(87 days)
The Initia Knee System is intended for use in total knee arthroplasty for the following indications:
-
Painful and disabled knee joint resulting from osteoarthritis, traumatic arthritis where one or more compartments are involved.
-
Correction of varus, valgus, or posttraumatic deformity.
-
Correction or revision of unsuccessful osteotomy, arthrodesis, or failure of previous joint replacement procedure.
This device is for cemented use only.
The Kyocera Medical Technologies, Inc. (KMTI) Initia Knee System is a patellofemorotibial polymer/ metal/polymer semi-constrained prosthesis intended to replace a knee joint. The system consists of femoral, tibial and patella components intended for use with bone cement. The Initia Knee System includes both posterior-stabilizing (PS) and cruciate-retaining (CR) designs.
This document is a 510(k) summary for the Kyocera Medical Technologies, Inc. (KMTI) Initia Knee System. It details the device, its intended use, and its substantial equivalence to a predicate device, the KMTI A200 Knee System.
Here's the breakdown of the acceptance criteria and study information:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly present a table of "acceptance criteria" with specific pass/fail values. Instead, it lists various non-clinical performance tests that were conducted and states that the results were "acceptable." The implication is that the performance of the Initia Knee System met the requirements established for these tests, likely aligned with the standards cited.
| Performance Test / Acceptance Criteria Category | Reported Device Performance (Implied) |
|---|---|
| Tibial Post Fatigue Strength (static and fatigue) | Acceptable |
| Tibial Tray Locking Mechanism | Acceptable |
| Tibial-Femoral Constraint | Acceptable |
| Tibial-Femoral Contact Area/Contact Stress | Acceptable |
| Femoral Fatigue | Acceptable |
| Patello-Femoral Lateral Subluxation and Contact Area/Contact Stress | Acceptable |
| Compliance with Consensus Standards (listed below) | Compliant |
| Functional Equivalence to Predicate Device | Demonstrated Substantial Equivalence |
2. Sample Size Used for the Test Set and the Data Provenance
- Sample Size: The document does not specify the exact sample sizes used for each individual non-clinical performance test. It mentions "components" and "trials" which implies multiple units were tested per category.
- Data Provenance: The data is generated from non-clinical performance tests conducted by Kyocera Medical Technologies, Inc. ("KMTI"). The provenance is therefore internal testing by the manufacturer. The document does not specify the country of origin of the data beyond the manufacturer's location in Redlands, CA, USA. The data is prospective in the sense that these tests were conducted specifically for this 510(k) submission to demonstrate device performance.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts
This section is not applicable as the document describes non-clinical performance testing for a medical device (knee prosthesis), not an AI/software device that requires expert-established ground truth for a test set. The "ground truth" for these tests are the established engineering principles, material science properties, and consensus standards (e.g., ASTM, ISO) that define acceptable performance for orthopedic implants.
4. Adjudication Method for the Test Set
This section is not applicable for the same reasons as point 3. Performance is evaluated against objective engineering criteria and consensus standards, not through expert adjudication of subjective interpretations.
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
This section is not applicable. The subject device is a physical knee prosthesis, not an AI or software-based diagnostic or assistive tool. Therefore, a MRMC study involving human readers and AI assistance would not be relevant.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
This section is not applicable. The subject device is a physical knee prosthesis, not an algorithm or software. No standalone algorithm performance was assessed for this device.
7. The Type of Ground Truth Used
For the non-clinical performance tests, the "ground truth" is based on:
- Established engineering principles and biomechanical requirements: These tests assess the physical and mechanical properties of the device.
- Consensus standards: The document explicitly lists numerous ASTM and ISO standards (e.g., ASTM F1672-14 for patellar prosthesis, ASTM F1800-12 for tibial tray fatigue, ISO 7207-2 for articulating surfaces). These standards define test methodologies and acceptable performance metrics, which serve as the "ground truth" for assessing device safety and effectiveness.
- Comparison to predicate device: The fundamental basis of a 510(k) submission is to demonstrate "substantial equivalence" to a legally marketed predicate device. Therefore, the predicate's known safe and effective performance also acts as a reference for the "ground truth" of what is considered acceptable.
8. The Sample Size for the Training Set
This section is not applicable. The subject device is a physical knee prosthesis. There is no concept of a "training set" as there would be for an AI/machine learning model. The design and manufacturing process are informed by established engineering knowledge and previous experience with similar devices.
9. How the Ground Truth for the Training Set Was Established
This section is not applicable for the same reasons as point 8.
§ 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.