Shadow Imaging Tracking for Surgical Instrument Registration

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current surgical navigation systems for computer-assisted surgery lack accuracy and flexibility, particularly in total knee replacements, due to the need for additional time to check and approve pre-operative plans and the inability to adjust implant positions during surgery.

Innovation Solution

Integration of a shadow imaging tracking system directly with patient-specific instruments, allowing for precise tracking and adjustment of implant positions during surgery, while maintaining the simplicity of patient-matched devices.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If patient specific instruments are used for registration, then registration accuracy is improved, but device complexity increases

Engineering Contradiction:
Improveregistration accuracyVSAvoidinstrument complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent combines the patient specific instrument with an integrated measurement system into a single unified device. The measurement system includes markers directly incorporated into the patient specific instrument, eliminating the need for separate registration devices and reducing overall system complexity while maintaining high registration accuracy.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patient specific instrument serves multiple functions: it acts as both a registration device with integrated measurement markers and as a surgical guide for the actual procedure. This multi-functionality reduces the number of separate devices needed and simplifies the overall surgical workflow.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Productivity

If pre-operative planning is performed with patient specific instruments, then surgical efficiency is improved, but loss of time occurs during plan approval

Engineering Contradiction:
Improvesurgical efficiencyVSAvoidplan approval time
Core Design Contradiction:
ProductivityVSLoss of time

Solution Approach 1:

The measurement system and instrument positioning are prepared in advance during the pre-operative planning phase. By pre-positioning the measurement markers and planning the surgical approach with the patient specific instrument, the actual surgical procedure can proceed without time-consuming setup or approval delays, as the plan is already optimized and ready for execution.

Inventive Principle:
Principle #10Preliminary action

3Measurement precision

If computer assisted surgical systems are used, then measurement precision is improved, but device complexity and cost increase

Engineering Contradiction:
Improveposition measurement accuracyVSAvoidsystem complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent integrates the measurement system directly into the patient specific instrument rather than using a separate computer assisted surgical system. The measurement markers are incorporated into the instrument itself, and the tracking is performed through a simplified optical system that follows the instrument's movement, reducing overall system complexity while maintaining measurement precision.

Inventive Principle:
Principle #5Merging (Combining)

4Ease of operation

If traditional surgical navigation is used, then ease of operation is maintained, but measurement precision deteriorates

Engineering Contradiction:
Improvesurgical workflow simplicityVSAvoidposition tracking accuracy
Core Design Contradiction:
Ease of operationVSMeasurement precision

Solution Approach 1:

The measurement system is merged with the surgical instrument, allowing the surgeon to perform measurements and tracking directly through the instrument being used. This integration eliminates the need for separate navigation equipment and procedures, maintaining surgical workflow simplicity while achieving high measurement precision through the integrated optical tracking of the instrument's position.

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

This solution provides more accurate and flexible positioning of implants during surgery, enabling real-time adjustments for proper ligament balancing and reducing the complexity of the surgical workflow.

Implementation Method 1

The tracking system comprises a shadow imaging tracking system comprising an optical source, a shadow-generating device and a patient specific instrument sensor

Methodology Applied
Scientific EffectShadow imaging: Shadow

Data Source

PatentEP3635342B1A surgical instrument system
Publication Date: 2025.04.23 MEDIVATION AG
  • EP3635342B1 patent drawingFigure 1
  • EP3635342B1 patent drawingFigure 2
  • EP3635342B1 patent drawingFigure 3

AI summary

A surgical instrument system (1) for treatment of an anatomical structure (3, 5) comprises an instrument (8) and/or a patient specific instrument (2, 4) for performing the treatment on the anatomical structure. The instrument (8) and/or the patient specific instrument (2, 4) comprises an integrated measurement system (20, 40, 80) for tracking the instrument (8) and/or the patient specific instrument (2, 4) relative to the anatomical structure (3, 5), whereby the integrated measurement system comprises a tracking system (6, 10), which comprises a shadow imaging tracking system comprising an optical source (10), a shadow-generating device and a patient specific instrument sensor (26) whereby an initial position of the instrument (8) or the patient specific instrument (2, 4) is registerable by the patient specific instrument sensor (26). The shadow-generating device is arranged between the optical source and the imaging device for generating a shadow. The shadow imaging tracking system is configured to compute the elevation of the source from the pattern the shadow casts on the surface of the imaging device. The integrated measurement system comprises an inertial measurement unit (30) configured to determine the position of the patient.