(204 days)
Wright's PROPHECY® Pre-Operative Navigation Alignment Guides are intended to be used as patient-specific surgical instrumentation to assist in the positioning of total knee replacement components intra-operatively and in guiding the marking of bone before cutting. The PROPHECY® Pre-Operative Navigation Alignment Guides are intended for use with Wright's ADVANCE® Total Knee System and its cleared indications for use, provided that anatomic landmarks necessary for alignment and positioning of the implant are identifiable on patient imaging scans. The PROPHECY® Pre-Operative Navigation Alignment Guides are intended for single use only.
PROPHECY® Pre-Operative Navigation Alignment Guides are patient-specific guides created to fit the contours of the patient's distal femoral and tibial plateau anatomy. The guides are designed and manufactured from patient imaging data (MRI, CT), and are available in two versions: alignment and alignment and resection. The guides are made from biocompatible nylon, and the resection slots are biocompatible stainless steel. The PROPHECY® Guides serve as a alternative to traditional alignment instrumentation used with Wright's ADVANCE® Total Knee System, and thereby reduce the overall number of surgical steps required during total knee arthroplasty. The guides serve to position and align the ADVANCE® implants in a comparable position to traditional ADVANCE® instruments.
The provided text describes a 510(k) premarket notification for the PROPHECY® Pre-Operative Navigation Alignment Guides. This type of submission relies on proving substantial equivalence to a predicate device, rather than conducting new clinical efficacy studies with specific acceptance criteria and performance metrics in the same way a PMA or a de novo device would. The document focuses on demonstrating that the new device is as safe and effective as existing legally marketed devices.
Therefore, many of the requested data points (like an explicit table of acceptance criteria and reported device performance, sample sizes for training/test sets, expert adjudication methods for ground truth, or MRMC studies) are not provided in this type of submission. The "performance data" mentioned refers to engineering and cadaver testing to validate the design and manufacturing process, not a clinical study to establish performance against pre-defined clinical acceptance criteria.
Here's a breakdown of the information that is available based on the provided text, and where gaps exist due to the nature of a 510(k) submission:
Acceptance Criteria and Device Performance:
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Not explicitly defined in terms of clinical outcomes or specific performance metrics for the device itself. The submission aims to demonstrate substantial equivalence to a predicate device (ADVANCE® Total Knee System instruments) in assisting with surgical alignment. | The submission claims that the PROPHECY® Guides serve to position and align the ADVANCE® implants in a comparable position to traditional ADVANCE® instruments. This is supported by: Cadaver testing by end users analyzing placement location and orientation.Repeatability testing across design engineers.Detailed software descriptions and documentation.Biocompatibility testing. |
Study Details:
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Sample size used for the test set and the data provenance:
- Test Set Sample Size: Not explicitly stated. The "cadaver testing" likely involved a limited number of cadavers, but the exact count is not provided.
- Data Provenance: The cadaver testing and repeatability testing are internal studies conducted by Wright Medical Technology, Inc. No country of origin for specific data is mentioned beyond the company's US headquarters. The studies are prospective (conducted to validate the device).
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Number of Experts: Not specified. The document mentions "end users" for cadaver testing, implying surgeons or individuals knowledgeable in total knee arthroplasty, but their number and specific qualifications (e.g., years of experience, board certification) are not detailed.
- Qualifications of Experts: The document implies "end users" would be those who perform surgical procedures, suggesting they are qualified to assess placement and orientation.
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Adjudication method (e.g., 2+1, 3+1, none) for the test set:
- Adjudication Method: Not specified. Given the nature of cadaver testing and engineering repeatability testing, it's unlikely a formal adjudication method like 2+1 or 3+1 was used in the clinical trial sense. The focus would have been on measurement consistency and adherence to predetermined design goals.
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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:
- MRMC Study: No. This device is a physical surgical guide, not an AI-based diagnostic or assistive software that would typically involve human readers interpreting images. The closest analog would be comparing surgical outcomes with and without the guides, but this was not an MRMC study.
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If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Standalone Performance: The "device design algorithm" mentioned is part of the manufacturing process to create the patient-specific guides. "User repeatability testing and cadaver testing" were done to ensure the repeatability of this design algorithm's execution and guide performance in a simulated surgical environment. However, this is not a "standalone" clinical performance assessment in the sense of a medical imaging AI algorithm. The device requires a human (surgeon) to use it.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- Type of Ground Truth: For the cadaver testing, the "ground truth" would likely be based on surgical measurements and anatomical landmarks, aiming to achieve specific alignment angles and implant positions as determined by established surgical principles or desired targets. For repeatability testing, the ground truth would be the consistent output of the manufacturing process or design algorithm. It's not pathology or outcomes data from live patients.
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The sample size for the training set:
- Training Set Sample Size: Not applicable in the context of this device's validation. The device is manufactured based on individual patient imaging data (MRI, CT). While the design algorithm might have been developed using existing knowledge of knee anatomy and surgical principles, there's no "training set" in the machine learning sense explicitly described for the device itself.
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How the ground truth for the training set was established:
- Training Set Ground Truth: Not applicable, as there's no explicitly defined training set for the device in this document. The "ground truth" for the design of the guides would implicitly be based on established anatomical parameters and surgical objectives for total knee replacement, drawing upon decades of orthopedic knowledge and experience.
§ 888.3565 Knee joint patellofemorotibial metal/polymer porous-coated uncemented prosthesis.
(a)
Identification. A knee joint patellofemorotibial metal/polymer porous-coated uncemented 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 is designed to achieve biological fixation to bone without the use of bone cement. This identification includes fixed-bearing knee prostheses where the ultra high molecular weight polyethylene tibial bearing is rigidly secured to the metal tibial base plate.(b)
Classification. Class II (special controls). The special control is FDA's guidance: “Class II Special Controls Guidance Document: Knee Joint Patellofemorotibial and Femorotibial Metal/Polymer Porous-Coated Uncemented Prostheses; Guidance for Industry and FDA.” See § 888.1 for the availability of this guidance.