(25 days)
The iTotal® CR Knee Replacement System (KRS) is intended for use as a total knee replacement in patients with knee joint pain and disability whose conditions cannot be solely addressed by the use of a prosthetic device that treats only one or two of the three knee compartments, such as a unicondylar, patello-femoral or bi-compartmental prosthesis.
The indications for use include :
- Painful joint disease due to osteoarthritis, traumatic arthritis, rheumatoid arthritis or osteonecrosis of the knee.
- Post traumatic loss of joint function.
- Moderate varus, valgus or flexion deformity in which the ligamentous structures can be returned to adequate function and stability.
- Failed osteotomies, hemiarthoplasties, and unicondylar, patello-femoral or bi-compartmental implants.
The iTotal CR KRS is intended for cemented use only.
The iTotal CR Knee Replacement System (hereafter referred to as the "iTotal CR KRS") is a patient specific tricompartmental faceted posterior cruciate ligament (PCL) retaining knee replacement system. The iTotal CR KRS is a semi-constrained cemented knee implant which consists of a femoral, tibial and patellar component. The product design incorporates a bone preserving approach with minimal bone resection of the tibia and femur for the treatment of severe pain and/or disability of a knee damaged by osteoarthritis or trauma.
Using patient imaging (either CT or MR scans) and a combination of proprietary and off the shelf software a patient-specific implant and related instrumentation are designed, that best meet the geometric and anatomic requirements of the specific patient. The femoral component is manufactured from cobalt chromium molybdenum ("CoCrMo") alloy. The tibial component includes a metal tray manufactured from CoCrMo alloy and either one or two polyethylene inserts manufactured from UHMWPE of identical configuration. The patellar component is manufactured from UHMWPE.
For user convenience, and similar to the predicate iTotal CR KRS, accessory orthopedic manual surgical instruments designed for use with the modified iTotal CR KRS are provided to assist with implantation. The ancillary instruments are provided sterile and for single-use only. These patient specific instruments are provided to assist in the positioning of total knee replacement components intra-operatively and in guiding the marking of bone before cutting. The function and general design features of the patient specific ancillary instruments remain similar to those described in the predicate 510k i.e. K094050, K103117 and K112780.
The provided text describes the KonforMIS iTotal CR Knee Replacement System, but it is a Knee Replacement System, not an AI/ML powered medical device. As such, the standard acceptance criteria and study methodologies for AI/ML devices (e.g., sensitivity, specificity, MRMC studies, ground truth establishment methods) are not applicable.
The document pertains to a 510(k) premarket notification for a traditional medical device, specifically a modified version of an existing knee replacement system. The focus of the submission and the FDA's review is on demonstrating substantial equivalence to existing legally marketed predicate devices, rather than establishing performance against specific AI/ML metrics.
Therefore, many of the requested fields cannot be filled as they are not relevant to this type of device and submission.
Here's a breakdown of the available information regarding its 'acceptance criteria' (which in this context means demonstrating substantial equivalence) and the 'study' (which is non-clinical testing):
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (for Substantial Equivalence to Predicate) | Reported Device Performance |
|---|---|
| Components: Identical to predicate device | Identical (Femoral, Tibial, Metal Backed Tibial, Patellar components) |
| Materials: Identical to predicate device | Identical (CoCrMo for femoral/tibial tray, UHMWPE for tibial/patellar inserts) |
| Design: Identical to predicate device | Identical (Knee joint patellofemorotibial semi-constrained cemented prosthesis) |
| Principle of Operation: Identical to predicate device | Identical (Cemented Use fixed Bearing Design) |
| Patient Matched: Identical to predicate device | Identical (Yes) |
| Patellar Design/Dimensions: Identical to predicate device | Identical (Symmetrical, offered in various sizes) |
| Minimum Thickness Tibial Insert (UHMWPE): Identical to predicate device | Identical (6 mm) |
| Posterior Cruciate Ligament (PCL) Sparing: Identical to predicate device | Identical (Yes) |
| Instrumentation: Patient specific Nylon jigs | Patient specific Nylon jigs (similar to predicate, but new proprietary software for femoral iJig). |
| Proprietary Software for femoral iJig instrumentation: (New element) Demonstrated functionality and safety through software verification and validation testing. | iTotal FemJigs version 1.0 - Software verification and validation testing performed. |
Note: The "acceptance criteria" here are implicitly about demonstrating that the modified device is as safe and effective as the predicate device(s) through a comparison of physical and functional characteristics, and specifically for the new software component, through verification and validation.
2. Sample size used for the test set and the data provenance
Not applicable. This is a medical device, not an AI/ML model for diagnostic or prognostic purposes with a 'test set' of patient data in the conventional sense. The "test set" refers to the proprietary software verification and validation, which would involve software testing rather than patient data.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
Not applicable. No ground truth established by experts is mentioned for this type of device. The determination of substantial equivalence relies on device comparison and non-clinical testing data.
4. Adjudication method for the test set
Not applicable. Not an AI/ML device with a human-adjudicated test set.
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
Not applicable. This is not an AI-assisted diagnostic or prognostic device, and no human reader study was conducted for this 510(k) submission.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Not applicable. The proprietary software is part of the instrumentation for the surgeon as a human-in-the-loop tool, it is not a standalone algorithm performing a diagnostic task. The software itself underwent "software verification and validation testing," which is a standalone assessment of the software's functionality and correctness, but not in the context of diagnostic performance metrics.
7. The type of ground truth used
Not applicable. The "ground truth" concept as applied to AI/ML to validate diagnostic accuracy is not relevant here. The device's safety and effectiveness are established through comparison to a predicate device and engineering testing.
8. The sample size for the training set
Not applicable. The software described is for patient-specific implant and instrumentation design, not an AI/ML model that is 'trained' on a dataset in the typical sense.
9. How the ground truth for the training set was established
Not applicable, as there's no 'training set' for an AI/ML model as described in the conventional sense.
§ 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.