(118 days)
This device is indicated for patients with severe knee pain and disability due to:
- Rheumatoid arthritis, osteoarthritis, traumatic arthritis, polyarthritis.
- Collagen disorders, and/or avascular necrosis of the femoral condyle.
- Post-traumatic loss of joint configuration, particularly when there is patellofemoral erosion, dysfunction or prior patellectomy
- Moderate valgus, varus, or flexion deformities.
- The salvage of previously failed surgical attempts or for a knee in which satisfactory stability in flexion cannot be obtained at the time of surgery.
This device is intended for cemented use only.
The NexGen MIS Tibial Components are part of the NexGen system of semiconstrained, nonlinked condylar knee prostheses.
Here's an analysis of the provided FDA 510(k) summary, focusing on the absence of specific acceptance criteria and detailed study information, as is often the case with predicate device submissions.
Acceptance Criteria and Device Performance:
| Acceptance Criteria Category | Specific Acceptance Criteria | Reported Device Performance |
|---|---|---|
| Mechanical Performance | Not explicitly stated in the provided document (e.g., specific fatigue limits, wear rates, tensile strength, etc.) | "Performance testing completed as part of the design assurance process demonstrated that this device is safe and effective and substantially equivalent to the predicate device." |
| Biocompatibility | Not explicitly stated (implied to be met through material equivalence to predicate) | Not explicitly detailed, but implied to be equivalent to predicate due to "same materials and processes." |
| Sterilization | Not explicitly stated (implied to be met through equivalence to predicate) | "The device is packaged and sterilized using the same materials and processes." |
| Material Properties | Not explicitly stated (implied to be met through equivalence to predicate) | "same materials and processes" as predicate devices. |
| Clinical Efficacy/Safety | Not applicable; no clinical acceptance criteria were required. | "Clinical data and conclusions were not needed for this device." |
Explanation: This 510(k) submission for the NexGen® Complete Knee Solution MIS™ Tibial Components relies on substantial equivalence to previously cleared predicate devices (K933785, K991581, K031061). In such cases, detailed, de novo acceptance criteria and performance metrics are typically not provided as they would be for a new device. Instead, the device is deemed acceptable if it can demonstrate equivalent safety and effectiveness to legally marketed predicate devices, usually through non-clinical performance testing that confirms the modifications do not alter the fundamental scientific technology or intended use. The document explicitly states that clinical data was not needed.
Study Information (Based on the Provided Document):
This submission does not describe a clinical study comparing the device to a set acceptance criterion, but rather relies on non-clinical performance testing and substantial equivalence to predicate devices. Therefore, many of the requested categories are not applicable or cannot be determined from the provided text.
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Sample Size Used for the Test Set and Data Provenance:
- Test Set Sample Size: Not applicable for a clinical study, as "Clinical data and conclusions were not needed for this device." For non-clinical performance testing, the sample sizes for mechanical tests (e.g., fatigue, static strength) are not specified in this summary.
- Data Provenance: Not applicable for a clinical study. For non-clinical testing, it would be internal laboratory data generated by Zimmer, Inc.
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Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications:
- Not applicable as no clinical ground truth was established for this submission.
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Adjudication Method for the Test Set:
- Not applicable as no clinical ground truth was established for this submission.
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Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
- No, an MRMC comparative effectiveness study was not done. The document explicitly states, "Clinical data and conclusions were not needed for this device."
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Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study:
- Not applicable. This device is a physical knee prosthesis component, not an algorithm or AI-driven system.
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Type of Ground Truth Used:
- Not applicable for clinical ground truth. For non-clinical testing, the "ground truth" would be established engineering specifications and accepted testing standards for mechanical performance of knee implants.
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Sample Size for the Training Set:
- Not applicable. This device is a physical knee prosthesis component, not an AI/algorithm-driven system requiring a training set.
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How the Ground Truth for the Training Set Was Established:
- Not applicable. This device is a physical knee prosthesis component, not an AI/algorithm-driven system requiring a training set.
Conclusion from the Document:
The FDA clearing document (K043101) indicates that the device's safety and effectiveness were demonstrated through non-clinical performance testing and by establishing substantial equivalence to predicate devices. The modifications made to the NexGen MIS Tibial Components were considered "minor" and "do not change the intended use or the fundamental scientific technology." Therefore, detailed clinical studies, specific acceptance criteria in the clinical sense, or sophisticated ground truth establishment methods were not required for this 510(k) clearance.
§ 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.