Surgical Scissors Cam Actuation and Compression Grip
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Solution Overview
Problem
Current surgical scissors devices used in minimally invasive procedures, such as endoscopic surgeries, face challenges in maintaining tissue grip and requiring significant force to open and close the blades, leading to potential tissue slipping and increased clinician effort.
Innovation Solution
The surgical scissors device features cam-actuated blade members held in compression by a fastener, utilizing a clamp mechanism to apply and maintain compressive force, allowing for easier opening and closing while minimizing tissue slipping, and incorporating a flexible shaft to distribute forces effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If blade members are held in compression by a fastener with a clamp mechanism, then tissue grip is improved and tissue slipping is prevented, but device complexity increases due to additional clamp members and mechanisms
Solution Approach 1:
The blade member is divided into two separate blade members (first and second blade members) that can be independently positioned and compressed against each other. This segmentation allows for independent control and compression of each blade, improving tissue grip while maintaining manageable complexity through modular design
Solution Approach 2:
The clamp mechanism merges multiple functions into a single integrated system: the first and second clamp members work together with the fastener to simultaneously compress both blade members, providing stable tissue grip for both cutting edges while reducing the number of separate mechanisms needed
2Ease of operation
If cam mechanism is used to actuate blade members, then mechanical advantage is enhanced and operating force is reduced, but device complexity increases due to cam grooves and pin features
Solution Approach 1:
The cam mechanism utilizes curved cam grooves and corresponding pin features that convert rotational or linear motion into the opening and closing motion of blade members. The curved geometry provides mechanical advantage by varying the leverage throughout the motion cycle, reducing the force required to operate the scissors while maintaining a relatively simple integrated mechanism
Solution Approach 2:
The cam mechanism acts as an intermediary between the user's operating motion and the blade member movement. The cam grooves and pin features translate the user's input force into amplified blade closing force, reducing the direct operating force needed while keeping the mechanism integrated into the handle assembly
3Reliability
If blade members are held in compression during use, then tissue slipping is prevented, but force required to open and close blades increases
Solution Approach 1:
The clamp mechanism is designed to dynamically adjust the compression force on blade members during operation. The fastener and clamp members can be positioned to provide optimal compression during tissue grasping, while the cam mechanism provides mechanical advantage during opening and closing to reduce the peak force required, balancing tissue grip with operational ease
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
The device enhances mechanical advantage, reducing the force required to operate the scissors and preventing tissue slipping, thereby improving efficiency and precision during endoscopic procedures.
Implementation Method 1
The blade members may be cam actuated, allowing increased mechanical advantage, allowing the clinician to more easily open and close the blade members
Implementation Method 2
The blade members may be held in compression relative to one another by a fastener. This may tend to hold the blade members together during use and prevent or minimize tissue slipping between the scissor blades
Implementation Method 3
incorporating a flexible shaft to distribute forces effectively
Data Source
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AI summary
Surgical scissors devices are disclosed. The surgical scissors devices may comprise an end effector with first and second blade members. The first and second blade members may respectively comprise proximally positioned cams and distally positioned blade ends. Also, the first and second blade members may be coupled at a pivot point by a fastener held in tension along its longitudinal axis by the blade members. A reciprocating shuttle may comprise at least one pin positioned within slots defined by the respective cams of the blade members. Distally- directed motion of the shuttle may cause the first and second blade members to open and proximally-directed motion of the shuttle may cause the first and second blade members to close. Methods and apparatuses for forming the surgical scissors device are also disclosed.