Offset Knife Channel in Endoscopic Forceps
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Endoscopic electrosurgical forceps face challenges in sealing and cutting larger vessels due to the difficulty in advancing a knife through the knife channel, which can lead to wear and tear, especially when the knife blade is not aligned properly with the knife channel, limiting the effectiveness of endoscopic procedures.
Innovation Solution
The design incorporates an offset knife channel and a knife guide with a blade stop mechanism, allowing the knife to extend straight through the channel and preventing binding, while the knife guide is configured to align properly with the jaw members, ensuring smooth translation and reducing wear.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a standard knife channel alignment is used, then the instrument structure is simple, but the knife blade experiences wear and tear due to improper alignment with the knife channel
Solution Approach 1:
The knife channel is positioned offset from the longitudinal axis of the instrument rather than being centrally aligned. This asymmetric positioning allows the knife blade to travel through the channel without contacting the sides, eliminating wear and tear while maintaining structural simplicity
Solution Approach 2:
The knife channel is curved rather than straight, introducing a spatial dimension change that allows the blade to follow a curved path through the tissue. This curved trajectory prevents blade binding and side contact while sealing larger vessels effectively
2Adaptability or versatility
If electrosurgical energy is used to seal larger vessels, then the need for open surgery is reduced, but the knife may bind or wear due to improper alignment
Solution Approach 1:
The offset knife channel positioning creates an asymmetric configuration that provides adequate clearance between the blade and channel walls, allowing smooth knife advancement even when sealing larger vessels with electrosurgical energy
Solution Approach 2:
The knife channel dimensions and curvature are specifically designed to accommodate blades of certain thicknesses while maintaining proper clearance. The channel geometry parameters are optimized to prevent binding during knife advancement through sealed tissue
3Reliability
If the knife channel is offset from the longitudinal axis, then the knife blade does not contact the channel sides reducing wear, but the instrument structure becomes more complex
Solution Approach 1:
The offset knife channel creates an asymmetric layout within the end effector assembly that prevents blade contact with channel sides. Despite the asymmetric positioning, the overall structural complexity is minimized by integrating the channel directly into the jaw members without additional guiding components
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
This configuration facilitates the efficient sealing and cutting of larger vessels during endoscopic procedures, reducing the need for conversion to open surgery and enhancing the durability of the instrument by preventing knife binding and wear.
Implementation Method 1
Electrosurgical forceps utilize both mechanical clamping action and electrical energy to effect hemostasis by heating tissue and blood vessels to coagulate, cauterize and/or seal tissue
Data Source
AI summary
A forceps includes an end effector assembly having first and second jaw members. Each jaw member includes a proximal flange having an inwardly-facing surface. The proximal flanges are coupled to one another for moving the jaw members relative to one another between a first position and a second position for grasping tissue therebetween. The inwardly-facing surfaces of the proximal flanges are disposed in abutting relation relative to one another. A knife is configured to move along a knife path defined along an outwardly-facing surface of one of the proximal flanges. The knife is movable between a retracted position and an extended position, wherein the knife extends between the jaw members to cut tissue grasped therebetween.