(40 days)
The ConforMIS Total Knee Repair System ("iTotal") is a minimally invasive, bone preserving primary total knee system intended 'for use in patients with severe knee joint pain and disability. The indications for use include restoring joint function and relief of pain due to:
Painful joint disease due to osteoarthritis, traumatic arthritis, rheumatoid arthritis of the knee
Post traumatic loss of joint function
Mild to moderate valgus or varus deformity of the knee
The ConforMIS Total Knee Repair System ("iTotal") is intended only for use with bone cement.
The additional 6.0 mm thickness option for the ConforMIS Total Knee Repair System tibial component is intended to provide the surgeon with an additional option for sizing the tibial component. The X/Y dimensions of the component (i.e. the two-dimensional shape or "footprint") are designed to conform to the patient's anatomy as closely as possible based on images (MRI or CT scan) of the patient's knee. It is available as an UHMEPE component with minimal thickness of 6.0 mm.
Acceptance Criteria and Device Performance for ConforMIS Total Knee Repair System (K080936)
This submission describes the ConforMIS Total Knee Repair System (iTotal): Tibial Component Extension of Size Range. The primary goal of the submission is to demonstrate substantial equivalence to previously cleared predicate devices.
1. Table of Acceptance Criteria and Reported Device Performance
The core of this 510(k) submission relies on demonstrating substantial equivalence to existing predicate devices. Therefore, the "acceptance criteria" are implicitly defined by the characteristics of these predicates, and the "reported device performance" is a direct comparison to those characteristics.
| Acceptance Criteria Category | Specific Criteria (Based on Predicate Devices) | Reported Device Performance (ConforMIS Total Knee Repair System Tibial Component 6.0mm) |
|---|---|---|
| Design Characteristics | Equivalent design and production process to ConforMIS Total Knee Repair System (K052687) in using imaging data for patient-matched geometry. | Equivalent in terms of design and production process. Uses imaging data to design patient-matched implant geometry. |
| Material Composition | Identical materials to ConforMIS Total Knee Repair System (K052687). | Uses identical materials. |
| Intended Use & Indications | Shares the same intended use and indications for use as the ConforMIS Total Knee Repair System (K052687) and other cited predicates. | Shares the same intended use and indications for use: "minimally invasive, bone preserving primary total knee system intended for use in patients with severe knee joint pain and disability due to osteoarthritis, traumatic arthritis, rheumatoid arthritis, post traumatic loss of joint function, and mild to moderate valgus or varus deformity of the knee." Explicitly for cemented use only. |
| Mechanical Safety/Function | Mechanical safety and function equivalent to cited predicate devices (e.g., ConforMIS Uni-compartmental "iUni", Bi-compartmental "iDuo"). | Testing completed as part of design verification found the device to be as safe and effective as predicate devices. The additional 6.0 mm thickness option provides an alternative sizing option. |
| Minimum Thickness | Absolute minimum thickness equivalent to tibial components cleared for use with ConforMIS uni-compartmental ("iUni") and bi-compartmental ("iDuo") devices. | "Substantially equivalent to the tibial components cleared for use with the ConforMIS uni-compartmental ('iUni') and bi-compartmental ('iDuo') Device in terms of absolute minimum thickness." Minimal thickness of 6.0 mm. |
| New Safety/Effectiveness Issues | No new safety or effectiveness issues raised compared to predicate devices. | "raises no new safety or effectiveness issues." |
2. Sample Size Used for the Test Set and Data Provenance
The submission does not refer to a "test set" or mention any clinical studies involving human subjects for this particular 510(k) submission (K080936). Instead, it relies on non-clinical performance testing for design verification and comparison to predicates.
- Sample Size for Test Set: Not applicable, as no clinical test set was used.
- Data Provenance: Not applicable for clinical data. Non-clinical performance data would be generated in a lab setting, likely within the US, by the manufacturer.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
Not applicable, as no clinical test set requiring expert ground truth establishment was conducted for this 510(k). The evaluation is based on mechanical testing and comparison to predicate device specifications and performance.
4. Adjudication Method for the Test Set
Not applicable, as no clinical test set requiring an adjudication method was conducted for this 510(k).
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done. This 510(k) focuses on a mechanical device (knee implant) and its design/material properties, not an imaging or diagnostic AI device that would typically involve MRMC studies.
6. Standalone (Algorithm Only Without Human-in-the-loop) Performance Study
No, a standalone performance study was not done. This device is a component of a knee replacement system; its "performance" is inherently linked to its surgical implantation and function within the human body, and its evaluation in this submission is through non-clinical testing and comparison to predicates.
7. Type of Ground Truth Used for the Test Set
Not applicable, as no clinical test set requiring ground truth was conducted for this 510(k). The "ground truth" for the non-clinical testing would be the engineering specifications and performance standards established for such devices, against which the new device's test results are compared.
8. Sample Size for the Training Set
Not applicable. This device is a manufactured medical implant, not an AI/machine learning algorithm that requires a "training set."
9. How the Ground Truth for the Training Set Was Established
Not applicable, as there is no training set for this type of device.
§ 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.