Circular Stapler Anvil Concave Buffer for Tissue Dragging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing circular staplers face issues with incomplete cutting of staples and tissue dragging during anastomosis, as the staples often fail to be successfully formed or are torn off due to lateral slipping.
Innovation Solution
The circular stapler design incorporates an annular staple cartridge with a stable ring or concave portion that creates height-differentiated fixing spaces with the anvil assembly, ensuring secure clamping and reducing tissue slipping by forming a buffer between new and severed staples.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional circular stapler with flat anvil and staple cartridge is used, then the structure is simple and easy to manufacture, but the staples cannot be successfully cut off and tissues are dragged during anastomosis
Solution Approach 1:
The anvil assembly incorporates a stable ring with a concave portion that creates a localized depressed area. This local structural variation forms a buffer zone between new and severed staples, providing differential support: the concave area allows proper staple formation while preventing lateral slipping of cut staples, thereby resolving the cutting reliability issue without requiring complete redesign of the entire anvil structure.
Solution Approach 2:
The stable ring introduces a vertical dimension (height difference) to the otherwise flat anvil surface. The concave portion creates a depressed zone that forms a buffer between staple layers, adding spatial differentiation in the vertical direction. This dimensional change enables the cut staples to be properly supported at different heights, preventing dragging and ensuring successful cutting.
2Stability of the object's composition
If the anvil assembly uses a flat surface design, then the manufacturing is simple, but lateral slipping occurs causing tissues to be dragged and staples to be torn off
Solution Approach 1:
Rather than making the entire anvil surface complex, only a localized stable ring with concave portion is added to the otherwise simple flat anvil structure. This local modification creates height-differentiated fixing spaces that provide stable tissue positioning and prevent lateral slipping, while the majority of the anvil maintains its simple flat geometry for ease of manufacture.
Solution Approach 2:
The stable ring with concave portion is pre-formed as an integrated feature of the anvil assembly. This preliminary structural preparation creates the buffer zone and height differentiation in advance, ensuring that when tissues are clamped and stapled, the proper positioning and anti-slipping support are already in place, preventing tissue dragging before it can occur.
3Manufacturing precision
If conventional stapling without height differentiation is used, then the device structure is simple, but cut staples cannot be fixed properly leading to incomplete cutting
Solution Approach 1:
The stable ring with concave portion creates a localized area with different height characteristics. This local quality variation forms a buffer that precisely positions cut staples at appropriate heights, ensuring clean cutting. The rest of the anvil and staple cartridge maintain their conventional simple structures, minimizing the increase in overall device complexity while achieving improved cutting precision.
Solution Approach 2:
The concave portion introduces vertical height differentiation to the flat anvil surface. This dimensional change creates fixed spaces at different heights that precisely accommodate and secure cut staples during the cutting process. The height variation ensures proper staple positioning and cutting precision without requiring complex lateral or radial structural modifications.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A circular stapler includes a staple body and an anvil assembly. The staple body includes an annular staple cartridge and an annular cutter located at a distal end thereof. The anvil assembly includes an annular anvil, an annular cutting pad and an anvil shaft. When the staple body and the anvil assembly are closed, the annular staple cartridge is associated with the annular anvil and the annular cutting pad to form at least two connected fixing spaces having height difference. The circular stapler of the present invention can be used to better fix the severed staples for easily cutting. Besides, it is possible to form a buffer between the tissues near the new formed staples and the tissue near the severed staples in order to avoid lateral slipping, thereby reducing dragging the tissues on the end face of the anvil.