Patient-Specific Orthopaedic Instruments Using Additive Manufacturing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current orthopaedic surgical instruments are generic and reusable, failing to provide precise fit and alignment for individual patient anatomy, which can lead to suboptimal surgical outcomes in procedures like knee and hip replacements.

Innovation Solution

Customized patient-specific surgical instruments with negative contours matching the patient's femoral condyles and intercondylar notch, featuring a cutting guide slot and augment for secure positioning and precise resection, utilizing additive manufacturing techniques like Direct Metal Laser Sintering for precise anatomical fit.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If generic reusable orthopaedic surgical instruments are used, then device complexity is reduced and ease of manufacture is improved, but manufacturing precision and measurement precision deteriorate due to inability to match individual patient anatomy

Engineering Contradiction:
Improveanatomical fit precisionVSAvoidinstrument customization
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

Patient-specific instruments are manufactured before surgery based on pre-operative imaging data (CT or MRI scans). The instruments incorporate patient-specific anatomical surface contours that are determined and fabricated in advance, allowing precise fitting to the individual patient's anatomy without requiring complex intraoperative adjustments.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patient-specific instruments include bone-contacting surfaces that are negative impressions or copies of the patient's actual bone surface geometry. These copied surfaces are created from digital models derived from medical imaging, enabling the instrument to match the unique anatomical features of the patient's femur or tibia for highly precise alignment and positioning.

Inventive Principle:
Principle #26Copying

2Measurement precision

If customized patient-specific surgical instruments are used, then manufacturing precision and surgical accuracy are improved, but ease of manufacture deteriorates due to requirement for additive manufacturing and patient-specific design

Engineering Contradiction:
Improvealignment accuracyVSAvoidinstrument fabrication
Core Design Contradiction:
Measurement precisionVSEase of manufacture

Solution Approach 1:

The invention utilizes additive manufacturing technology (such as Direct Metal Laser Sintering) to fabricate complex patient-specific geometries that would be difficult or impossible to produce using traditional manufacturing methods. This manufacturing parameter change enables the production of instruments with highly customized anatomical surfaces while maintaining structural integrity and precision.

Inventive Principle:
Principle #35Parameter changes

3Reliability

If generic surgical instruments are used, then ease of operation is maintained through standardization, but reliability deteriorates due to suboptimal fit and alignment for individual patient anatomy

Engineering Contradiction:
Improvesurgical outcome consistencyVSAvoidinstrument positioning
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The patient-specific instruments incorporate localized anatomical matching features at critical bone-contacting surfaces, such as the posterior condyles of the femur and the tibial plateau. These localized customizations ensure precise positioning and alignment at key anatomical landmarks while the rest of the instrument structure can maintain standardized features for ease of manufacture and operation.

Inventive Principle:
Principle #3Local quality

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

Enables precise alignment and resection of bones during orthopaedic surgeries, reducing surgical complexity and improving the accuracy of prosthetic implantation by matching the unique anatomy of each patient, thus enhancing surgical precision and patient-specific outcomes.

Implementation Method 1

utilizing additive manufacturing techniques like Direct Metal Laser Sintering for precise anatomical fit

Methodology Applied
Scientific EffectLaser Sintering: Selective Laser Sintering

Data Source

PatentEP3801303B1Customized patient-specific orthopaedic surgical instruments
Publication Date: 2023.07.05 DEPUY SYNTHES PROD INC
  • EP3801303B1 patent drawingFigure 1
  • EP3801303B1 patent drawingFigure 2~3
  • EP3801303B1 patent drawingFigure 4~5

AI summary

An orthopaedic surgical instrument is provided having a first customized patient-specific surgical instrument and a second customized patient-specific surgical instrument configured to be removably coupled to the first customized patient-specific surgical instrument. The second customized patient-specific surgical instrument includes a body positioned in a gap defined between posteriorly-extending arms of the first customized patient-specific surgical instrument.