(35 days)
The Klassic Knee System is intended for prosthetic replacement in treatment of the following:
- · Patient conditions of non-inflammatory degenerative joint disease (NIDID): avascular necrosis and osteoarthritis
- Patient conditions of inflammatory joint disease (IJD): rheumatoid arthritis
- · Patients with failed previous surgery where pain, deformity, or dysfunction persists
- Correctable varus-valgus deformity and moderate flexion contracture
- · Revision of a previously failed knee arthroplasty
- · Patients who require a total knee replacement
The Klassic Knee System is indicated for cemented use only, except for the Klassic Femur with Cobalt 3D™, and the Klassic Tibial Baseplate with Ti-Coat®. which are indicated for cementless use.
The purpose of this 510(k) is to add size 5, 10mm Sombrero Patella components in Standard Poly and E-Link Poly to be used in conjunction with the Klassic® Knee System during total knee replacement. The components are manufactured from ultrahigh molecular weight polyethylene or Vitamin E blended ultrahigh molecular weight polyethylene with a 40mm diameter and 10mm thickness.
Here's a breakdown of the acceptance criteria and the study information based on the provided text, focusing on the product submitted in K190280:
The document (K190280) describes a 510(k) submission for new sizes of patella components (size 5, 10mm Sombrero Patella in Standard Poly and E-Link Poly) to be added to the existing Klassic® Knee System. The primary method of demonstrating substantial equivalence is through engineering analyses and comparison to predicate devices that are already cleared.
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria Category | Specific Criteria | Reported Device Performance |
|---|---|---|
| Conformance | Not explicitly detailed in the provided text as specific numerical criteria, but implied to be within acceptable limits for knee prosthetic components. | "The results of these analyses indicate that the subject Sombrero Patellae are substantially equivalent to the predicate Sombrero Patellae" in terms of conformance. This implies they meet the same or similar conformance standards as the previously cleared predicate devices (K150105 & K180159). |
| Contact Area | Not explicitly detailed in the provided text as specific numerical criteria, but implied to be within acceptable limits for knee prosthetic components to ensure proper articulation and wear characteristics. | "The results of these analyses indicate that the subject Sombrero Patellae are substantially equivalent to the predicate Sombrero Patellae" in terms of contact area. This implies they maintain appropriate contact area similar to the previously cleared predicate devices. |
| Contact Stress | Not explicitly detailed in the provided text as specific numerical criteria, but implied to be within acceptable limits to prevent material degradation and ensure longevity of the implant. | "The results of these analyses indicate that the subject Sombrero Patellae are substantially equivalent to the predicate Sombrero Patellae" in terms of contact stress. This suggests the contact stresses are within acceptable physiological and material limits, comparable to the predicate devices. |
| Mechanical Strength | Not explicitly detailed in the provided text as specific numerical criteria, but implied to be sufficient to withstand the physiological loads and stresses experienced in a knee joint over the expected lifespan of the implant. | "The results of these analyses indicate that the subject Sombrero Patellae are substantially equivalent to the predicate Sombrero Patellae" in terms of mechanical strength. This implies the new components possess adequate strength comparable to the predicate devices. |
| Peg Geometry | Not explicitly detailed in the provided text as specific numerical criteria, but implied to be consistent with the existing Klassic Knee System to ensure proper fixation and compatibility. | "The results of these analyses indicate that the subject Sombrero Patellae are substantially equivalent to the predicate Sombrero Patellae" in terms of peg geometry. This ensures the pegs are properly sized and shaped for intended use and fixation within the larger Klassic Knee System. |
| LAL Testing | Compliance with LAL (Limulus Amebocyte Lysate) testing requirements for orthopedic implants, typically to ensure absence of endotoxins. The specific acceptance criteria for LAL are standardized but not detailed here. | The subject components are in "compliance with LAL testing requirements for orthopedic implants." This indicates they passed the standard LAL test, demonstrating a safe level of endotoxins. |
2. Sample Size Used for the Test Set and Data Provenance
The provided text does not describe a clinical study with a "test set" in the traditional sense of patient data. Instead, it relies on engineering analyses and comparison to predicate devices. Therefore:
- Sample Size for Test Set: Not applicable as it's not a clinical study with patient data. The "test set" would be the specific physical components (size 5, 10mm Sombrero Patellae) that were subjected to the engineering analyses. The number tested is not specified but would typically be one or more samples per analysis to ensure consistency.
- Data Provenance: Not applicable as it's engineering analysis, not patient data from a specific country or collected retrospectively/prospectively. The analyses are performed on the device itself.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
- Number of Experts: Not applicable. For engineering analyses, "ground truth" is established through engineering principles, material science, and regulatory standards, not by expert consensus on clinical images or outcomes.
- Qualifications of Experts: The analyses would be performed by qualified engineers or technicians with expertise in biomaterials, biomechanics, and medical device testing, but this is not a ground truth establishment by clinical experts.
4. Adjudication Method for the Test Set
- Adjudication Method: Not applicable. There is no ambiguous patient data requiring adjudication. The results of the engineering analyses are typically objective measurements and calculations compared against established criteria or predicate device performance.
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, an MRMC comparative effectiveness study was not done. This is a medical device for knee replacement components, not an AI/imaging device.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Standalone Performance Study: No, this is not an AI/algorithm-driven device. It's a physical orthopedic implant.
7. The Type of Ground Truth Used (expert consensus, pathology, outcomes data, etc.)
- Type of Ground Truth: The "ground truth" in this context refers to the established performance characteristics and safety profile of the predicate devices (size 1-4 Sombrero Patellae, K150105 & K180159), as well as established engineering and material science principles and regulatory standards for orthopedic implants. The new device components are deemed substantially equivalent if they meet these established engineering performance benchmarks or demonstrate comparable performance to the predicates.
8. The Sample Size for the Training Set
- Sample Size for Training Set: Not applicable. This is not a machine learning or AI device that requires a "training set."
9. How the Ground Truth for the Training Set was Established
- Ground Truth for Training Set: Not applicable.
§ 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.