(204 days)
The Restoris® Porous Partial Knee System components are intended for unicompartmental knee arthroplasty to treat one or more of the following conditions:
- . Moderately disabling joint disease of the knee resulting from painful osteo- or post traumatic arthritis.
- . Revision of previous unsuccessful surgical procedures, either involving, or not involving, previous use of a unicompartmental knee prosthesis.
- . As an alternative to tibial osteotomy in patients with unicompartmental osteoarthritis.
The Restoris® Porous Femoral Component and PST Tibial Baseplate are intended for cementless or cemented fixation. The Tibial Baseplate may be used in conjunction with ancillary screw fixation. The porous surfaces of both the femoral and tibial tray components provide biological fixation when used in a cementless application.
The Restoris® Porous Partial Knee System is a unicompartmental knee system that includes porous coated, cast CoCr, asymmetric femoral components in sizes 1 – 8; and Ti6Al4V, asymmetric, porous tibial baseplate components in sizes 1 - 8. The subject femoral and tibial baseplate components are compatible and are intended for use with predicate MAKO Restoris MCK Tibial Onlay Inserts in standard UHMWPE or highly crosslinked vitamin E UHMWPE (K090763, K133039). The sagittal articular surface of the femoral condyle has an extended posterior radius that accommodates flexion up to 155%.
The provided text is a 510(k) summary for the Restoris® Porous Partial Knee System, which is a medical device. This type of submission focuses on demonstrating substantial equivalence to a predicate device rather than conducting a de novo study to establish new performance criteria. Therefore, the information you're requesting regarding "acceptance criteria and the study that proves the device meets the acceptance criteria" in the context of AI device evaluation metrics (like sensitivity, specificity, etc.) is not present in this document.
This document describes a traditional medical device (a knee implant), not an AI/ML diagnostic or predictive device. The "performance testing" mentioned refers to mechanical and material testing to ensure structural integrity and functional similarity to existing devices.
However, I can extract information related to the device's performance testing and how it relates to demonstrating substantial equivalence, which is the regulatory standard for this type of device.
Here's a breakdown of what is available in the document, framed as closely as possible to your request, but acknowledging the difference in device type:
1. Table of Acceptance Criteria and Reported Device Performance:
For a traditional medical device like a knee implant, "acceptance criteria" are not reported as statistical metrics like sensitivity or specificity. Instead, the "acceptance criteria" are implied by demonstrating that the device performs equivalently or acceptably in terms of mechanical strength, material compatibility, and design features compared to predicate devices. The "reported device performance" refers to the results of these engineering tests.
| Performance Metric (Implied Acceptance Criteria: Substantial Equivalence to Predicate) | Reported Device Performance (Summary of Testing) |
|---|---|
| Mechanical Performance: | |
| Femoral Component Fatigue | Tested; capable of withstanding expected in vivo loading. |
| Tibial Baseplate Fatigue | Tested; capable of withstanding expected in vivo loading. |
| Tibial Insert/Baseplate Locking Mechanism Strength | Previously tested (K090763 or K133039); capable of withstanding expected in vivo loading. |
| Femorotibial Congruency | Previously tested (K090763 or K133039); demonstrated substantial equivalence. |
| Femorotibial Contact Area | Previously tested (K090763 or K133039); demonstrated substantial equivalence. |
| Range of Motion | Previously tested (K090763 or K133039); demonstrated substantial equivalence. |
| Material/Design Characteristics: | |
| Porous Surface Characterization (Femoral and Tibial Baseplate) | Tested; shown equivalent to predicate device porous coatings. |
| Indications for Use | Same as one or more predicate knee systems. |
| Materials | Same as one or more predicate knee systems. |
| Design Features | Similar to one or more predicate knee systems. |
Explanation of "Acceptance Criteria" for this device: The primary "acceptance criterion" for a 510(k) submission is Substantial Equivalence (SE) to a legally marketed predicate device. This means the new device must have the same intended use and the same technological characteristics as the predicate, or, if it has different technological characteristics, these differences must not raise new questions of safety and effectiveness, and the device must be as safe and effective as the predicate. The performance testing outlined above is designed to demonstrate this substantial equivalence, primarily through mechanical testing and material characterization.
The following points are typically relevant for AI/ML device evaluations and are not applicable to this 510(k) summary for a traditional knee implant. I will explicitly state "Not Applicable" where the information is not provided because it pertains to a different type of device or study.
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 document does not describe a clinical study with a "test set" in the context of AI/ML data. The "testing" refers to benchtop mechanical and material characterization. "Data provenance" such as country of origin or retrospective/prospective is not relevant for this type of engineering performance testing.
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. There is no "ground truth" establishment by medical experts for a "test set" described in this submission. The "truth" for engineering tests is based on established standards, mechanical properties, and comparison to predicate device performance.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- Not Applicable. No expert adjudication method is described.
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 not an AI-assisted device. No MRMC study was conducted.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Not Applicable. This is a physical orthopedic implant, not an algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- Not Applicable. "Ground truth" in the AI/ML sense is not relevant here. The "truth" for the engineering performance tests is adherence to engineering standards and demonstration of comparable mechanical performance to predicate devices.
8. The sample size for the training set:
- Not Applicable. This is not an AI/ML device, so there is no training set.
9. How the ground truth for the training set was established:
- Not Applicable. No training set is involved.
In summary: The provided document is a regulatory submission (510(k)) for a traditional medical device (a knee implant), focusing on demonstrating substantial equivalence to already marketed devices. It details engineering performance testing (fatigue, material characterization) to ensure the device's physical and mechanical properties are comparable to its predicates, thereby establishing its safety and effectiveness. The questions you've posed are highly specific to the evaluation of AI/ML medical devices, which operate under a different set of performance and validation criteria.
§ 888.3535 Knee joint femorotibial (uni-compartmental) metal/polymer porous-coated uncemented prosthesis.
(a)
Identification. A knee joint femorotibial (uni-compartmental) metal/polymer porous-coated uncemented prosthesis is a device intended to be implanted to replace part of a knee joint. The device limits translation and rotation in one or more planes via the geometry of its articulating surface. It has no linkage across-the-joint. This generic type of device is designed to achieve biological fixation to bone without the use of bone cement. This identification includes fixed-bearing knee prostheses where the ultra-high molecular weight polyethylene tibial bearing is rigidly secured to the metal tibial baseplate.(b)
Classification. Class II (special controls). The special control is FDA's guidance: “Class II Special Controls Guidance Document: Knee Joint Patellofemorotibial and Femorotibial Metal/Polymer Porous-Coated Uncemented Prostheses; Guidance for Industry and FDA.” See § 888.1 for the availability of this guidance.