(79 days)
The Natural-Knee II - Unicompartmental Knee Prosthesis is intended for resurfacing of one side of the knee joint.
The Natural-Knee II - Unicompartmental Knee Prosthesis is intended for resurfacing of one side of the knee joint. The system consists of metallic femoral and tibial components as well as a polyethylene tibial insert. The femoral component is a symmetrically designed component, eliminating the need for left/right orientations. The femoral component is manufactured from cast cobalt chromium/molybdenum (CoCrMo) and features a central cruciate stem which aids in stabilization. A central posterior runner is incorporated into the inner surface to provide further rotational stability. Contact area is maximized by the "sweeping" condylar geometry. Both a nonporous and CSTi porous coated version are available. The femoral component is available in 7 sizes (1-7). The tibial component is a symmetrically designed component, eliminating the need for left/right orientations. The tibial component is manufactured from wrought titanium alloy (Ti-6AI-4V). The baseplate features three pegs on the underside which aid in rotational stabilization. A screw hole has been placed in the center of the baseplate for optional screw fixation. The baseplate is designed with capture features which permit the UHMWPE tibial insert to be snapped into place. Both a nonporous and CSTi porous coated version are available. The baseplate is available in 6 sizes (1-6). The tibial insert is a symmetrically designed component manufactured from Ultra-High Molecular Weight Polyethylene (ASTM F648). The insert articulating geometry is semiconstrained and is captured in the baseplate by the mating capture features. The insert is available in 3 thicknesses (9, 11, and 13 mm) and 3 sizes (1-2, 3-4, and 5-6).
The provided document is a 510(k) summary for the Natural-Knee® II - Unicompartmental Knee System, a medical device. This summary describes the device and its intended use, but it does not contain information about acceptance criteria or a study proving that the device meets specific performance metrics in the way that an AI/software device submission would.
The document states that the device is comparable to other legally marketed devices based on certain tests, which is a common approach for demonstrating substantial equivalence in 510(k) submissions for conventional medical devices. However, it does not specify acceptance criteria as quantitative thresholds for performance (e.g., sensitivity, specificity, accuracy) nor does it detail a clinical study with a test set, ground truth experts, or statistical analyses of device performance.
Therefore, I cannot fill out the requested table or additional information points as they are designed for evaluating AI/software performance studies, which are not present in this document.
Here's how I would interpret the information provided in the context of your request, noting the absence of AI/software-specific details:
Acceptance Criteria and Device Performance (as inferred from comparability statements)
| Acceptance Criteria (Inferred) | Reported Device Performance (Inferred) |
|---|---|
| Performance of Contact Area and Constraint (Comparable to existing legally marketed devices) | Demonstrated to be comparable to other legally marketed devices. |
| Push-out Strength of Baseplate-Insert Locking Mechanism (Comparable to existing legally marketed devices) | Demonstrated to be comparable to other legally marketed devices. |
| Overall Similarity to Predicate Devices: | The Natural-Knee II Unicompartmental Knee Prosthesis is similar to the Howmedica PCA Unicompartmental Knee System, the DePuv Synatomic Unicondylar Knee, the Wright Medical Whiteside Ortholoc II Unicondylar Knee System, the Osteonics Omnifit SCR Knee System, the Zimmer Miller/Galante Unicompartmental Knee System, the Kirschner Performance Unicompartmental Knee, the Smith & Nephew Richards Genesis Unicompartmental Knee, and the Johnson & Johnson PFC Unicompartmental Knee System. |
1. Sample sizes used for the test set and the data provenance:
- Sample Size (Test Set): Not specified. The document refers to "testing," but does not provide numbers of components or instances tested.
- Data Provenance: Not specified (e.g., country of origin, retrospective/prospective). It likely refers to in-house or third-party engineering/bench testing.
2. 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):
- Number of Experts: Not applicable. This is not a study involving expert interpretation or clinical ground truth in the context of an AI/software device. The "ground truth" here is the performance under bench testing conditions.
- Qualifications of Experts: Not applicable.
3. Adjudication method (e.g., 2+1, 3+1, none) for the test set:
- Adjudication Method: Not applicable.
4. 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 physical medical device, not an AI/software product requiring an MRMC study.
- Effect Size of Human Readers with/without AI: Not applicable.
5. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Standalone Performance: Not applicable. This is a physical medical device.
6. The type of ground truth used (expert consensus, pathology, outcomes data, etc):
- Type of Ground Truth: For the "testing" mentioned, the ground truth would be physical measurements and engineering assessments (e.g., force required for push-out, contact area measurements) under controlled laboratory conditions, compared against established standards or performance of predicate devices.
7. The sample size for the training set:
- Training Set Sample Size: Not applicable. This is not an AI/machine learning device that uses a training set. The design of the device would have involved engineering principles and potentially iterations, but not "training data" in the AI sense.
8. How the ground truth for the training set was established:
- Ground Truth for Training Set: Not applicable.
§ 888.3530 Knee joint femorotibial metal/polymer semi-constrained cemented prosthesis.
(a)
Identification. A knee joint femorotibial metal/polymer semi-constrained cemented 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 surfaces. It has no linkage across-the-joint. This generic type of device includes prostheses that consist of a femoral component made of alloys, such as cobalt-chromium-molybdenum, and a tibial component made of ultra-high molecular weight polyethylene and is limited to those prostheses intended for use with bone cement (§ 888.3027).(b)
Classification. Class II.