Bi-Spring Surgical Impact Tool Reducing Surgeon Fatigue

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing surgical impact tools, such as those used for orthopedic procedures, often require manual hammering or pneumatic systems, which can be tiring for surgeons and cause joint stress, while pneumatic tools are inconvenient and limit tool orientation.

Innovation Solution

A bi-spring surgical impact tool is designed with a housing, a drive rod, a shuttle, a pinion, and first and second springs. The pinion translates the shuttle linearly along the drive rod, and when the pinion and shuttle are out of mesh, the springs move the shuttle to generate impact forces, eliminating the need for manual hammering or pneumatic systems.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If manual hammering is used to transmit impact force, then the tool can be simple in structure, but the surgeon experiences physical fatigue and joint stress

Engineering Contradiction:
Improvetool structureVSAvoidsurgeon fatigue
Core Design Contradiction:
Device complexityVSEase of operation

Solution Approach 1:

The patent replaces the manual mechanical hammering system with an automated spring-based impact mechanism. The surgical impact tool uses a spring-driven shuttle system that automatically generates impact forces, eliminating the need for the surgeon to manually wield a hammer while maintaining the mechanical impact function on the bone.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The spring mechanism serves itself by automatically generating and delivering impact forces without continuous external input. Once the spring is compressed, it self-actuates to propel the shuttle forward, creating impact forces independently without requiring the surgeon to repeatedly apply manual force.

Inventive Principle:
Principle #25Self-service

2Ease of operation

If pneumatic impact tools are used to eliminate manual hammering, then surgeon fatigue is reduced, but the tool requires connection to air hose which limits orientation and convenience

Engineering Contradiction:
Improvesurgeon fatigueVSAvoidtool orientation
Core Design Contradiction:
Ease of operationVSAdaptability or versatility

Solution Approach 1:

The patent replaces the pneumatic system with a spring-based mechanical system. This substitution eliminates the need for air hose connections, allowing the tool to be used in various orientations and positions without being constrained by pneumatic supply lines, thereby improving adaptability while maintaining ease of operation.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent extracts and removes the air hose connection requirement from the system. By eliminating the pneumatic component entirely and using a self-contained spring mechanism, the tool gains freedom of movement and orientation without being tethered to an external air supply.

Inventive Principle:
Principle #2Taking out (Extraction)

3Adaptability or versatility

If spring mechanism is used to generate impact force, then tool portability and adaptability improve, but the device complexity increases compared to manual hammering

Engineering Contradiction:
Improvetool portabilityVSAvoiddevice structure
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent employs a nested arrangement where the shuttle is positioned within the housing, and the spring is contained within the same structure. The pinion gear is integrated into the housing, and all components are compactly arranged to fit within a handheld tool form factor, minimizing overall size while maintaining functional complexity.

Inventive Principle:
Principle #7Nested doll (Nesting)

Solution Approach 2:

The patent combines multiple functions into integrated components. The housing serves as both the structural enclosure and the mounting structure for the spring and shuttle. The pinion gear integrates rotational motion from the trigger mechanism with linear motion of the shuttle, merging gear transmission and linear actuation functions into a single integrated system.

Inventive Principle:
Principle #5Merging (Combining)

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 bi-spring surgical impact tool reduces the physical strain on surgeons by providing a consistent and controlled impact force, allowing for more precise and efficient surgical procedures without the inconvenience of pneumatic systems.

Implementation Method 1

a first spring mechanically coupling the first end of the housing to the first end of the shuttle... and a second spring mechanically coupling the second end of the housing to the second end of the shuttle... wherein when the shuttle is out of position to allow the plurality of shuttle teeth to mesh with the plurality of pinion teeth, the shuttle is movable by the first and second springs

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP4243715B1BI-spring surgical impact tool
Publication Date: 2025.04.23 ZIMMER INC
  • EP4243715B1 patent drawingFigure 1
  • EP4243715B1 patent drawingFigure 2
  • EP4243715B1 patent drawingFigure 3

AI summary

Disclosed herein are bi-spring surgical impact tools and methods of use thereof. The bi-spring surgical impact tools can include a housing, a shuttle, a pinion, and first and second springs. The housing can define a cavity having a first end and a second end. The shuttle can be located within the cavity and define a plurality of indentations. The pinion can be located proximate the shuttle and have a plurality of protrusions sized to mesh with the plurality of indentations during rotation of the pinion. The first and second springs can be mechanically coupled to the housing and the shuttle. Rotation of the pinion in a first direction can translate the shuttle in a first direction towards the first end of the housing and rotation of the pinion in a second direction can translate the shuttle in a second direction towards the second end of the housing.