Surgical Instrument Safety Lever Prevents Premature Staple Firing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing surgical stapling instruments for circular anastomosis and hemorrhoid treatment lack a reliable safety mechanism to prevent premature firing of staples, which can lead to improper tissue handling and reduced efficacy in procedures.
Innovation Solution
A surgical instrument with a safety mechanism that includes a lever movable between two positions, where it prevents or enables the firing trigger, ensuring staples are only fired when the anvil head and staple holding component are properly approximated, featuring a latch system and biased components to maintain the safety position until tissue is correctly clamped.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a safety mechanism is added to prevent premature firing, then reliability is improved, but device complexity increases
Solution Approach 1:
The safety mechanism performs preliminary verification that the anvil and jaw are properly approximated before allowing the firing trigger to be actuated. This preliminary action ensures that the stapling conditions are met before the firing sequence is enabled, preventing premature or incorrect staple firing while maintaining a relatively simple mechanical design through the use of a safety lever and latch system.
2Ease of operation
If the firing trigger is always enabled, then ease of operation is improved, but reliability deteriorates due to premature firing risk
Solution Approach 1:
The firing trigger's enablement state is made dynamic rather than static. The safety lever automatically transitions between blocked and enabled positions based on the approximation status of the anvil and jaw. When properly approximated, the lever moves to enable the firing trigger; when not approximated, it blocks the trigger. This dynamic control maintains ease of operation when conditions are met while preventing premature firing when conditions are not met.
Solution Approach 2:
The safety mechanism incorporates feedback from the approximation mechanism's position into the firing trigger's enablement state. The safety lever is actuated by the approximation mechanism, creating a feedback loop where the physical state of the anvil-jaw approximation directly controls whether the firing trigger can be actuated. This feedback ensures that the trigger is only enabled when the necessary approximation has been achieved.
3Ease of operation
If the safety lever is resettable, then ease of operation is improved, but reliability deteriorates due to potential re-firing errors
Solution Approach 1:
The safety lever's resetting function is extracted from the approximation mechanism and assigned to a separate reset button on the handle. This separation allows the lever to be reset independently of the anvil-jaw approximation state. The reset button mechanically returns the safety lever to its blocked position, ensuring that even if the approximation is undone, the firing trigger remains blocked. This extraction of the reset function prevents re-firing errors while maintaining ease of operation.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A surgical instrument (10) including a handle assembly (12), a safety mechanism (200), an elongated body portion (14) and a head portion (16) is disclosed. The handle assembly includes a stationary handle (18), an approximation mechanism (22), and a firing trigger (20). A lever (210) of the safety mechanism (200) is movable between a first position where the firing trigger is prevented from being actuated, and a second position where the firing trigger is able to be actuated. A first jaw member (30) of the head portion is movable in relation to a second jaw member (31) of the head portion between spaced and approximated positions. Movement of the first jaw member in relation to the second jaw member from the approximated position towards the spaced position causes the lever of the safety mechanism to move from its second position to its first position.