The CAS PSI Knee System is indicated as an orthopedic instrument system to assist in the positioning of knee replacement components. It involves surgical planning software used pre-operatively to plan the surgical placement of the components on the basis of provided patient radiological images with identifiable placement anatomical landmarks, and surgical instrument components that include patient specific or customized guides fabricated on the basis of the surgical plan to precisely reference the placement of the implant components intra-operatively per the surgical plan. The CAS PSI Knee System is to be used with the following fixed bearing knee replacement systems in accordance with their indications and contraindications: NexGen CR, NexGen CR-Flex, Nexgen CR-Flex Gender, Nexgen LPS, Nexgen LPS-Flex, Nexgen LPS-Flex Gender, Persona CR, and Persona PS. The patient specific guide components are intended for single-use only.
Device Story
CAS PSI Knee System is an orthopedic instrument system for pre-operative surgical planning and intra-operative positioning of knee replacement components. Input: patient radiological images (MRI). Process: surgical planning software models patient anatomy, identifies landmarks, and plans implant placement; system fabricates patient-specific guides (femoral and tibial) and 3D bone models. Output: patient-specific guides and 3D bone models used by surgeons in the OR to align and position implants. System includes drop rod adaptors for intra-operative alignment validation. Benefits: improved accuracy of implant placement relative to patient anatomy. Used in clinical settings by orthopedic surgeons.
Clinical Evidence
No clinical data. Performance verified via non-clinical bench testing: software system/performance tests (accuracy/reproducibility of algorithms, segmentation, meshing, landmark assignment), guide mechanical resistance tests (breakage, debris, aging, sterilization), and full system validation using cadaver specimens and sawbones to verify ergonomics and usage.
Technological Characteristics
System comprises pre-operative planning software and patient-specific surgical guides. Guides are patient-specific, single-use. Software performs anatomical modeling, landmark identification, and jig creation. Connectivity: standalone software. Sterilization: guides are provided sterile or sterilized by the user (implied). Algorithm: proprietary planning and jig creation algorithms.
Indications for Use
Indicated for patients undergoing knee replacement surgery requiring assistance in positioning components. Compatible with NexGen CR, NexGen CR-Flex, Nexgen CR-Flex Gender, Nexgen LPS, Nexgen LPS-Flex, Nexgen LPS-Flex Gender, Persona CR, and Persona PS systems. Contraindications are those of the specific knee replacement systems used.
Regulatory Classification
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).
Predicate Devices
Zimmer Patient Specific Instruments System 5.0 (K121640)
Zimmer Patient Specific Instruments System 5.0 (K111492)
Submission Summary (Full Text)
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# 510(K) SUMMARY OF SAFETY AND EFFECTIVENESS CAS PSI KNEE SYSTEM
Applicant: Zimmer CAS 75 Queen Street, suite 3300 Montreal, Quebec Canada, H3C 2N6 Tel .: 514 861 4074 Fax: 514 866 2197
SEP 1 3 2013
Contact Person: Christopher McLean
Date Summary Prepared: August 15, 2013
Device Trade Name: CAS PSI Knee System
## Device Name / Product Code, Regulation Classification Name / Number:
1) Knee Arthroplasty Implantation System / OOG, Knee Joint Patellofemorotibial Polymer/Metal/Polymer Semi-Constrained Cemented Prosthesis / 21 CFR § 888.3560 2) Prosthesis, knee, patellofemorotibial, semi-constrained, cemented, polymer/metal/polymer / JWH. Knee Joint Patellofemorotibial Polymer/Metal/Polymer Semi-Constrained Cemented Prosthesis / 21 CFR § 888.3560 3) Prosthesis. Knee, Patello/Femorotibial, Semi-Constrained, Uncemented, Porous. Coated, Polymer/Metal / MBH, Knee Joint Patellofemorotibial Metal/Polymer Porous-Coated Uncemented Prosthesis / 21 CFR & 888.3565
## Predicate Devices:
- 1. Zimmer Patient Specific Instruments System 5.0, Submitter: Materialise N.V., K121640
- 2. Zimmer Patient Specific Instruments System 2.5, Submitter: Materialise N.V., KI11492
# Device Description:
The CAS PSI Knee is an orthopedic instrument system indicated to assist in the positioning of knee replacement components. It involves surgical planning software used pre-operatively, and surgical instrument components that include patient specific guides to precisely align and position the implant components intra-operatively relative to each patient's anatomical features per the surgical plan. The surgical planning software allows the review of patient joint models determined from radiological images upon which the surgical placement of the implant components is adjusted per anatomical landmarks. The patient specific guides are fabricated per the patient models to fit each patient's anatomy with features that set the relative placement of the implant components per the surgical plan. The system is compatible with given implant systems per its indications for use.
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## Indications for Use / Intended Use:
The CAS PSI Knee System is indicated as an orthopedic instrument system to assist in the positioning of knee replacement components. It involves surgical planning software used pre-operatively to plan the surgical placement of the components on the basis of provided patient radiological images with identifiable placement anatomical landmarks, and surgical instrument components that include patient specific or customized guides fabricated on the basis of the surgical plan to precisely reference the placement of the implant components intra-operatively per the surgical plan.
The CAS PSI Knee System is to be used with the following fixed bearing knee replacement systems in accordance with their indications and contraindications: NexGen CR, NexGen CR-Flex, Nexgen CR-Flex Gender, Nexgen LPS, Nexgen LPS-Flex, Nexgen LPS-Flex Gender, Persona CR, and Persona PS.
The patient specific guide components are intended for single-use only.
## Technological Comparisons to the Predicates:
The main technology in the CAS PSI Knee system is the same as in the predicates. Both the CAS PSI Knee system and the predicates involve an equivalent software package to pre-operatively model the patients anatomy from MRI scans, identify surgical landmark on the patient models in accordance with the implant surgical technique to reference the placement of the implants, plan the placement of the implants upon the model and per the surgical landmarks, and to create corresponding models for Femoral and Tibial Guides with surfaces and elements to uniquely fit each patient topographical features and set or reference the placement of the implant system components per the plan.
While the Femoral and Tibial Guides provide the same functions in both the CAS PSI Knee system and the predicates, in the CAS PSI Knee system the tibial guide functions are provided by two guides as compared to one single guide in the predicates. The predicate Tibial Guide combines features to set both the location of the implant tibial cut guides as well as the location of the implant tibial component on the cut surface. In the CAS PSI Knee this is provided by one guide to set the location of the implant system's tibial cut guide, and a separate Tibial Rotational Guide to locate the implant's tibial component on the cut surface. While provided separately the approach is equivalent since the intended use to place the implant component is the same.
Another difference is that the system includes additional instrument accessories called Drop Rod Adaptors. These allow for the intra-operatively validation of the alignment provided by the Tibial Guide while the Tibial Guide is still set on the patient. In the predicates the user is similarly instructed to perform the verification of the alignment of the tibial cut with, however, the difference that it is done only once the cut guide is positioned on the patient after the predicate Tibial Guides have been removed, and also that it is by using the implant's system drop rod adaptors instruments as intended for this While the approach is different, the intended use to verify the alienment purpose. imparted by the Tibial Guides is equivalent.
A final difference is that the CAS PSI Knee system includes full scale 3-D reproductions of the bone models of each patient's distal femur and proximal tibia on which the locations of the guides and reference landmarks are depicted per the surgical planning. These allow the surgeon to visually gage intra-operatively the accuracy of the bone
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models relative to the actual patient's anatomy and the relative placement of the guides
Given their intent to provide more information for the user to gage the per the plan. accuracy of the planning and guides, these do not raise new safety or effectiveness concerns.
# Performance Data:
Four different types of non-clinical tests to were conducted to verify and validate the performance of the system and assess that no new safety and efficacy issues were raised in the device.
- . Software System Tests: They were performed to ensure that no hazardous anomalies were present in the system software components. They consisted of testing software features and functionalities in correspondence to software design requirements.
- Software Performance Tests: Tests were performed to verify the reproducibility o and accuracy of the software system algorithms. These included the accuracy and reproducibility of the software tools, the model meshing and segmentation methods, the assignment of surgical landmarks, the planning method, and the jig creation algorithms.
- Tests were performed to verify the Guide Mechanical Resistance Tests: . mechanical performance of the guides including resistance to use or drop breakage, debris generation, aging stability, sterilization, and extreme shipping conditions.
- Full System Validation Tests: Full use simulations tests using cadaver specimens or . sawbones were performed by multiple surgeons to verify and validate the overall system performance in terms of system usage and instrument ergonomics. The results demonstrated satisfactory performance per the intended use.
## Conclusion:
The information and data provided in the 510(k) Premarket Notification established that the CAS PSI Knee System is substantially equivalent to the predicates.
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Image /page/3/Picture/0 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo features a stylized depiction of an eagle or bird-like figure with three curved lines representing its wings or body. To the left of the bird-like figure, there is a circular seal with text that reads "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the perimeter.
# DEPARTMENT OF HEALTH & HUMAN SERVICES
Public Health Service
September 13, 2013
Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002
Zimmer CAS Mr. Christopher McLean Quality & Regulatory Affairs Associate Director 75 Queen Street, Suite 3300 Montreal, Quebec H3C 2N6 CANADA
Re: K131409 Trade/Device Name: CAS PSI Knee System Regulation Number: 21 CFR 888.3560 Regulation Name: Knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis. Regulatory Class: Class II Product Code: JWH, MBH, OOG Dated: August 15, 2013 Received: August 16, 2013
Dear Mr. McLean:
We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you; however, that device labeling must be truthful and not misleading.
If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21
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## Page 2 - Mr. Christopher McLcan
CFR Part 807); labeling (21 CFR Part 801); medical device reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please contact the Division of Small Manufacturers, International and Consumer Assistance at its tollfree number (800) 638-2041 or (301) 796-7100 or at its Internet address
http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm. Also, please note the regulation entitled. "Misbranding by reference to premarket notification" (21CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to
http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/dcfault.htm for the CDRH's Office of Surveillance and Biometries/Division of Postmarket Surveillance.
You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm.
Sincerely yours.
Mark N. Melkerson -S
Mark N. Melkerson Division Director Division of Orthopedic Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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510(k) Number: K131409
Device Name: CAS PSI Knee System
## Indications for Use:
The CAS PSI Knee System is indicated as an orthopedic instrument system to assist in the positioning of knee replacement components. It involves surgical planning software used pre-operatively to plan the surgical placement of the components on the basis of provided patient radiological images with identifiable placement anatomical landmarks, and surgical instrument components that include patient specific or customized guides fabricated on the basis of the surgical plan to precisely reference the placement of the implant components intra-operatively per the surgical plan.
The CAS PSI Knee System is to be used with the following fixed bearing knee replacement systems in accordance with their indications and contraindications: NexGen CR, NexGen CR-Flex, Nexgen CR-Flex Gender, Nexgen LPS, Nexgen LPS-Flex, Nexgen LPS-Flex Gender, Persona CR, and Persona PS.
The patient specific guide components are intended for single-use only.
Prescription Use _ V (per 21CFR 801.109) OR
Over-the-Counter Use
Concurrence of CDRH, Office of Device Evaluation (ODE)
**Casey Hanley, PhD**
Division of Orthopedic Devices
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1. Search: exact and fuzzy
Type a phrase like "coronary artery calcification" into the search box. You get two kinds of results. Exact results match the literal phrase — prefix searches work ("coronary artery calcificati") but suffix searches do not. Fuzzy results match on the meaning and intent of your phrase rather than the exact words, and are sorted by relevance score. Hover over the Exact or Fuzzy badge on any row to see exactly why it matched.
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Scroll right in the results table. The intended use is extracted for you — no need to open the PDF. The device story gives a high-level snapshot of what the device does and how it's used. The AI Performance sub-table shows each output name, acceptance criteria, observed values, and development/test dataset descriptions — the same format Innolitics uses for regulatory strategy outputs, and the fastest high-level fingerprint of an AI device. It is AI-generated but has been very reliable in practice.
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Output name, acceptance criteria, observed values, development dataset description, and test dataset description. It's the same format we use for regulatory strategy output and Fast 510(k) input, and the fastest high-level fingerprint of an AI device. AI-generated but reliable in practice.
3. Judging fuzzy relevance
Fuzzy results trail off in relevance as you scroll. Use three signals to decide how far down to go: the fuzzy badge explanations, the intended use column, and whether your target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, you're past the relevant zone. A top hit with a low score (~0.4) and a stretched explanation is a hint the closest predicates are far away — the project may be headed for De Novo. Note the fuzzy search is a pattern match: it doesn't handle negation ("not") well, and hardware devices can appear — filter by SaMD/AI ML to cut them.
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Select multiple rows in the results table (aim for under ~10), then open the PDF Viewer tab. Ask one question — it goes to all selected devices in parallel, each with citations. This is the fastest way to compare and contrast devices: training data, PCCP scope, how they handled adding new scanners, and so on.
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Click "Show Chart" and segment by Regulation Number. Clicking a regulation takes you to the regulations tree.
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Open the Predicates tab for a family-tree view of predicate relationships. Click a node to trace its parents and children; selections from search carry over pre-selected. Commonly predicated devices are worth reading — a lot of people predicated them for a reason. The visual lineage is also handy on client calls, e.g. to show how a predicate family evolved and justify why your predicate still holds.
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A lot of people predicated them for a reason. Clicking a node traces parents and children, and selections from search carry over pre-selected.
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The Embeddings tab plots every matching document in a 2-D "galaxy map" where semantically similar devices cluster together. Hover or click clusters to explore, and let AI label the clusters for you. Embeddings beat product codes for grouping: two devices can carry different product codes (LLZ vs. QIH) yet do the same thing — the embedding captures the meaning of the intended use and device story. This is also exactly how retrieval-augmented generation (RAG) works under the hood, and it makes a great visual on client calls.
Try it yourself
Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.