Steerable Bone Cement Injection Device for Vertebral Fractures
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current bone cement delivery systems for vertebroplasty and kyphoplasty procedures lack rapid and controllable deployment capabilities, leading to inefficiencies in stabilizing vertebral compression fractures and requiring frequent revisions due to cement degradation.
Innovation Solution
A steerable and curvable injection device with a tubular body and deflectable distal portion, allowing for precise placement and controlled injection of bone cement into vertebral bodies, using a two-step injection process with varying inorganic bone particle concentrations and a spiral mixing nozzle for optimal viscosity and rapid hardening.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional bone cement delivery systems are used, then the procedure can be performed, but the deployment of bone cement is not rapid or controllable enough
Solution Approach 1:
The injection system employs a dynamic control mechanism where the proximal portion of the injector remains stationary while the distal portion can be deflected and positioned independently. This allows the operator to control the direction and placement of bone cement deployment dynamically, achieving both rapid deployment and precise controllability during the vertebroplasty procedure.
Solution Approach 2:
The injector is divided into distinct segments: a proximal stationary portion and a distal deflectable portion. This segmentation allows independent control of each section, enabling rapid advancement of the needle while maintaining controllability through the deflection mechanism at the distal end for precise bone cement injection.
2Strength
If bone cement is injected to stabilize vertebral fractures, then structural support is provided, but cement migration and porosity occur
Solution Approach 1:
The system replaces traditional mechanical injection methods with a controlled deflection mechanism that uses a flexible distal portion to precisely direct bone cement flow. This allows the operator to control cement placement accuracy by deflecting the distal tip to the desired angle, preventing migration and reducing porosity while maintaining structural support.
Solution Approach 2:
The deflection angle of the distal portion can be adjusted to change the direction and precision of bone cement injection. By varying the deflection parameter, the operator can optimize cement placement precision for different vertebral anatomy and fracture patterns, ensuring proper structural support without migration.
3Reliability
If PMMA is injected through a needle into cancellous bone, then the vertebra is stabilized, but the procedure requires frequent revisions due to cement degradation
Solution Approach 1:
The system provides visual feedback through radiopaque markers on the injector that allow real-time monitoring of needle and cement placement. This feedback mechanism enables the operator to ensure precise placement of bone cement in the optimal locations within the vertebral body, maximizing structural support and minimizing degradation that would lead to revisions.
Solution Approach 2:
The deflection mechanism allows preliminary positioning and angulation of the distal injector tip before bone cement injection begins. This preliminary action ensures that the cement is placed precisely in the intended location from the start, optimizing structural support and reducing the need for revision surgeries due to improper placement or degradation.
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 efficient and controlled deployment of bone cement, providing structural support and pain relief while minimizing cement migration and porosity, thereby extending the clinical life of the cement and reducing the need for revision surgeries.
Implementation Method 1
A pull wire extendable through a central lumen of the shaft is secured with respect to the shaft distally of the transverse slots. Axial proximal retraction of the pull wire causes lateral deflection of the distal portion of the shaft away from a longitudinal axis of the shaft.
Implementation Method 2
When the powder and liquid monomer are mixed, an exothermic polymerization takes place resulting in the formation of a 'dough-like' material
Implementation Method 3
Polymethylmethacrylate (PMMA) is injected through the needle and into the cancellous-bone space of the vertebra. When the powder and liquid monomer are mixed, an exothermic polymerization takes place
Data Source
Figure 1~3
Figure 4
Figure 5
AI summary
Methods and devices for augmenting bone, such as in performing vertebroplasty are disclosed. A bone cement injection needle is provided, having a laterally deflectable distal end. Systems are also disclosed, including the steerable and curvable injection needle, introducer and stylet. The system can also include various exit ports that can be configured with clog-resistant features, such as an obturator. Steerable cavity creation systems and methods are also disclosed.