K Number
K161592
Manufacturer
Date Cleared
2016-11-03

(147 days)

Product Code
Regulation Number
888.3520
Panel
OR
AI/MLSaMDIVD (In Vitro Diagnostic)TherapeuticDiagnosticis PCCP AuthorizedThirdpartyExpeditedreview
Intended Use

Indications for Persona Partial Knee System:

The Persona Partial Knee system is limited to the medial tibiofemoral compartment of the knee intended for patients with painful and/or disabling knee joints due to the following indications:

  • Noninflammatory degenerative joint disease (NIDJD), e.g., osteoarthritis, avascular necrosis;

  • traumatic arthritis;

  • previous tibial condyle or plateau fractures with loss of anatomy or function;

  • varus deformities; and

  • revision of the articular surface of a previously implanted Persona Partial Knee Systemknee surgeries providing that the tibial plate locking mechanism is not compromised and tibial plate components remain well fixed and undamaged.

The Persona Partial Knee System is a single use implantation with bone cement.

Indications for combined Persona Partial Knee System and Zimmer Gender Solutions Patello-Femoral Joint (PFJ):

  • Osteoarthritis, traumatic arthritis, and/or severe chondrocalcinosis of the patellofemoral joint.

  • The salvage of previously failed surgical attempts (e.g., arthroscopy, lateral release, cartilage transplantation).

  • History of patellar dislocation or patella fracture.

  • Dysplasia-induced degeneration.

These indications will be used for the combined medial unicompartmental and patello-femoral implant device, whereby a single condyle and patello-femoral regions have been affected by one or more of these conditions.

Combined Persona Partial Knee System and Zimmer Gender Solutions Patello-Femoral Joint (PFJ) implants are intended for implantation with bone cement.

Device Description

The Persona Partial Knee (PPK) System is a partial knee replacement for the medial compartment of the knee and is modular in design consisting of three components: a unicondylar cobalt-chromium-molybdenum (Co-Cr-Mo) alloy femoral component, a unicondylar titanium (Ti-6Al-4V) alloy tibial tray, and a unicondylar articular surface manufactured using the previously cleared Vivacit-E ® Vitamin-E Highly Crosslinked Polyethylene (VEHXPE).

The Persona Partial Knee System is compatible with the following devices:

  • Zimmer Patellofemoral Joint Prosthesis (K070695)
AI/ML Overview

The provided text is a 510(k) Summary for the Persona Partial Knee System, a medical device. This document focuses on demonstrating substantial equivalence to previously marketed predicate devices, rather than establishing acceptance criteria and proving performance through a standalone study in the way a de novo or PMA submission might.

Therefore, the typical acceptance criteria and study design for validating an AI/ML device's performance are not applicable here. The device is a physical knee implant, not a software algorithm, and the submission does not describe a clinical study in the traditional sense, but rather non-clinical mechanical testing and engineering analyses.

Here's an breakdown based on the information provided, highlighting why many requested points are not present in this type of submission:


1. Table of Acceptance Criteria and Reported Device Performance

This information is not provided in a table format and does not represent clinical "performance" in the sense of accuracy, sensitivity, or specificity as would be expected for an AI/ML device. Instead, it lists mechanical tests and analyses performed to demonstrate the physical device's safety and effectiveness compared to predicates.

Test/Analysis PerformedDescription / Purpose
Femoral Component
Cantilever fatiguePer internal test method
3-Point Bending FatiguePer internal test method
Articular Surfaces
Contact areaPer ASTM F2083
ConstraintPer ASTM F2083 and ASTM F1223
Posterior Crush and Lift OffPer internal test method
WearPer engineering analysis
Static locking mechanism strengthPer internal test method
Tibial Components
3-Point bending fatiguePer internal test method
System Compatibility
Patellar component and PFJ compatibilityPer engineering analysis
MR compatibilityPer engineering analysis
Bacterial Endotoxin Testing (BET)To demonstrate pyrogen limit specifications have been met

Acceptance Criteria: The document states that "Results from mechanical tests and engineering analyses demonstrate the proposed PPK components are substantially equivalent to the predicate devices." While specific numerical acceptance criteria (e.g., maximum deflection, minimum fatigue cycles) are implied by performing these tests to a standard or internal method and achieving "substantial equivalence," they are not explicitly listed in this summary. The general acceptance is that the device performs comparably or better than the predicate devices under these conditions.


Regarding other requested information points:

2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

  • Not applicable. This submission focuses on non-clinical mechanical testing and engineering analyses, not human clinical data or AI/ML model performance on a test set. There isn't a "test set" of patient data in this context.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)

  • Not applicable. This submission relies on engineering and material science principles, not expert consensus on medical images or diagnoses.

4. Adjudication method (e.g. 2+1, 3+1, none) for the test set

  • Not applicable. No adjudication process is described as there is no clinical test set involved.

5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

  • Not applicable. This is a physical implant, not an AI/ML diagnostic or assistive device. No MRMC study was performed. The document explicitly states: "No animal or clinical testing was required to support substantial equivalence."

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done

  • Not applicable. This is a physical medical device, not an algorithm.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)

  • Not applicable / Implied: For the mechanical tests, the "ground truth" would be established engineering standards (like ASTM F2083, ASTM F1223) or validated internal test methods, and the performance of the predicate devices. The aim is to show the new device meets these engineering benchmarks or performs comparably to the predicates.

8. The sample size for the training set

  • Not applicable. There is no "training set" as this is not an AI/ML device.

9. How the ground truth for the training set was established

  • Not applicable. There is no "training set" for this device.

Conclusion from document:

The Persona Partial Knee System gained 510(k) clearance (K161592) based on demonstrating substantial equivalence to existing legally marketed predicate devices. This was achieved through:

  • Similar intended use (limited to medial tibiofemoral compartment, cemented use).
  • Use of similar materials (Co-Cr-Mo alloy for femoral, Ti-6Al-4V alloy for tibial, Vivacit-E Vitamin E Highly Crosslinked Polyethylene for articular surfaces), which are already used in predicate/reference devices.
  • Similar design features.
  • Similar sterilization methods.
  • Non-clinical mechanical tests and engineering analyses that showed the device performed comparably or acceptably against established engineering standards and predicate device performance. The specific quantitative acceptance criteria for each test are not detailed in this summary document but would have been part of the full 510(k) submission.

§ 888.3520 Knee joint femorotibial metal/polymer non-constrained cemented prosthesis.

(a)
Identification. A knee joint femorotibial metal/polymer non-constrained cemented prosthesis is a device intended to be implanted to replace part of a knee joint. The device limits minimally (less than normal anatomic constraints) translation in one or more planes. It has no linkage across-the-joint. This generic type of device includes prostheses that have a femoral condylar resurfacing component or components made of alloys, such as cobalt-chromium-molybdenum, and a tibial component or components made of ultra-high molecular weight polyethylene and are intended for use with bone cement (§ 888.3027).(b)
Classification. Class II.