Multi-Stage Cannula Assembly for Minimally Invasive Spinal Access
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Minimally invasive spinal surgeries face challenges in achieving precise percutaneous access to deep spinal locations and accommodating varying pathology depths, with current methods often requiring open surgery for spacer or connecting element placement, leading to tissue trauma and prolonged recovery.
Innovation Solution
A multi-stage cannula assembly with slidable dilators and cannulae, including a nerve probe dilator and impactor, allows for variable access angles and directions, enabling precise placement of spinal implants by sequentially adjusting the cannula system to match the dimensions of the implant, reducing tissue trauma and avoiding the need for open surgery.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional surgical procedures are used to access deep spinal locations, then direct visualization and implant placement are achieved, but extensive tissue trauma and prolonged recovery time occur
Solution Approach 1:
The access device is divided into multiple stages including a probe, dilators of increasing size, and cannulae that can be inserted sequentially. Each stage prepares the pathway for the next, allowing progressive access to deep spinal locations while minimizing tissue damage at each step.
Solution Approach 2:
The device components are nested within each other - the probe is inserted first, followed by dilators that fit over the probe, and finally cannulae that fit over the dilators. This nested configuration allows minimal access while maintaining the ability to reach deep locations.
2Device complexity
If a fixed-length portal is used for percutaneous access, then the device structure is simplified, but it cannot accommodate varying pathology depths
Solution Approach 1:
The access device incorporates adjustable and extendable components including telescoping dilators and cannulae with variable lengths. The probe can be advanced to different depths and the cannulae can be extended or retracted to match the specific depth requirements of different pathologies, providing dynamic adaptability.
Solution Approach 2:
The device is segmented into multiple adjustable components with variable lengths that can be independently configured. The dilators and cannulae come in different lengths and can be selected or adjusted to match the specific depth of the pathology being treated.
3Stability of the object's composition
If open surgery is performed for spacer placement, then stable fixation is achieved, but tissue destruction and recovery time increase
Solution Approach 1:
The percutaneous access device acts as an intermediary that allows implant placement without requiring open surgery. The multi-stage dilators and cannulae create a controlled pathway through soft tissue, enabling stable fixation of spacers or connecting elements while avoiding the tissue destruction associated with open surgical approaches.
4Object-affected harmful factors
If multi-stage dilators and cannulae are used for percutaneous access, then tissue trauma is reduced, but the device complexity increases
Solution Approach 1:
The access system is divided into distinct functional segments - a probe for initial access, multiple dilators of increasing size for progressive dilation, and cannulae for implant delivery. Each segment has a specific function and can be removed after use, managing complexity through functional segmentation.
Solution Approach 2:
The components are designed to nest within each other in a compact configuration, reducing the overall complexity and storage requirements. The probe fits within the first dilator, which fits within the second dilator, and so on, with the cannulae fitting over the dilators when not in use.
Data Source
AI summary
A cannula assembly for providing percutaneous access in minimally invasive spinal surgeries, includes an outer cannula, a nerve probe dilator and a multistage dilator system comprising a first dilator, a second dilator, a third dilator and a fourth dilator. The outer cannula and the dilators are slidable relative to each other and are arranged sequentially so that the fourth dilator surrounds the nerve probe dilator, the third dilator slides over a surface of the fourth dilator, the second dilator slides over a surface of the third dilator, the first dilator slides over a surface of the second dilator, and the outer cannula surrounds the first dilator.