Nanofiber Adhesive Base Pads for Bone-Relative Tracker Stability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing patient trackers used in medical procedures face challenges with skin shift relative to bone or other body parts, making them less accurate, while bone screws are invasive.

Innovation Solution

A tracker system using nanofiber adhesives that adhere to wet tissues like mucosal tissue or periosteum, providing a more fixed location with minimal invasiveness by utilizing absorption, wetting, hydration equilibrium, and macromolecular interpenetration to couple with the tissue.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If skin-based trackers are used, then the tracking system is non-invasive, but the tracker shifts relative to bone reducing accuracy

Engineering Contradiction:
ImproveinvasivenessVSAvoidtracking accuracy
Core Design Contradiction:
Object-affected harmful factorsVSMeasurement precision

Solution Approach 1:

The patent introduces an intermediary tissue layer (mucosal tissue or periosteum) between the tracker and the bone. This intermediary tissue allows the tracker to be positioned closer to the bone for better accuracy while still maintaining a non-invasive attachment method through nanofiber adhesives that bond to the wet tissue surface without penetrating it.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Measurement precision

If bone screws are used, then tracking accuracy is improved by fixing to bone, but the procedure becomes invasive

Engineering Contradiction:
Improvetracking accuracyVSAvoidinvasiveness
Core Design Contradiction:
Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The patent replaces the mechanical fastening system (screws penetrating bone) with a chemical adhesion system (nanofiber adhesives bonding to wet tissue). The nanofibers create strong adhesive bonds through molecular interactions with the tissue's moisture and proteins, eliminating the need for mechanical penetration while achieving comparable fixation strength.

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

3Ease of operation

If traditional adhesives are used, then application is simple, but they fail to adhere properly to wet tissue

Engineering Contradiction:
Improveapplication simplicityVSAvoidadhesion reliability
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The patent changes the fundamental parameters of the adhesive material by using nanoscale fiber dimensions (1-100 nanometers) and hydrophobic chemical compositions. These parameter changes enable the adhesive to interact effectively with wet tissue surfaces through capillary action and hydrophobic interactions, maintaining simplicity of application while achieving reliable adhesion in moist environments.

Inventive Principle:
Principle #35Parameter changes

4Reliability

If nanofiber adhesives are used, then adhesion to wet tissue is achieved, but the device complexity increases

Engineering Contradiction:
Improveadhesion reliabilityVSAvoidadhesive structure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent segments the adhesive into individual nanoscale fibers rather than using a continuous bulk material. This segmentation increases the surface area-to-volume ratio, allowing better interaction with the tissue surface while maintaining a simple overall device structure. The nanofibers can be applied as a thin coating or spray, keeping the application process simple despite the sophisticated material 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 tracker system maintains a stable position relative to bone, minimizing shift during procedures, offering a less invasive and more accurate tracking solution.

Implementation Method 1

The plurality of nanofibers are configured to adhere to wet tissue through fluid absorption

Methodology Applied
Scientific EffectAbsorption: Absorption (physical)

Implementation Method 2

The plurality of nanofibers are configured to adhere to wet tissue through wetting

Methodology Applied
Scientific EffectWetting: Wetting

Implementation Method 3

The plurality of nanofibers are configured to adhere to wet tissue through hydration equilibrium

Methodology Applied
Scientific EffectHydration equilibrium:

Implementation Method 4

The plurality of nanofibers are configured to adhere to wet tissue through macromolecular interpenetration

Methodology Applied
Scientific EffectMacromolecular interpenetration:

Data Source

PatentEP4192386B1Nanofiber adhesives for navigation tracker fixation
Publication Date: 2025.09.24 MEDTRONIC NAVIGATION INC
  • EP4192386B1 patent drawingFigure 1~2
  • EP4192386B1 patent drawingFigure 3~5
  • EP4192386B1 patent drawingFigure 6~13

AI summary

A tracker system (100) for use in image guided surgery is disclosed. The tracker system may couple to wet tissue and may include a navigation tracker (110) and a base pad (120) that couple to each other. The base pad may be fabricated from a plurality of nonwoven nanofibers (122). The base pad is configured to couple to body tissue of a patient via at least one of adsorption, hydration equilibrium, and macromolecular interpenetration.