral anatomies, including small or damaged vertebrae. Each claw can be optimized for its local engagement point, distributing forces appropriately and reducing the risk of further bone damage while achieving the necessary spinal stability.
Solution Approach 2:
The clamp device incorporates adjustable claws that can be positioned and secured at different locations on the vertebra. This dynamic adaptability allows the surgeon to optimize the fixation points based on the specific anatomical conditions of each vertebra, whether normal, small, or damaged, thereby achieving stable fixation while minimizing bone damage risk.
Data Source
AI summary
A clamp device includes multiple claws for collectively gripping a vertebra, particularly over a pars interarticularis. At least one of the claws is movable relative to a body of the clamp device. The movable claw includes an elongate tab received within a track extending within the body. The body or the tab includes a threaded hole within which set screws may be received for immobilizing the movable claw relative to the body. The clamp device also includes an array of rod clamps. The rod clamps are supported by the body, and more directly by a bar supported by the body. The bar is releasably connectable to the body, and the rod clamps are pivotably connectable to the bar.