Monolithic Surgical Saw Blade with Proximal Pivot
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing surgical saw blades with translation mechanisms are mechanically inefficient, cause friction, and result in unstable cutting angles, leading to reduced efficiency and increased risk of inaccurate bone cuts due to bucking or 'kicking', which can expose adjacent soft tissue to harm.
Innovation Solution
A saw blade assembly with an elongate monolithic blade and a sheath that engages bone at a shallow angle, minimizing bucking and protecting soft tissue, featuring a unitary construction with no moveable parts and a sheath to enclose the blade, reducing exposure to high-speed oscillation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If translation mechanisms with moving internal parts are used to limit midline oscillatory excursion, then soft tissue protection is improved, but device complexity increases and mechanical efficiency decreases due to friction
Solution Approach 1:
The patent removes the complex translation mechanism from the saw blade assembly, extracting the problematic moving internal parts that caused friction and inefficiency. The blade is directly coupled to the oscillating driver without intermediate translation components, eliminating the source of mechanical losses while maintaining controlled cutting through direct power transmission.
Solution Approach 2:
The patent introduces a sheath as an intermediary component that encloses the blade and provides soft tissue protection. Rather than using complex translation mechanisms to limit blade excursion, the sheath acts as a protective barrier that confines the cutting action, reducing harmful effects to surrounding tissues while allowing the blade to operate efficiently.
2Manufacturing precision
If translation mechanisms are used to limit oscillatory excursion, then cutting accuracy is improved, but energy loss increases due to friction between moving parts
Solution Approach 1:
The translation mechanism is completely removed from the system, eliminating the moving parts that generated frictional energy losses. The blade receives oscillatory motion directly from the driver, ensuring that nearly all input energy is transmitted to the cutting edge without being dissipated through intermediate mechanical components.
3Ease of operation
If distally disposed pivot point is used, then blade can engage bone, but cutting stability deteriorates due to sharp and unstable engagement angle causing bucking and kicking
Solution Approach 1:
The patent inverts the traditional pivot point location from the distal end to the proximal end of the blade. This proximal pivot point configuration fundamentally changes the blade's engagement geometry with bone, creating a more stable cutting angle that prevents bucking and kicking while maintaining effective bone engagement capability.
4Manufacturing precision
If tighter grip is maintained on powered saw to control instability, then cutting accuracy is improved, but surgeon fatigue increases
Solution Approach 1:
By inverting the pivot point location to the proximal end, the blade's cutting action becomes inherently more stable and easier to control. This design change reduces the surgeon's physical effort required to maintain control during cutting operations, decreasing fatigue while preserving or improving cutting accuracy through the more stable engagement geometry.
Data Source
Figure 1A~1B
Figure 2A~2B
Figure 2C~2D
AI summary
A saw blade assembly for use with a driver having an oscillatory drive member comprises an elongate sheath and an elongate monolithic blade. The sheath's proximal end is removably mountable on the driver. The sheath has an open interior which receives the blade. The blade's proximal end is pivotably mounted to the sheath's proximal end. The blade's distal cutting end extends out of the sheath's distal end and is transverse to the blade's central longitudinal axis. When cutting bone, the drive member pivots the blade's cutting end back and forth in an arc about a pivot point at the blade's proximal end while the driver holds the sheath stationary to protect surrounding tissues from the motions of the remainder of the blade. The long pivot radius between the proximal pivot point and the distal cutting end contributes to minimizing the angle of engagement of the cutting end to the bone.