(54 days)
The RT-PLUS Knee System is a tricompartmental rotating hinged prosthesis o the total condylar type. The system consists of femoral, tibial and patellar components. It is indicated for use for replacement of the total knee joint in which significant bone loss and/or ligamentous deficiencies have occurred due to tumors, trauma, infections, revision or connective tissue disorders. RT-PLUS Modular Knee provides joint stability when any or all of the following structures are non-functional: MCL, LCL, PCL, ACL or the illiotibial band.
The RT-PLUS Knee and RT-PLUS Modular Knee are hinged tri-compartmental prostheses with femoral, tibial, and patella components and are of the cemented total condylar type. They are intended to be used for replacement of the total knee ioint in which significant bone loss and/or ligamentous deficiencies have occurred due to tumors, trauma, infections, revision or connective tissue disorders. Both of these knee systems provide joint stability when any or all of the following structures are non-functional: MCL, LCL, PCL, ACL or the illiotibial band. Both systems include polyethylene tibial augmentation blocks. The Modular knee includes modular femoral and tibial stems.
The modifications described in this submission include:
- Changes to the outside surfaces of the ultra high molecular weight polyethylene (ASTM F648) 1. augmentation blocks and addition of blocks for Size 2 and 10 tibial baseplates. (Original cleared on K003504)
- Additional titanium alloy (ASTM F136) stem sizes (Original cleared on K003504) 2.
- Addition of CoCrMo (ASTM F75) augmentation blocks 3.
- Changes to femoral and tibial baseplate components to accept CoCrMo blocks (Original cleared on 4. K003504)
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- Addition of size 2 and 10 femoral and tibial baseplate components (Non-modular cleared on K013340)
This 510(k) summary describes modifications to an existing knee implant device, not a new AI/ML-powered device. Therefore, the questions related to AI/ML device performance, ground truth, expert adjudication, and sample sizes for training/testing are not applicable because the provided text is about a traditional medical device (a knee prosthesis).
However, I can still extract information about the acceptance criteria and the study conducted for this traditional medical device as described in the provided document.
Acceptance Criteria and Study for RT-PLUS and RT-PLUS Modular Knee Systems
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Standard / Test) | Reported Device Performance / Compliance |
|---|---|
| ISO 14789-1: "Implants for surgery -- Total knee-joint prostheses -- Part 1: Determination of endurance properties of knee tibial trays" | Complied with (as stated in "Summary Nonclinical Tests") |
Explanation of the Acceptance Criteria (ISO 14789-1):
This international standard specifies methods for determining the endurance properties of knee tibial trays. This typically involves fatigue testing to assess the strength and durability of the tibial component under simulated physiological loads over a large number of cycles to ensure it can withstand the forces experienced in the human body over its intended lifespan without failure.
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: Not specified in the provided document. The standard ISO 14789-1 generally requires testing multiple samples to demonstrate compliance, but the exact number for this submission is not given.
- Data Provenance: Not applicable in the context of clinical data for AI/ML. The "data" here refers to the results of mechanical non-clinical testing performed on the device components. This testing would have been conducted in a laboratory setting by the manufacturer or a contracted testing facility.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications of Experts
Not applicable. This is not an AI/ML device where expert ground truth is established for a test set. The "ground truth" for a mechanical test like ISO 14789-1 is the physical failure or endurance of the device under specified test conditions, observed directly by engineers/technicians.
4. Adjudication Method for the Test Set
Not applicable. There is no adjudication method in the context of mechanical endurance testing. The results are objective measurements against the standard's requirements.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and Effect Size
Not applicable. This is not an AI/ML device, and no MRMC study would be conducted for a knee prosthesis.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Study Was Done
Not applicable. This is not an AI/ML device.
7. The Type of Ground Truth Used
The "ground truth" for this device's performance is established by the physical performance of the device components during mechanical testing according to the ISO 14789-1 standard. This involves objective measurements of endurance, fatigue, and structural integrity under simulated conditions.
8. The Sample Size for the Training Set
Not applicable. This is not an AI/ML device that requires a training set.
9. How the Ground Truth for the Training Set Was Established
Not applicable. This is not an AI/ML device that requires a training set.
Summary of the Device and Submission:
The submission describes modifications to existing RT-PLUS and RT-PLUS Modular Knee Systems. The modifications primarily involve changes to materials, sizes, and components (e.g., augmentation blocks, stem sizes). The claim for substantial equivalence is based on the devices having the "same indications, materials and fundamental scientific technology" as the previously cleared predicate devices. The non-clinical testing performed to support the modifications and substantial equivalence claim involved compliance with ISO 14789-1 for "endurance properties of knee tibial trays." This indicates that the mechanical integrity and durability of the updated tibial components were assessed according to established industry standards.
§ 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.