RT-PLUS KNEE ADDITIONAL COMPONENTS by PLUS ORTHOPEDICS

The RT-PLUS™ Knee System is a tri-compartmental rotating hinged prosthesis of the total condylar type. The system consists of femoral, tibial and patellar components. It is indicated for use as a replacement of the knee joint in which significant bone loss and/or ligamentous deficiencies have occurred due to tumors, trauma, infection, revision or connective tissue disorders. The RT-PLUS™ Modular Cemented Knee provides joint stability when any or all of the following structures are non-functional: MCL, LCL, PCL, ACL and the iliotibial band.

Device Description

The RT-PLUS™ Additional Knee Components are identical to the predicate device, except sizes 2 and 10 were added to the existing sizes 4, 6, and 8 of the RT-PLUS™ Knee System.

AI/ML Overview

This 510(k) submission describes a device modification (addition of new sizes) to an existing knee replacement system, the RT-PLUS Knee System. It does not present a study with acceptance criteria and reported device performance in the way typically seen for AI/ML-based medical devices or devices where clinical performance metrics (like sensitivity, specificity, accuracy) are evaluated against a predefined threshold.

Instead, the submission focuses on mechanical performance and substantial equivalence to a predicate device for a mechanical implant.

Here's a breakdown based on the provided document, addressing your questions where applicable, and noting where information is not available due to the nature of the submission:

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria (Not explicitly stated as such, but inferred from the document)	Reported Device Performance
Biomechanical Fatigue Tests: Favorable comparison to predicate device for worst-case model.	"The test results of the additional components were favorable to the predicate device and are sufficient for in vivo loading."
Substantial Equivalence: Device modification (additional sizes) does not raise new questions of safety or effectiveness and is equivalent to the legally marketed predicate device.	The FDA letter confirms "substantial equivalence" to legally marketed predicate devices for the stated indications for use.

2. Sample size used for the test set and the data provenance

Test Set (for biomechanical fatigue tests): Not specified beyond "worst-case model." This typically refers to particular configurations or dimensions of the prosthetic components selected to represent the highest stress conditions. It's a physical test, not a data-driven clinical study.
Data Provenance: Not applicable in the context of clinical data. The tests are biomechanical laboratory tests.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts

Ground Truth Establishment: Not applicable. Biomechanical tests use engineering principles and standardized testing methodologies. There isn't "ground truth" derived from expert consensus in this type of study.

4. Adjudication method for the test set

Adjudication Method: Not applicable. Biomechanical tests have objective, measurable outcomes (e.g., cycles to failure, stress levels).

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

MRMC Study: No. This is a submission for a mechanical implant, not an AI/ML diagnostic or assistive device.

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

Standalone Performance: No. This is a mechanical implant, not an algorithm.

7. The type of ground truth used

Ground Truth: For biomechanical fatigue tests, the "ground truth" is based on established engineering standards and methodologies for material and device performance under simulated physiological loading. There is no expert consensus, pathology, or outcomes data used as ground truth for these specific tests.

8. The sample size for the training set

Training Set: Not applicable. This is not an AI/ML device.

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

Training Set Ground Truth Establishment: Not applicable.

Summary of the document's relevance to your questions:

This 510(k) submission addresses the modification of an existing knee prosthesis by adding new sizes. The key performance data provided relates to biomechanical fatigue testing of the new components, confirming they meet performance expectations comparative to the predicate device and are "sufficient for in vivo loading." The FDA's review confirms substantial equivalence based on these tests and the device's design.

It's crucial to understand that this submission is for a traditional medical device (a mechanical implant), not for a software-as-a-medical-device (SaMD) or an AI/ML-based device. Therefore, many of your questions, particularly those related to clinical studies, human readers, AI performance metrics, and training data, are not relevant to this specific document or type of device.

Summary

{0}------------------------------------------------

SPECIAL 510(K) DEVICE MODIFICATION RT-PLUS Knee Additional Components October 5, 2001

DEC 2 0 2001

KD13340

510(k) Summary of Safety and Effectiveness 510(k) Summary of Safety and Effectiveness

[in accordance with SMDA of 1990, 21 CFR 807.92(c)]

PLUS ORTHOPEDICS Contact: 6055 Lusk Blvd. San Diego, CA 92121 Tel: 858-550-3800 x 2506 Attn: Mr. Hartmut Loch, RAC Director, Regulatory Affairs
RT-PLUS™ Knee System Trade name:

Hinged Knee Prosthesis Common name:

Prosthesis Knee, Femorotibial, Constrained, Cemented, Metal/Polymer Classification & 888.3510 - Class II name: Product Code: KRO - 87 Orthopedic Device Panel

RT-PLUS Knee System, S/E May 11, 2001 - K003504 manufactured by Predicate Device: PLUS Endoprothetik AG, Switzerland

The RT-PLUS™ Additional Knee Components are identical to the Device predicate device, except sizes 2 and 10 were added to the existing sizes Modification 4, 6, and 8 of the RT-PLUS™ Knee System. Description:

The RT-PLUS™ Knee System is a tri-compartmental rotating hinged Indications: prosthesis of the total condylar type. The system consists of femoral, tibial and patellar components. It is indicated for use as a replacement of the knee joint in which significant bone loss and/or ligamentous deficiencies have occurred due to tumors, trauma, infection, revision or connective tissue disorders. The RT-PLUS™ Modular Cemented Knee provides joint stability when any or all of the following structures are nonfunctional: MCL, LCL, PCL, ACL and the iliotibial band.

Contraindications include acute or chronic infections (local or systemic), Contraindications: serious lesions of muscles, nerves or blood vessels, which put the affected limb at risk, bony defects or poor bone quality, which might endanger the stability of the prosthesis, and any concurrent disease, which might interfere with the function of the implant.

Biomechanical fatigue tests have been performed on the worst-case Performance model. The test results of the additional components were favorable to data: the predicate device and are sufficient for in vivo loading.

{1}------------------------------------------------

Image /page/1/Picture/12 description: The image is a black and white logo for the U.S. Department of Health and Human Services. The logo features a circular border with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES • USA" around the edge. Inside the circle is a stylized image of three overlapping, curved shapes that resemble a bird in flight.

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

Mr. Hartmut Loch, RAC Director, Regulatory Affairs PLUS Orthopedics 6055 Lusk Boulevard San Diego, CA 92121-2700

DEC 2 0 2001

Re: K013340

Trade/Device Name: RT-PLUS" Hinged Knee Regulation Number: 21 CFR §888.3510 Regulation Name: Knee joint femorotibial metal/polymer constrained cemented prosthesis Regulatory Class: Class II Product Code: KRO Dated: November 16, 2001 Received: November 20, 2001

Dear Mr. Loch:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require with the providions of the approval application (PMA). You may, therefore, market the approval or a promance apple on and provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, provisions facturing practice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to such additional controls. Existing major regulations (I writ), it may be bactor be found in the Code of Federal Regulations, Title 21, Parts arround your addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does r lease on that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not I coderal agencies: "Foundsiveing (21 CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions

{2}------------------------------------------------

Page 2 – Mr. Hartmut Loch

This letter will allow you to begin marketing your device as described in your Section 510(k) I his letter will anow you to ocgin maxioning your antial equivalence of your device to a legally premarket notification. The IDA inding of subscribed on of a market of your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and if you desire specific advice for your dovice diagnostic devices), please contact the Office of additionally 21 CFC Part 807.10 for mi 120 c.m. 1120 c.m. 112 promotion and advertising of Compliance at (301) 394-6057. Tidnitionship to questions of (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). Other general information on your responsibilities under the Act may be obtained from the Division (800) Other general information on your respend and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address 036-2011 or (9) fda gov/cdrh/dsma/dsmamain.html

Sincerely yours,

Celia M. Witten, Ph.D., M.D.

Director Division of General, Restorative and Neurological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

{3}------------------------------------------------

SPECIAL 510(K) DEVICE MODIFICATION RT-PLUS Knee Additional Components October 5, 2001

Page 1

510(k) Number:

Device Name(s):

RT-PLUS Knee Additional Components

Indications for Use:

PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NECESSARY

Concurrence of CDRH, Office of Device Evaluation (ODE)

(Division Sign-Off)
Division of General, Restorative and Neurological Devices

510(k) Number	K013340
---------------	---------

Prescription Use	X	OR	Over-The-Counter-Use
(Per 21 CFR 801.109)			(Optional format 1-2-96)

Regulation Number and Section

§ 888.3510 Knee joint femorotibial metal/polymer constrained cemented prosthesis.

(a)
Identification. A knee joint femorotibial metal/polymer constrained cemented prosthesis is a device intended to be implanted to replace part of a knee joint. The device limits translation or rotation in one or more planes and has components that are linked together or affined. This generic type of device includes prostheses composed of a ball-and-socket joint located between a stemmed femoral and a stemmed tibial component and a runner and track joint between each pair of femoral and tibial condyles. The ball-and-socket joint is composed of a ball at the head of a column rising from the stemmed tibial component. The ball, the column, the tibial plateau, and the stem for fixation of the tibial component are made of an alloy, such as cobalt-chromium-molybdenum. The ball of the tibial component is held within the socket of the femoral component by the femoral component's flat outer surface. The flat outer surface of the tibial component abuts both a reciprocal flat surface within the cavity of the femoral component and flanges on the femoral component designed to prevent distal displacement. The stem of the femoral component is made of an alloy, such as cobalt-chromium-molybdenum, but the socket of the component is made of ultra-high molecular weight polyethylene. The femoral component has metallic runners which align with the ultra-high molecular weight polyethylene tracks that press-fit into the metallic tibial component. The generic class also includes devices whose upper and lower components are linked with a solid bolt passing through a journal bearing of greater radius, permitting some rotation in the transverse plane, a minimal arc of abduction/adduction. This generic type of device is limited to those prostheses intended for use with bone cement (§ 888.3027).(b)
Classification. Class II.