K Number
K193540
Date Cleared
2020-06-16

(179 days)

Product Code
Regulation Number
888.3560
Panel
OR
Reference & Predicate Devices
AI/MLSaMDIVD (In Vitro Diagnostic)TherapeuticDiagnosticis PCCP AuthorizedThirdpartyExpeditedreview
Intended Use

The TruMatch Patient Specific Instruments are intent-specific surgical instrumentation to assist in the positioning of a joint replacement component intra-operatively and in guiding the marking of bone before cutting. The anatomical landmarks necessary for the TruMatch Patient Specific Instruments must be present and identifiable on CT. The TruMatch Patient Specific Instruments are intended for use with Sigma Total Knee Implants and Attune Total Knee Implants and their cleared indications for use. The TruMatch Patient Specific Instruments are intended for single use only.

Intended for patients with osteoarthritis who: Meet the criteria for primary total knee replacement performed with a measured resection technique. Have mild bone deformities and/or angular deformities less than 15 degrees of fixed varus/valgus, or flexion. Have some previous implants, such as hip implants, ankle implants, and soft tissue anchors. Contralateral knee replacement is acceptable as long as the contralateral knee is flexed away (not within the same medial/lateral axis) from the knee of interest during the CT scan.

Device Description

The TRUMATCH Personalized Solutions System is comprised of patient-specific instruments and the software utilized to design the patient-specific surgical plans and instruments. The predicate TRUMATCH System creates a surgical plan based on a mechanical axis surgical technique. Changes to the Planning software component allow the surgeon to select a mechanical axis surgical technique or a patient-specific alignment surgical technique. Upon approval of the surgical plan, the TRUMATCH Guides are manufactured according to the plan.

AI/ML Overview

The document describes the DePuy TRUMATCH Personalized Solutions, which are patient-specific surgical instruments for total knee replacement. The 510(k) submission (K193540) is for a modification to the software that enables the TRUMATCH surgical plan and Guides to be designed for a patient-specific alignment surgical technique, in addition to the existing mechanical axis technique.

Here's a breakdown of the acceptance criteria and the study that proves the device meets them, based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance:

The document does not explicitly state quantitative acceptance criteria for the performance of the TRUMATCH Personalized Solutions. Instead, it relies on demonstrating substantial equivalence to a legally marketed predicate device (TRUMATCH Personalized Solutions, K110397). The "performance data" section focuses on non-clinical tests to support this equivalence.

However, based on the described studies, the implied acceptance criteria for the modified software and guides would be:

Acceptance Criteria (Implied)Reported Device Performance
Model Creation Process Verification: The software accurately models patient anatomy and generates patient-specific guides for patient-specific alignment."Model creation process verification for Patient Specific Alignment Guides" was performed, indicating the process was verified to be acceptable.
Guide Fit: The patient-specific guides fit accurately on the bone."Cadaver lab with simulated surgery for assessment of guide fit" was performed, indicating the fit was acceptable.
Implant Alignment: The guides accurately facilitate the alignment of the implant."Cadaver lab with simulated surgery for assessment of... implant alignment" was performed, indicating acceptable alignment.
Implant Size: The guides assist in selecting the correct implant size."Cadaver lab with simulated surgery for assessment of... implant... size" was performed, indicating acceptable sizing.
Bone Resection Accuracy: The guides lead to accurate bone resections."Cadaver lab with simulated surgery for assessment of... bone resection accuracy analysis" was performed, indicating acceptable accuracy.
Software Functionality: The software performs as intended, including enabling patient-specific alignment."Software verification testing" was performed, indicating the software was verified to function correctly.

2. Sample Size Used for the Test Set and Data Provenance:

  • Test Set Sample Size: The document does not specify the exact sample size for the cadaver lab (how many cadavers or knees were used). For the model creation process verification and software verification testing, no specific sample size (e.g., number of models or software tests) is provided.
  • Data Provenance: Not explicitly stated. The studies are non-clinical (cadaver lab, software testing), so country of origin for the data is less relevant than for clinical trials. The description suggests these were internal verification studies.

3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications:

The document does not provide details on the number of experts or their qualifications used to establish ground truth for the non-clinical studies. For the cadaver lab, it's implied that observations and measurements were made, likely by qualified personnel (e.g., orthopedic surgeons or biomechanical engineers), but this is not specified.

4. Adjudication Method for the Test Set:

The document does not specify any adjudication method (e.g., 2+1, 3+1). For non-clinical, objective measurements these methods are often not used as an established "ground truth" might be derived from direct measurements or engineering specifications.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done:

No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done. The document explicitly states: "No clinical tests were conducted to demonstrate substantial equivalence." The studies performed were non-clinical, focusing on the technical performance of the device and software. Therefore, there's no reported effect size regarding human readers improving with AI vs. without AI assistance, as this device does not involve "readers" in the diagnostic sense, nor does it present AI as an assistive tool to human interpretation in the way radiological AI does.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done:

The "model creation process verification" and "software verification testing" can be considered evaluations of the standalone performance of the algorithm/software, as they assess its ability to generate models and perform functions independently. However, the TRUMATCH Personalized Solutions is inherently a human-in-the-loop system (the surgeon uses the guides). The software creates the plan, but the surgical execution involves human intervention. The cadaver lab assessed the overall system (guides + human interaction).

7. The Type of Ground Truth Used:

  • For the model creation process verification, the ground truth would likely be established based on the accuracy of the generated models against the input CT data and predefined geometric specifications.
  • For the cadaver lab, the ground truth for "guide fit, implant alignment and size, and bone resection accuracy analysis" would typically be established through direct measurements using precise instruments (e.g., micrometers, optical tracking systems, or specialized jigs) on the cadaveric specimens, compared to the planned surgical outcomes.
  • For software verification testing, the ground truth would be against predetermined software requirements and specifications.

8. The Sample Size for the Training Set:

The document does not specify a training set sample size. This device is related to patient-specific instruments designed from CT imaging. While there might have been internal data used for the development and training of the algorithms within the TRUMATCH software system (prior to this specific modification), this submission does not explicitly detail that "training set" information. It focuses on the verification of the modified software and system.

9. How the Ground Truth for the Training Set Was Established:

As no training set information is provided in the document for this specific submission, the method for establishing its ground truth is also not described. For systems that use machine learning or AI, training data ground truth is often established by expert annotation or labeling of a large dataset.

§ 888.3560 Knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis.

(a)
Identification. A knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace a knee joint. The device limits translation and rotation in one or more planes via the geometry of its articulating surfaces. It has no linkage across-the-joint. This generic type of device includes prostheses that have a femoral component made of alloys, such as cobalt-chromium-molybdenum, and a tibial component or components and a retropatellar resurfacing component made of ultra-high molecular weight polyethylene. This generic type of device is limited to those prostheses intended for use with bone cement (§ 888.3027).(b)
Classification. Class II.