(131 days)
Total Knee Replacement
The Zimmer® Patient Specific Instruments System is intended to be used as a surgical instrument to assist in the positioning of Total Knee Replacement components intraoperatively and in guiding the marking of bone before cutting provided that anatomic landmarks necessary for alignment and positioning of the implant are identifiable on patient imaging scans.
The Zimmer® Patient Specific Instruments System is to be used with Zimmer NexGen CR-Flex fixed bearing, Zimmer NexGen CR fixed bearing, Zimmer NexGen LPS-Flex fixed bearing, Zimmer NexGen LPS fixed bearing, Zimmer Gender Solutions Natural – Knee Flex fixed bearing, Zimmer Persona™ CR fixed bearing, Zimmer Persono™ PS fixed bearing and Zimmer Persona™ Trabecular Metal™ prostheses families only.
Unicompartmental Knee Replacement
The Zimmer® Patient Specific Instruments System is intended to be used as a surgical instrument to assist in the positioning of Unicompartmental Knee Replacement components intra-operatively and in guiding the marking of bone before cutting and to guide cutting of the bone provided that anatomic landmarks necessary for alignment and positioning of the implant are identifiable on patient imaging scans.
The Zimmer® Patient Specific Instruments System is to be used with Zimmer Unicompartmental High Flex Knee System prostheses families only.
The Zimmer® Patient Specific Instruments are intended for single use only.
The subject 'device Zimmer® Patient Specific Instruments System 5.4 is a modification to the predicate device Zimmer® Patient Specific Instruments System 5.0 (K121640) to accommodate the new compatible implant system Zimmer® Personalized Knee System Trabecular Metal™ components cleared via 510(k) K122745 and K121771. It is designed to assist a surgeon in the placement of total knee replacement components for Zimmer® Persono™ Trabecular Metal™ components. The system consists of a software device, branded as Zimmer® Patient Specific Instruments Planner (ZPSIP) and a hardware component, branded as Zimmer® Patient Specific Instruments (ZPSI).
Here's an analysis of the provided text regarding the Zimmer Patient Specific Instruments System 5.4, addressing your specific questions:
1. Table of Acceptance Criteria and Reported Device Performance
The provided 510(k) summary does not explicitly state specific acceptance criteria in a quantitative manner (e.g., target accuracy percentages, deviation limits). Instead, it relies on the concept of "substantial equivalence" to a predicate device.
| Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|
| Safety and effectiveness substantially equivalent to predicate device (Zimmer Patient Specific Instruments System 5.0 (K121640)). | "Testing verified that the accuracy and performance of the system is adequate to perform as intended." |
| "Results of software verification and validation testing demonstrated the device's safety and effectiveness is substantially equivalent to the predicate device." | |
| Accuracy and performance adequate for intended surgical assistance. | "Testing verified that the accuracy and performance of the system is adequate to perform as intended." |
| "A detailed comparison shows the subject device is substantially equivalent in intended use, design, functionality, operating principles, materials and performance characteristics to the predicate devices." |
2. Sample Size Used for the Test Set and Data Provenance
The document mentions "Non-clinical tests using saw bones" for performance evaluation.
- Sample Size for Test Set: Not specified in the provided text.
- Data Provenance: The tests were "Non-clinical" and used "saw bones." This implies an in vitro or laboratory setting, not patient data. No country of origin is mentioned for this testing. It is a retrospective analysis of the device's performance under controlled conditions, not utilizing patient data.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
The document does not provide information on the number of experts used or their qualifications for establishing ground truth specific to the saw bone testing. Since it's saw bone testing, the "ground truth" would likely be established by precise measurements or engineering specifications rather than expert medical interpretation.
4. Adjudication Method for the Test Set
The document does not specify any adjudication method. Given the nature of saw bone testing, where physical measurements confirm accuracy, expert adjudication in the typical clinical sense would not be applicable.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and Effect Size
No, a multi-reader multi-case comparative effectiveness study was not mentioned. The evaluation primarily focuses on the device's standalone performance in a non-clinical setting and its substantial equivalence to a predicate, not on how it improves human reader performance.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
Yes, a standalone performance evaluation was done. The "Non-clinical tests using saw bones" without mention of human interaction suggests a standalone evaluation of the device's accuracy and performance. The software device, Zimmer Patient Specific Instruments Planner (ZPSIP), generates a pre-surgical plan, and the hardware (ZPSI) transfers this plan. The testing verifies the system's ability to "perform as intended" in this capacity, i.e., accurate planning and guidance.
7. Type of Ground Truth Used
The ground truth for the saw bone testing would be based on physical measurements and engineering specifications against the planned surgical cuts/positions. For example, if the device is intended to guide a cut at a specific angle, the ground truth would be the actual measured angle of the cut made on the saw bone. It is not expert consensus, pathology, or outcomes data, as these are typically associated with human patient clinical data.
8. Sample Size for the Training Set
The document does not provide any information regarding a training set. This is a medical device clearance based on substantial equivalence, and typical AI/ML "training sets" are not explicitly mentioned as part of the evaluation. The software component, ZPSIP, implies some form of algorithmic processing, but the development and training details are not disclosed in this summary.
9. How the Ground Truth for the Training Set Was Established
As no training set is described, there is no information on how its ground truth was established.
§ 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.