External Fixation Device with Curvilinear Guide

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current external fixation devices for bone articulations, particularly those involving finger joints, are ineffective and imprecise in restoring the non-contracted state of flexor tendons, leading to potential deformation or incorrect lengthening of bone elements, and are cumbersome for application across all joints.

Innovation Solution

An external fixation device with a guide element and fastening members equipped with threaded pins and a lead nut and screw mechanism, allowing precise adjustment of bone elements' angle and movement, enabling precise restoration of bone structure and alignment.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If elastic attachments are used to apply traction to bone elements, then the flexor tendon can be stretched, but the device becomes cumbersome and imprecise in controlling bone element positioning

Engineering Contradiction:
Improvetendon stretching effectivenessVSAvoiddevice structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The device divides the fixation system into separate modular components: a fixation body with threaded pins for bone attachment, a独立的 guide element with curvilinear guide, and fastening members with lead nuts. This segmentation allows each component to perform its specific function precisely while simplifying the overall device structure and making it less cumbersome.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention replaces the traditional elastic attachment mechanism with a mechanical screw-based system. The lead nut and screw mechanism provides precise, controlled traction through threaded engagement, eliminating the need for elastic materials and providing accurate positioning control through the curvilinear guide geometry.

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

2Manufacturing precision

If traditional elastic devices are used for bone traction, then tendon lengthening is attempted, but the positioning precision of bone elements deteriorates

Engineering Contradiction:
Improvebone element positioning precisionVSAvoidtendon restoration accuracy
Core Design Contradiction:
Manufacturing precisionVSReliability

Solution Approach 1:

The guide element acts as an intermediary component between the fastening members and the bone elements. Its curvilinear guide provides a precisely defined trajectory that constrains the movement of fastening members, ensuring accurate and controlled positioning of bone elements during tendon restoration while maintaining reliable traction.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Adaptability or versatility

If complex elastic fixation devices are applied, then tendon traction is achieved, but the device cannot be applied to all joints due to its bulk

Engineering Contradiction:
Improvejoint applicabilityVSAvoiddevice structure
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The device is divided into separate modular components (fixation body, guide element, fastening members) that can be independently sized and configured. This segmentation allows the device to be adapted to different joint sizes and anatomical locations, from small finger joints to larger joints, making it universally applicable while maintaining a simple overall structure.

Inventive Principle:
Principle #1Segmentation

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 allows for precise and simple adjustment of bone articulation angles, effectively treating degenerative tendon diseases and bone disorders, enabling independent patient therapy and application across various joints without deformation risks.

Implementation Method 1

threaded pins and a lead nut and screw mechanism, allowing precise adjustment of bone elements' angle and movement

Methodology Applied
Scientific EffectScrew mechanism: Screw

Data Source

PatentEP2723258B1External fixation device
Publication Date: 2016.12.28 CITIEFFE SRL
  • EP2723258B1 patent drawingFigure 1~2
  • EP2723258B1 patent drawingFigure 3~4b
  • EP2723258B1 patent drawingFigure 5~6

AI summary

A device for the external fixation of a first bone element (01) and a second bone element (02) articulated to each other, comprises: a guide member (2) equipped with a curvilinear guide (3); a first fastening member (7) slidably associated with the guide (3) and equipped with first means (9) for releasable fastening to the first bone element (01); a second fastening member (10) associated with the guide member (2) and equipped with first means (11) for releasable fastening to the second bone element (02); and relative movement means (14) by which the first fastening member (7) is moved relative to the second fastening member (10) along the guide (3).