iTotal Posterior Stabilized (PS) Knee Replacement System
K142404 · Conformis, Inc. · JWH · Dec 11, 2014 · Orthopedic
Device Facts
Record ID
K142404
Device Name
iTotal Posterior Stabilized (PS) Knee Replacement System
Applicant
Conformis, Inc.
Product Code
JWH · Orthopedic
Decision Date
Dec 11, 2014
Decision
SESE
Submission Type
Special
Regulation
21 CFR 888.3560
Device Class
Class 2
Attributes
Therapeutic
Indications for Use
The iTotal PS 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 compartments, such as a unicondylar, patellofemoral or bicompartmental prosthesis. The Indications for Use include: - Painful joint disease due to osteoarthritis, traumatic arthritis, rheumatoid arthritis 0 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 o implants. - Revision procedures provided that anatomic landmarks necessary for alignment and o positioning of the implant are identifiable on patient imaging scans This implant is intended for cemented use only.
Device Story
Patient-specific, tricompartmental, cruciate-sacrificing, semi-constrained, fixed-bearing total knee replacement system. Input: patient CT scan data. Process: proprietary and off-the-shelf software designs patient-specific implants and ancillary surgical instruments to match patient geometry/anatomy. Output: custom femoral (CoCrMo), tibial (CoCrMo tray, UHMWPE insert), and patellar (UHMWPE or Vitamin E infused polyethylene) components; single-use biocompatible nylon surgical instruments. Used in clinical settings by surgeons for total knee arthroplasty; indicated when collateral ligaments are intact or posterior cruciate ligament is compromised/absent. Instruments assist in intra-operative positioning and bone cutting. Benefits: personalized fit based on patient-specific anatomy.
Clinical Evidence
No clinical data. Substantial equivalence demonstrated via bench testing: femoral component fatigue, tibial insert spine-femoral cam fatigue, range of motion analysis, and cadaveric evaluation.
Indicated for patients with knee joint pain and disability requiring total knee replacement, including osteoarthritis, traumatic arthritis, rheumatoid arthritis, osteonecrosis, post-traumatic loss of function, moderate varus/valgus/flexion deformity, or failed prior partial/bicompartmental implants. Suitable for revision procedures if anatomic landmarks are identifiable on imaging. Intended for cemented use only.
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
ConforMIS iTotal PS Knee Replacement System (K140833)
Submission Summary (Full Text)
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Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002
December 11, 2014
ConforMIS Incorporated Ms. Amita Shah Senior Vice President Regulatory and Quality Affairs 28 Crosby Drive Bedford, Massachusetts 01730
Re: K142404
Trade/Device Name: iTotal Posterior Stabilized (PS) Knee Replacement 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 Dated: November 12, 2014 Received: November 13, 2014
Dear Ms. Shah:
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 CFR Part 807); labeling (21 CFR Part 801); medical device reporting (reporting of medical
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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 Industry and Consumer Education at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address
http://www.fda.gov/MedicalDevices/Resourcesfor You/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/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.
You may obtain other general information on your responsibilities under the Act from the Division of Industry and Consumer Education 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 Director Division of Orthopedic Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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### Indications for Use
510(k) Number (if known): _K142404
### Device Name:
ConforMIS iTotal Posterior Stabilized (PS) Knee Replacement System (iTotal PS KRS)
### Indications for Use:
The iTotal PS 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 compartments, such as a unicondylar, patellofemoral or bicompartmental prosthesis.
The Indications for Use include:
- Painful joint disease due to osteoarthritis, traumatic arthritis, rheumatoid arthritis 0 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 o implants.
- Revision procedures provided that anatomic landmarks necessary for alignment and o positioning of the implant are identifiable on patient imaging scans
### This implant is intended for cemented use only.
Prescription Use × Over-The-Counter Use AND/OR (Part 21 CFR 801 Subpart D) (21 CFR 801 Subpart C) (PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
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## 8.0 510(K) SUMMARY (PAGE 1 OF 4)
| Submitter's Name and<br>Address: | ConforMIS, Inc.<br>28 Crosby Drive<br>Bedford, MA 01730 |
|-----------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Establishment Registration<br>Number: | 3009844603 and 3004153240 |
| Date of Summary: | August 25, 2014 |
| Contact Person:<br>Telephone Number:<br>Fax Number: | Amita S. Shah, Sr. Vice President, Regulatory and Quality Affairs<br>(781) 345-9164<br>(781) 345-0147 |
| Name of the Device: | ConforMIS iTotal® Posterior Stabilized Knee Replacement System<br>(iTotal PS KRS) |
| Common Name: | Posterior Stabilized Total Knee Replacement System |
| Regulatory Status and<br>Regulation Number: | Class II<br>21 CFR 888.3560 |
| Classification Name: | Knee joint patellofemorotibial polymer/metal/polymer semi-constrained<br>cemented prosthesis |
| Device Classification: | Product Code:<br>JWH: Knee joint patellofemorotibial polymer/metal/polymer semi-<br>constrained cemented prosthesis. |
| | OOG: Knee Arthroplasty Implantation System.<br>Intended to be used to assist in the implantation of a specific knee<br>arthroplasty device or a set of specific knee arthroplasty devices.<br>Indicated to include guiding alignment, making or establishing cuts,<br>selecting, sizing, attaching, positioning or orienting implant<br>components. |
| | OIY: prosthesis, knee, patellofemorotibial, semi-constrained, cemented,<br>polymer + additive/metal/polymer + additive.<br>This generic type of device includes prosthesis that have a femoral<br>component made of alloys, such as cobalt-chromium-molybdenum, and<br>a tibial component(s) and/or a retropatellar resurfacing component<br>made of ultra-high molecular weight polyethylene plus an additive, such<br>as a-tocopherol. |
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### 510(K) SUMMARY (PAGE 2 OF 4)
Indications for Use: The iTotal PS 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, patellofemoral or bicompartmental prosthesis. The Indications for Use include: Painful joint disease due to osteoarthritis, traumatic arthritis, . rheumatoid arthritis, polyarthritis or osteonecrosis of the knee. Post traumatic loss of joint function. .
- o Moderate varus, valgus or flexion deformity.
- Failed osteotomies, hemiarthroplasties, and unicondylar, patellofemoral or bicompartmental implants.
- o 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.
ldentification of the Legally Marketed Device (Predicate Device):
ConforMIS iTotal PS Knee Replacement System (ITOTAL PS KRS) Device Class: ll Product Code: JWH, OOG, OIY Regulation Number: 21 CFR 888.3560 510(k) Number: K140833
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### 510(K) SUMMARY (PAGE 3 OF 4)
Device Description: 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.
> The system is intended to treat patients who are candidates for total knee arthroplasty where the collateral ligaments are intact. Use of the iTotal PS KRS is usually based on surgeon preference, but it may be also used when total knee replacement is indicated and the posterior cruciate ligament is compromised, absent, or surgically excised.
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, ancillary orthopedic manual surqical instruments designed for use with the iTotal PS KRS are provided to assist with implantation. The ancillary instruments are made from biocompatible nylon, and similar to the implants, 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 cutting of bone.
The intended use and function of the patient specific ancillary instruments remain similar to those described in the predicate 510(k)s (K140833).
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### 510(K) SUMMARY (PAGE 4 OF 4)
Substantial Equivalence: The proposed iTotal Posterior Stabilized Knee Replacement System, which consists of minor modifications to the posterior stabilizing features of the femoral implant, is substantially equivalent in design and functionality to the iTotal Posterior Stabilized Knee Replacement System (K140833, cleared June 30, 2014). The following non-clinical laboratory tests were performed to determine substantial equivalence: . Femoral Component Fatique Testing Tibial Insert Spine-Femoral Cam Fatique Testing . Range of Motion Analysis ● Cadaveric Evaluation ● All testing has demonstrated that the device is substantially equivalent to the predicate devices. Description and Nonclinical Testing: The determination of substantial equivalence for Conclusion of Testing: this device was based on a detailed device description and non-clinical laboratory testing. The following non-clinical laboratory tests were performed to determine substantial equivalence: Femoral Component Fatigue Testing . Tibial Insert Spine-Femoral Cam Fatique Testing . Range of Motion Analysis ● Cadaveric Evaluation . Test results demonstrated that the device is safe and can be considered substantially equivalent to the predicate devices for the intended use. The determination of substantial equivalence for this device was based Safety and Performance: on a detailed device description and non-clinical laboratory testing. The testing demonstrated that the device is safe for its intended use and can be considered substantially equivalent to the predicate devices. Clinical data is not necessary to demonstrate substantial equivalence. Conclusion: Based on the testing conducted, it is concluded that the iTotal Posterior Stabilized Knee Replacement System is substantially equivalent to the predicate device: the iTotal Posterior Stabilized Knee Replacement System (K140833, cleared June 30, 2014).
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Part 1 — Search, results, and everyday workflows 16 min
Part 2 — Embeddings: the galaxy map 3 min
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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Exact vs. fuzzy search: what's the difference?
Exact matches on the literal phrase (prefix search works, suffix does not). Fuzzy matches on the meaning and intent of the phrase rather than the exact words. Hover over the badge on any row to see why it matched.
You search "coronary artery calcification" and want only software devices with AI. What two filters do you apply?
Narrow by SaMD (software-only devices), then narrow by AI/ML (devices with AI).
2. The results table
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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Scroll right in the search results table. The intended use column is extracted for you; no need to dig into the 510(k) summary PDF.
What does the AI Performance sub-table show, and why is it useful?
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.
How do you judge how far down fuzzy search results to go?
Use the relevancy signals: the fuzzy badge explanations, the intended use column, and whether the target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, results are trailing off in relevancy.
4. Device detail page: chat and citations
Click a device name to open its detail page: device facts on the left, a chat window on the right. Ask something like "Describe the training data". The answer carries little citation bubbles — click one to jump to the highlighted passage in the source PDF, so you can verify every AI answer against the document. There's also a Download PDF button for sharing.
How do you verify an AI chat answer on the device detail page?
Click the citation bubbles to jump to the relevant highlight in the source document.
Reading rule for every project: how many summaries do you read in full?
At least the three most relevant 510(k) or De Novo summaries, in full. After that, use targeted chat questions to confirm your memory quickly. The tool supports this professional habit — it doesn't replace it.
5. Side-by-side comparison
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.
What does the side-by-side PDF viewer mode do?
Select multiple devices, open the PDF viewer tab, and ask one question (e.g., "Describe the training data"). It queries all selected devices simultaneously with citations, so you can compare and contrast quickly.
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With rows selected, go to the Collections tab and create a labeled collection (e.g., "Cobb Angle Project"). Reload that selection any time — before a client call, pull up the collection and ask questions across all of its devices at once.
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Select the rows, go to the Collections tab, and create a labeled collection (e.g., "Cobb Angle Project"). You can reload the selection anytime and carry it into the PDF viewer and other tabs that support selections.
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What can you do from the regulations tree view?
Browse product codes and regulation numbers, read the identification text and special controls, browse sibling product codes, open device PDFs on the right, and search by product code or regulation number at the top of the tree.
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Click Show Chart and segment by regulation number (or product code) to see which regulations dominate your result set. Clicking a regulation takes you into the regulations tree. Great for spotting that most matches are, say, hardware laparoscopic devices — a cue to go back and filter.
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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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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.