Endoscopic Stapler Staggered Cam Rotational Ejection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing surgical staplers for endoscopic use are limited by their large diameter and inability to effectively suture thicker tissues, necessitating a need for smaller diameter staplers that can handle thicker tissues efficiently.
Innovation Solution
A surgical stapler design featuring a tool assembly with a cartridge and anvil, utilizing staggered cam members and staples with staggered legs and D-shaped configurations, allowing for rotational ejection and enhanced tissue suturing capabilities in a small diameter format.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a small diameter tool assembly is used for endoscopic stapling, then the invasiveness to the patient is minimized, but the ability to suture thicker tissues is compromised
Solution Approach 1:
The staple is divided into two separate legs that are staggered relative to each other, with each leg independently engaging the cam member. This segmentation allows the staple to achieve greater deformation and penetration capability for thicker tissues while maintaining a compact overall structure suitable for small diameter tool assemblies
Solution Approach 2:
The staple legs are configured in a staggered arrangement along the longitudinal axis, creating a three-dimensional configuration rather than a simple planar structure. This dimensional change enables the staple to engage tissue more effectively and provides the necessary mechanical advantage for suturing thicker tissues through the intermediate portion's offset connection points
2Device complexity
If traditional staple ejection mechanisms are used, then the device structure remains simple, but the rotational ejection capability needed for staggered leg staples is not achieved
Solution Approach 1:
The cam member is configured with asymmetric cam surfaces that engage the staggered staple legs at different positions and angles. This asymmetric design enables the rotational ejection motion by creating unequal leverage on the two legs, causing the staple to rotate as it is ejected from the cartridge
Solution Approach 2:
The cam member translates linear firing motion into rotational staple ejection through its cam surface geometry. The dynamic interaction between the cam surfaces and staggered legs creates a rotating ejection path, allowing the staple to pivot and rotate during ejection without requiring a complex dedicated rotation mechanism
3Adaptability or versatility
If staples with intermediate portions having axially offset connection points are used, then rotational ejection and thicker tissue suturing are enabled, but the staple manufacturing complexity increases
Solution Approach 1:
The intermediate portion is designed with specific geometric parameters including the axial offset distance between connection points and the S-shape configuration. By optimizing these parameters, the staple achieves the necessary rotational ejection capability and tissue penetration strength while remaining manufacturable through conventional forming processes
Data Source
AI summary
A surgical stapler is described herein which includes a shaft portion and a tool assembly supported on a distal end of the shaft portion. The tool assembly includes an anvil and a cartridge body which rotatably supports a plurality of staples within notches. At least one firing cam is provided to sequentially to engage and rotate each of the staples to fire the staples from the cartridge body. Each of the staples includes first and second legs axially offset from each other and interconnected by an intermediate portion. At least one firing cam is provided to sequentially to engage and rotate each of the staples to fire the staples from the cartridge body. The at least one firing cam includes axially offset cam members.