(56 days)
The Mako System is intended to assist the surgeon in providing software defined spatial boundaries for orientation and reference information to anatomical structures during orthopedic procedures.
The Mako System is indicated for use in surgical knee procedures in which the use of stereotactic surgery may be appropriate, and where reference to rigid anatomical bony structures can be identified relative to a CT based model of the anatomy. These procedures include: Total Knee Arthroplasty (TKA).
The implant systems compatible with the system: Triathlon Total Knee System (CR/CS/PS/PSR cemented and cementless primary); Triathlon Total Knee System (TS inserts cemented primary).
The Mako System with the subject Mako Total Knee Application is a stereotactic instrument that includes a robotic arm, an integrated cutting system, an optical detector, a camera, a computer, dedicated instrumentation, an operating software, and tools and accessories. The system's architecture is designed to support total and partial knee procedures and total hip procedures. With application specific hardware and software, the system provides haptic guidance during orthopedic surgical procedures by using patient CT data to assist a surgeon with pre-surgical planning, implant placement, and interpretive/intraoperative navigation of the patient's anatomy.
Once configured for a specific application, the Mako robotic arm can serve as the surgeon's "intelligent" tool holder or tool guide by passively constraining the preparation of an anatomical site for an orthopedic implant with software-defined spatial boundaries.
Based on the provided FDA 510(k) clearance letter for the Mako Total Knee Application (3.0), here's an analysis of the acceptance criteria and the study that proves the device meets them:
Important Note: The provided document is an FDA 510(k) clearance letter, which determines substantial equivalence to a predicate device. It is not a detailed clinical study report. Therefore, specific numerical acceptance criteria and "performance against criteria" for detailed metrics (like sensitivity, specificity, AUC for AI models) common in AI/ML medical devices are not explicitly stated in this document. Instead, the focus is on whether the modifications to the Mako Total Knee Application (3.0) maintain the safety and effectiveness of the existing predicate device (K241011).
The "acceptance criteria" here are generally inferred from the types of non-clinical performance testing conducted to demonstrate that the modified device functions as intended and is as safe and effective as its predicate.
1. Table of Acceptance Criteria and Reported Device Performance
Given the nature of the document (510(k) summary), precise numerical acceptance criteria and corresponding reported performance values are not detailed. The performance data section broadly lists the types of tests conducted.
| Acceptance Criterion (Inferred) | Reported Device Performance (Summary from Document) |
|---|---|
| Functionality & Performance: | |
| Bone Registration Accuracy | Performance testing demonstrates "Bone Registration and Resection Accuracy." |
| Resection Accuracy | Performance testing demonstrates "Bone Registration and Resection Accuracy." |
| Software Functional | "Software Functional Testing" conducted. |
| Software Performance | "Software Performance Verification" conducted. |
| Safety & Verification: | |
| Instrumentation Cleaning | "Instrumentation cleaning, sterility, and biocompatibility assessment" conducted. |
| Sterility | "Instrumentation cleaning, sterility, and biocompatibility assessment" conducted. |
| Biocompatibility | "Instrumentation cleaning, sterility, and biocompatibility assessment" conducted. |
| Hybrid Tip Pointer Verification | "Hybrid Tip Pointer verification" conducted. |
| EMC and Electrical Safety | "EMC and electrical safety" conducted. |
| Cadaveric Design Validation | "Cadaveric Design Validation" conducted. |
| Overall Equivalence: | |
| Maintain intended use | "The software modifications being made do not impact the intended use or the fundamental technology of the device." |
| As safe and effective as predicate | "The subject device is also as safe and as effective as the predicate device and does not raise different questions of safety and effectiveness." |
2. Sample Size Used for the Test Set and Data Provenance
The document does not specify the sample sizes (e.g., number of cadavers for validation, number of units for software testing) or the data provenance (e.g., country of origin, retrospective/prospective). The testing listed is primarily non-clinical (lab-based, cadaveric, bench testing) to verify the device's functionality and safety modifications.
3. Number of Experts Used to Establish Ground Truth and Qualifications
This document describes a stereotaxic instrument for orthopedic surgery, not an AI/ML diagnostic or predictive model that requires expert annotation for ground truth. Therefore, the concept of "experts establishing ground truth" in the context of radiological image interpretation, for example, is not applicable here. Ground truth in this context would refer to precisely known anatomical landmarks or simulated bone cuts, which are inherent to the engineering and design validation processes of a surgical robot.
4. Adjudication Method for the Test Set
Adjudication methods (like 2+1, 3+1) are typically used for establishing ground truth in human-annotated datasets, particularly common in AI/ML diagnostic applications. Since this device is a surgical robotic system undergoing non-clinical technical validation, such adjudication methods are not relevant or mentioned. The validation would follow engineering testing protocols, where "ground truth" (e.g., accuracy of a cut relative to a plan) is measured by precise instruments or physical standards.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
No. The document does not mention any MRMC study. This type of study is primarily relevant for diagnostic AI tools where human readers (e.g., radiologists) interpret images with and without AI assistance to assess the AI's impact on their performance. The Mako Total Knee Application is a surgical assist system, and its validation focuses on the precision and safety of its robotic assistance, not on diagnostic reading improvement.
6. If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) Was Done
The device itself is a "human-in-the-loop" system, assisting the surgeon. The "Bone Registration and Resection Accuracy" and "Software Performance Verification" tests can be considered evaluations of the system's (algorithm + hardware) performance in a controlled environment, which includes the interaction of the software with the physical components. The document doesn't explicitly separate "algorithm only" performance for a non-diagnostic device. The system's performance is inherently tied to its function as an assistive tool to the surgeon.
7. The Type of Ground Truth Used
For the performance testing mentioned (e.g., "Bone Registration and Resection Accuracy," "Cadaveric Design Validation"), the ground truth would be established through:
- Precision Metrology: Highly accurate measurement equipment to verify the robotic arm's movements, resections, and landmark registrations against a pre-defined geometric plan or a physical standard.
- CT-based models: The system relies on CT data, so the "ground truth" for anatomical structures would be derived from these high-resolution imaging scans, verified by anatomical experts or engineering specifications.
- Controlled experimental setups: In cadaveric studies, the "ground truth" for ideal surgical outcomes (e.g., correct implant placement, precise bone cuts) would be defined by surgical and engineering standards and then measured on the cadaveric specimens post-procedure.
8. The Sample Size for the Training Set
This document describes a modification to an existing stereotaxic instrument, not a de novo AI/ML model that is "trained" on a dataset in the conventional sense. The "software changes" involve an update to the programming language, UI, features, and an optional planning tool (page 5). These are software updates to an existing system, rather than training a deep learning model. Therefore, the concept of a "training set" for an AI/ML algorithm isn't directly applicable as described here. The system likely uses fixed algorithms based on physics and geometry, possibly with some learned parameters from system calibration and empirical testing, but not in the framework of a large-scale data training process.
9. How the Ground Truth for the Training Set Was Established
As noted above, a "training set" in the context of AI/ML model development is not indicated for this device based on the document. The system's "ground truth" for its core functions (registration, resection guidance) would be established by fundamental engineering principles, anatomical studies, and precise metrology during its initial development and subsequent validation.
FDA 510(k) Clearance Letter - Mako Total Knee Application (3.0)
Page 1
U.S. Food & Drug Administration
10903 New Hampshire Avenue
Silver Spring, MD 20993
www.fda.gov
Doc ID # 04017.07.05
April 25, 2025
Mako Surgical Corp.
Shikha Khandelwal
Senior Principal Regulatory Affairs Specialist
3365 Enterprise Avenue
Weston, Florida 33331
Re: K250608
Trade/Device Name: Mako Total Knee Application (3.0); Hybrid Tip Pointer
Regulation Number: 21 CFR 882.4560
Regulation Name: Stereotaxic Instrument
Regulatory Class: Class II
Product Code: OLO
Dated: February 7, 2025
Received: February 28, 2025
Dear Shikha Khandelwal:
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 (the 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. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database available at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. 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.
Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device"
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K250608 - Shikha Khandelwal Page 2
(https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download).
Your device is also subject to, among other requirements, the Quality System (QS) regulation (21 CFR Part 820), which includes, but is not limited to, 21 CFR 820.30, Design controls; 21 CFR 820.90, Nonconforming product; and 21 CFR 820.100, Corrective and preventive action. Please note that regardless of whether a change requires premarket review, the QS regulation requires device manufacturers to review and approve changes to device design and production (21 CFR 820.30 and 21 CFR 820.70) and document changes and approvals in the device master record (21 CFR 820.181).
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 device-related adverse events) (21 CFR Part 803) for devices or postmarketing safety reporting (21 CFR Part 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reporting-combination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050.
All medical devices, including Class I and unclassified devices and combination product device constituent parts are required to be in compliance with the final Unique Device Identification System rule ("UDI Rule"). The UDI Rule requires, among other things, that a device bear a unique device identifier (UDI) on its label and package (21 CFR 801.20(a)) unless an exception or alternative applies (21 CFR 801.20(b)) and that the dates on the device label be formatted in accordance with 21 CFR 801.18. The UDI Rule (21 CFR 830.300(a) and 830.320(b)) also requires that certain information be submitted to the Global Unique Device Identification Database (GUDID) (21 CFR Part 830 Subpart E). For additional information on these requirements, please see the UDI System webpage at https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance/unique-device-identification-system-udi-system.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-devices/medical-device-safety/medical-device-reporting-mdr-how-report-medical-device-problems.
For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE
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K250608 - Shikha Khandelwal Page 3
by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely,
Shumaya Ali -S
Shumaya Ali, M.P.H.
Assistant Director
DHT6C: Division of Restorative,
Repair, and Trauma Devices
OHT6: Office of Orthopedic Devices
Office of Product Evaluation and Quality
Center for Devices and Radiological Health
Enclosure
Page 4
FORM FDA 3881 (6/20) Page 1 of 1 PSC Publishing Services (301) 443-6740 EF
DEPARTMENT OF HEALTH AND HUMAN SERVICES
Food and Drug Administration
Indications for Use
Form Approved: OMB No. 0910-0120
Expiration Date: 06/30/2023
See PRA Statement below.
510(k) Number (if known)
K250608
Device Name
Mako Total Knee Application (3.0)
Indications for Use (Describe)
The Mako System is intended to assist the surgeon in providing software defined spatial boundaries for orientation and reference information to anatomical structures during orthopedic procedures.
The Mako System is indicated for use in surgical knee procedures in which the use of stereotactic surgery may be appropriate, and where reference to rigid anatomical bony structures can be identified relative to a CT based model of the anatomy. These procedures include:
• Total Knee Arthroplasty (TKA)
The implant systems compatible with the system:
• Triathlon Total Knee System (CR/CS/PS/PSR cemented and cementless primary)
• Triathlon Total Knee System (TS inserts cemented primary)
Type of Use (Select one or both, as applicable)
☒ Prescription Use (Part 21 CFR 801 Subpart D) ☐ Over-The-Counter Use (21 CFR 801 Subpart C)
CONTINUE ON A SEPARATE PAGE IF NEEDED.
This section applies only to requirements of the Paperwork Reduction Act of 1995.
DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.
The burden time for this collection of information is estimated to average 79 hours per response, including the time to review instructions, search existing data sources, gather and maintain the data needed and complete and review the collection of information. Send comments regarding this burden estimate or any other aspect of this information collection, including suggestions for reducing this burden, to:
Department of Health and Human Services
Food and Drug Administration
Office of Chief Information Officer
Paperwork Reduction Act (PRA) Staff
PRAStaff@fda.hhs.gov
"An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB number."
DEPARTMENT OF HEALTH AND HUMAN SERVICES
Food and Drug Administration
Form Approved: OMB No. 0910-0120
Expiration Date: 06/30/2023
Indications for Use
See PRA Statement below.
510(k) Number (if known)
K250608
Device Name
Mako Total Knee Application (3.0)
Indications for Use (Describe)
The Mako System is intended to assist the surgeon in providing software defined spatial boundaries for orientation and reference information to anatomical structures during orthopedic procedures.
The Mako System is indicated for use in surgical knee procedures in which the use of stereotactic surgery may be appropriate, and where reference to rigid anatomical bony structures can be identified relative to a CT based model of the anatomy. These procedures include:
• Total Knee Arthroplasty (TKA)
The implant systems compatible with the system:
• Triathlon Total Knee System (CR/CS/PS/PSR cemented and cementless primary)
• Triathlon Total Knee System (TS inserts cemented primary)
Type of Use (Select one or both, as applicable)
☒ Prescription Use (Part 21 CFR 801 Subpart D) ☐ Over-The-Counter Use (21 CFR 801 Subpart C)
CONTINUE ON A SEPARATE PAGE IF NEEDED.
This section applies only to requirements of the Paperwork Reduction Act of 1995.
DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.
The burden time for this collection of information is estimated to average 79 hours per response, including the time to review instructions, search existing data sources, gather and maintain the data needed and complete and review the collection of information. Send comments regarding this burden estimate or any other aspect of this information collection, including suggestions for reducing this burden, to:
Department of Health and Human Services
Food and Drug Administration
Office of Chief Information Officer
Paperwork Reduction Act (PRA) Staff
PRAStaff@fda.hhs.gov
"An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB number."
FORM FDA 3881 (6/20) Page 1 of 1 PSC Publishing Services (301) 443-6740 EF
Page 5
510(k) SUMMARY – K250608
Sponsor: Mako Surgical Corp.
3365 Enterprise Ave
Weston, FL 33331
Contact Person: Shikha Khandelwal, PhD
Sr. Principal Regulatory Affairs Specialist
Shikha.Khandelwal@stryker.com
510-847-9264
Date Prepared: Feb 7, 2025
Proprietary Name: Mako Total Knee Application
Common Name: Total Knee Application (TKA)
Regulation Name: Stereotaxic Instrument
Regulation Number: 21 CFR Section 882.4560
Device Classification: Class II
Product Code: OLO
Substantial Equivalence Claimed To:
The subject device, the Mako Total Knee Application, is substantially equivalent to the predicate device, the Mako Total Knee Application, cleared in K241011.
Device Modifications:
Instrumentation: A new battery-powered active pointer is being introduced to support the registration, landmark selection and page selection workflow.
Software Changes: The Mako Total Knee Application is being modified to update the programming language, update the look of the user interface, enable additional features, add a new optional planning tool and enhance the overall user experience.
Labeling: Labeling provided with the device has been updated to reflect the proposed modifications.
510(k) SUMMARY – K250608
Sponsor: Mako Surgical Corp.
3365 Enterprise Ave
Weston, FL 33331
Contact Person: Shikha Khandelwal, PhD
Sr. Principal Regulatory Affairs Specialist
Shikha.Khandelwal@stryker.com
510-847-9264
Date Prepared: Feb 7, 2025
Proprietary Name: Mako Total Knee Application
Common Name: Total Knee Application (TKA)
Regulation Name: Stereotaxic Instrument
Regulation Number: 21 CFR Section 882.4560
Device Classification: Class II
Product Code: OLO
Substantial Equivalence Claimed To:
The subject device, the Mako Total Knee Application, is substantially equivalent to the predicate device, the Mako Total Knee Application, cleared in K241011.
Device Modifications:
Instrumentation: A new battery-powered active pointer is being introduced to support the registration, landmark selection and page selection workflow.
Software Changes: The Mako Total Knee Application is being modified to update the programming language, update the look of the user interface, enable additional features, add a new optional planning tool and enhance the overall user experience.
Labeling: Labeling provided with the device has been updated to reflect the proposed modifications.
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Description:
The Mako System with the subject Mako Total Knee Application is a stereotactic instrument that includes a robotic arm, an integrated cutting system, an optical detector, a camera, a computer, dedicated instrumentation, an operating software, and tools and accessories. The system's architecture is designed to support total and partial knee procedures and total hip procedures. With application specific hardware and software, the system provides haptic guidance during orthopedic surgical procedures by using patient CT data to assist a surgeon with pre-surgical planning, implant placement, and interpretive/intraoperative navigation of the patient's anatomy.
Once configured for a specific application, the Mako robotic arm can serve as the surgeon's "intelligent" tool holder or tool guide by passively constraining the preparation of an anatomical site for an orthopedic implant with software-defined spatial boundaries.
Summary of Technological Characteristics Compared to Predicate Device:
The technological characteristics of the Mako Total Knee Application compared to the predicate device are listed below:
| Technological Characteristics | Mako Total Knee Application | Mako Total Knee Application –K241011 |
|---|---|---|
| Major Components | Robotic arm, Stryker Q Guidance System, cutting system. | Robotic arm, Stryker Q Guidance System, cutting system. |
| Tools/accessories | Various reusable and disposable instruments | Various reusable and disposable instruments |
| Image Use | CT | CT |
Intended Use
The subject device has the same intended use as that specified in the cleared 510(k) premarket notification for the predicate device listed in this 510(k) premarket notification.
Indications for Use: Mako Total Knee Application
The Mako System is intended to assist the surgeon in providing software defined spatial boundaries for orientation and reference information to anatomical structures during orthopedic procedures.
The Mako System is indicated for use in surgical knee procedures in which the use of stereotactic surgery may be appropriate, and where reference to rigid anatomical bony structures can be identified relative to a CT based model of the anatomy. These procedures include:
Page 7
• Total Knee Arthroplasty (TKA)
The implant systems compatible with the system:
• Triathlon Total Knee System (CR/CS/PS/PSR cemented and cementless primary)
• Triathlon Total Knee System (TS inserts cemented primary)
Performance Data – The modified Mako System with the subject Mako Total Knee Application has been evaluated through the following non-clinical performance testing:
• Instrumentation cleaning, sterility, and biocompatibility assessment
• Hybrid Tip Pointer verification
• Software Functional Testing
• Software Performance Verification
• Bone Registration and Resection Accuracy
• Cadaveric Design Validation
• EMC and electrical safety
Conclusions:
The hardware and software of the subject Mako System with Mako Total Knee Application is equivalent to the hardware and software of the predicate Mako System with Mako Total Knee Application. The software modifications being made do not impact the intended use or the fundamental technology of the device. Furthermore, performance testing demonstrates that the characteristics of the subject Mako Total Knee Application are equivalent to the characteristics of the predicate device. The subject device is also as safe and as effective as the predicate device and does not raise different questions of safety and effectiveness. Therefore, performance testing supports a determination of substantial equivalence.
§ 882.4560 Stereotaxic instrument.
(a)
Identification. A stereotaxic instrument is a device consisting of a rigid frame with a calibrated guide mechanism for precisely positioning probes or other devices within a patient's brain, spinal cord, or other part of the nervous system.(b)
Classification. Class II (performance standards).