(223 days)
The patient should be skeletally mature to receive a knee replacement. Patients should have adequate bone stock and size to support and accept the prosthesis.
The patient's need for knee replacement should be due to one or more of the following conditions:
- Non-inflammatory degenerative joint disease including osteoarthritis, traumatic arthritis, or avascular necrosis.
- Inflammatory degenerative joint disease including rheumatoid arthritis.
- Functional deformity such as varus, valgus or flexion deformities.
- Revision procedures where other treatments or devices have failed.
- Fractures that are unmanageable using other techniques.
The Active-X Knee replacement system is indicated for cemented fixation with bone cement (PMMA) only.
The Active-X Knee system is a modular knee system consisting of a femoral component, a standard, ultracongruent and ultracongruent+ meniscal insert (anterior lip), a patella and a tibial baseplate. The femoral component and tibial baseplate components are manufactured from cast cobalt chromium alloy and are intended for use with bone cement. All variants of the meniscal insert and patella are manufactured from UHMWPE.
This document, K160159, describes the Active-X Total Knee System, a knee replacement device. The regulatory submission primarily relies on demonstrating substantial equivalence to predicate devices through engineering evaluations rather than extensive new performance testing.
Here's an analysis of the acceptance criteria and study information provided:
1. Table of Acceptance Criteria and the Reported Device Performance:
The document does not explicitly state acceptance criteria in a quantitative format typical of a performance study. Instead, the "Performance Testing" section states that engineering evaluations were performed to demonstrate equivalent performance between the Active-X Knee System and the predicate device (dj Orthopedics Alaron Surgical Active Knee® System (K021740)).
The approach taken is that if the new components (ultracongruent+ meniscal insert and inlay patella) perform equivalently to existing similar components, then further testing is not required.
| Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|
| Equivalence in Range of Motion | Engineering evaluations showed the ultracongruent+ meniscal insert and inlay patella perform equivalently to the remainder of the Active-X Knee System and the predicate (dj Orthopaedics Alaron Surgical Active Knee System K021740). Therefore, further range of motion analysis was not required. |
| Equivalence in Modular Component Connection Strength | Engineering evaluations showed the ultracongruent+ meniscal insert and inlay patella perform equivalently to the remainder of the Active-X Knee System and the predicate. Therefore, further modular component connection strength testing was not required. |
| Equivalence in Component Contact Area and Stress | Engineering evaluations showed the ultracongruent+ meniscal insert and inlay patella perform equivalently to the remainder of the Active-X Knee System and the predicate. Therefore, further component contact area and stress testing was not required. |
| Equivalence in Component Constraint | Engineering evaluations showed the ultracongruent+ meniscal insert and inlay patella perform equivalently to the remainder of the Active-X Knee System and the predicate. Therefore, further component constraint testing was not required. |
| Equivalence in Wear Characteristics | Engineering evaluations showed the ultracongruent+ meniscal insert and inlay patella perform equivalently to the remainder of the Active-X Knee System and the predicate. Therefore, further wear testing was not required. |
| Equivalence in Cement Fixation | Engineering evaluations showed the ultracongruent+ meniscal insert and inlay patella perform equivalently to the remainder of the Active-X Knee System and the predicate. Therefore, further cement fixation testing was not required. |
| Overall Substantial Equivalence to Predicate Devices (K021740, K032683) | Claimed: The Active-X Knee System has the same intended use, indications for use, materials, and design as the Alaron Surgical Active Knee® System (K021740), with the ultracongruent+ meniscal insert having an increased anterior lip and the inlay patella having similar design features to the Genesis II Total Knee System Inlay Patella Component (K032683). Non-clinical testing results (engineering evaluations) support this claim. |
2. Sample size used for the test set and the data provenance:
- Sample size for test set: Not applicable (N/A). The document indicates that extensive physical testing for performance was "omitted" based on engineering evaluations. It refers to "engineering evaluations" rather than a clinical or biomechanical test set with a specific sample size.
- Data provenance: Not explicitly stated, as no new primary performance testing data (e.g., from a test set of devices) is presented. The "engineering evaluations" would likely be laboratory-based analyses and comparisons to existing predicate device data.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Number of experts: N/A. No external experts or ground truth establishment process for a test set is described. The "engineering evaluations" would have been conducted by the manufacturer's engineers.
- Qualifications of experts: N/A.
4. Adjudication method for the test set:
- Adjudication method: N/A. No adjudication method is mentioned as there was no test set requiring such a process.
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:
- N/A. This device is a knee replacement system, not an AI-assisted diagnostic or imaging device. Therefore, an MRMC study is not relevant.
6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
- N/A. This is a physical medical device (knee implant), not an algorithm or software.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- Type of ground truth: N/A for new performance testing. The "ground truth" for the substantial equivalence claim is based on the established performance and safety profiles of the legally marketed predicate devices (dj Orthopedics Alaron Surgical Active Knee® System K021740 and Smith & Nephew Genesis II Knee System Inlay Patella Component K032683). The engineering evaluations aimed to show that the new components would perform comparably to these established devices.
8. The sample size for the training set:
- N/A. This is a physical medical device, not a machine learning model.
9. How the ground truth for the training set was established:
- N/A. This is a physical medical device, not a machine learning model.
§ 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.