(29 days)
The iTotal® PS Knee Replacement System 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, patellofemoral or bicompartmental prosthesis.
The Indications for Use include:
- Painful joint disease due to osteoarthritis, traumatoid arthritis, polyarthritis, polyarthritis or osteonecrosis of the knee.
- Post traumatic loss of joint function.
- Moderate varus, valgus or flexion deformity.
- Failed osteotomies, hemiarthroplasties, and unicondylar, patellofemoral or bicompartmental implants.
- Revision procedures provided that anatomic landmarks necessary for alignment and positioning of the implant are identifiable on patient imaging scans
This implant is intended for cemented use only.
The iTotal Posterior Stabilized Knee Replacement System (hereafter referred to as the "iTotal PS KRS") is a patient specific tricompartmental faceted, cruciate sacrificing knee replacement system. The iTotal PS KRS is a semi-constrained, fixed bearing, cemented knee implant which consists of a femoral, tibial and patellar component.
Using patient imaging (CT scan) and a combination of proprietary and off the shelf software, a patient specific implant is designed, that best meets 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 a polyethylene insert that is manufactured from ultra-high molecular weight polyethylene (UHMWPE). The patellar component is manufactured from either UHMWPE or from a highly cross-linked Vitamin E infused polyethylene (iPoly XE™).
For user convenience, and similar to the predicate iTotal PS KRS, patient specific accessory orthopedic manual surgical instruments designed for use with the proposed iTotal PS KRS are provided to assist in the positioning of the total knee replacement components intraoperatively and in guiding the cutting of bone. These instruments are single use only and may be provided sterile. In addition, reusable orthopedic manual surgical instruments are provided separately.
The function and general design features of the patient specific implants and ancillary instruments remain similar to those described in the predicate 510(k)s K160025 & K153217.
This document describes the ConforMIS iTotal® Posterior Stabilized (PS) Knee Replacement System (iTotal PS) and its substantial equivalence determination. However, it does not contain information about acceptance criteria for device performance or a study demonstrating the device meets specific performance criteria in the way typical for AI/ML device evaluations.
The "study" referenced in this document concerns software verification and validation, aimed at demonstrating substantial equivalence to a previously cleared predicate device, rather than a clinical performance study with acceptance criteria and ground truth.
Therefore, many of the requested fields cannot be directly answered from the provided text.
Here is a breakdown of what can be answered and what cannot:
1. A table of acceptance criteria and the reported device performance:
- Acceptance Criteria: Not explicitly stated as performance metrics with thresholds in this document. The "acceptance criteria" here implicitly refer to meeting the requirements for demonstrating substantial equivalence to predicate devices, particularly regarding software verification and validation.
- Reported Device Performance: The document states that "Non-clinical laboratory testing was performed demonstrating that the device can be considered substantially equivalent to the predicate device for the intended use." The specific performance metrics for the device itself (e.g., accuracy of cuts, implant fit) are not reported in this summary, nor are quantitative acceptance criteria for such metrics.
2. Sample sized used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective):
- This information is not provided in the document. The "tests" mentioned are software verification and validation, not clinical test sets with patient data.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not applicable as this document focuses on software validation and substantial equivalence, not a clinical study requiring expert-established ground truth for a test set.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- Not applicable.
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/ML diagnostic or assistive device in the context of human reader improvement. The software generates patient-specific surgical guides, not interpretations for human readers.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- The document implies that the "iTotal FemJigs PS v1.0" and "iTotal TibJigs PS v1.0" software modules automate the generation of iJigs. The "software verification and validation testing" performed on these proprietary software modules could be considered a form of standalone testing for the algorithm's output (i.e., the iJigs design). However, specific performance metrics for this standalone algorithm are not presented.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- For the software verification and validation, the ground truth would likely involve established engineering specifications, design requirements, and comparisons against outputs generated by the previous manual process or predicate software versions. It is not clinical ground truth like pathology or outcomes data.
8. The sample size for the training set:
- This information is not provided. The document describes software that "automates the generation of the iTotal PS iJigs" using "proprietary software modules iTotal FemJigs PS v1.0 and iTotal TibJigs PS v1.0". It doesn't explicitly state that these modules comprise a machine learning model that requires a "training set" in the conventional sense. It's possible the software uses rule-based systems or sophisticated algorithms developed through engineering rather than machine learning on a large dataset.
9. How the ground truth for the training set was established:
- Not applicable, as a training set is not explicitly mentioned or implied to be used for machine learning in the conventional sense. If the software involves AI/ML, this information is not disclosed.
Summary from the document:
The ConforMIS iTotal® PS Knee Replacement System (iTotal PS) received a 510(k) clearance based on its substantial equivalence to predicate devices (K160025 and K153217). The primary focus of this submission was on modifications involving the automation of the generation of iTotal PS iJigs (surgical guides) using new proprietary software modules (iTotal FemJigs PS v1.0 and iTotal TibJigs PS v1.0).
The study that "proves the device meets the acceptance criteria" in this context is the software verification and validation testing performed on these new proprietary software modules. The "acceptance criteria" were met by demonstrating that the modifications did not alter the fundamental technological characteristics, materials, design, manufacturing, packaging, or sterilization of the device and that the new automated process was equivalent to the previous methods (manual or older software).
The document states: "Non-clinical laboratory testing was performed demonstrating that the device can be considered substantially equivalent to the predicate device for the intended use. The following non-clinical laboratory testing was performed: Detailed software description and software verification and validation testing of proprietary software iTotal FemJigs PS v1.0. Detailed software description and software verification and validation testing of proprietary software iTotal TibJigs PS v1.0."
§ 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.