The GMK® UNI knee prosthesis is designed for cemented use in partial knee arthroplasty, if there is evidence of sufficient sound bone to seat and support the components. Partial replacement of the articulating surfaces of the knee is indicated when only one side of the joint is affected due to the compartmental primary degenerative or post-traumatic degenerative disease, previous tibial condyle or plateau fractures, deformity or revision of previous arthroplasty.
Device Story
GMK UNI is a unicompartmental knee prosthesis for partial knee arthroplasty. System consists of a cemented cobalt-chromium-molybdenum (Co-Cr-Mo) femoral component, a fixed ultra-high molecular weight polyethylene (UHMWPE) tibial insert, and a metal-backed Co-Cr-Mo tibial tray. Implants are provided sterile for single use. Device is used by orthopedic surgeons in a clinical/surgical setting to replace articulating surfaces of the knee joint. By providing a stable, cemented interface, the device restores joint function and addresses degenerative disease or post-traumatic deformity. Clinical benefit is derived from the mechanical replacement of damaged joint surfaces, facilitating improved mobility and pain relief for the patient.
Clinical Evidence
Bench testing only. Studies included fatigue testing under dynamic physiological loads (ASTM F1800), excessive wear testing (ASTM F2083), sterilization validation (ANSI/AAMI/ISO 11137-1:2006, 11137-2:2006, ISO 11135-1:2007), accelerated and real-time aging, and packaging validation.
Technological Characteristics
Materials: Co-Cr-Mo (ISO 5832-4) for femoral/tibial tray; UHMWPE (ISO 5834-2 Type 1) for insert/plug. Design: Fixed-bearing, cemented, unicompartmental knee prosthesis. Stabilization: Femoral component (2 pegs); Tibial tray (peg and keel). Sterilization: Gamma irradiation or ethylene oxide. Connectivity: None (mechanical implant).
Indications for Use
Indicated for patients requiring partial knee arthroplasty due to compartmental primary degenerative or post-traumatic degenerative disease, previous tibial condyle or plateau fractures, deformity, or revision of previous arthroplasty, provided there is sufficient sound bone to seat and support components.
Regulatory Classification
Identification
A knee joint femorotibial metal/polymer non-constrained cemented prosthesis is a device intended to be implanted to replace part of a knee joint. The device limits minimally (less than normal anatomic constraints) translation in one or more planes. It has no linkage across-the-joint. This generic type of device includes prostheses that have a femoral condylar resurfacing component or components made of alloys, such as cobalt-chromium-molybdenum, and a tibial component or components made of ultra-high molecular weight polyethylene and are intended for use with bone cement (§ 888.3027).
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Image /page/0/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a circular border with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the edge. Inside the circle is an abstract symbol that resembles a stylized human figure or a bird in flight, composed of three overlapping profiles.
Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002
April 14, 2017
Medacta International SA Stefano Baj Regulatory Affairs Manager Strada Regina 6874 Castel San Pietro (CH) Switzerland
Re: K161741 Trade/Device Name: GMK UNI Regulation Number: 21 CFR 888.3520 Regulation Name: Knee Joint Femorotibial Metal/Polymer Non-Constrained Cemented Prosthesis Regulatory Class: Class II Product Code: HSX Dated: March 13, 2017 Received: March 14, 2017
Dear Stefano Baj:
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 devicerelated adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in
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the quality systems (OS) 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/ResourcesforYou/Industry/default.htm. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 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,
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)
K161741
Device Name GMK(R) UNI
#### Indications for Use (Describe)
The GMK(R) UNI knee prosthesis is designed for cemented use in partial knee arthroplasty, if there is evidence of sufficient sound bone to seat and support the components. Partial replacement of the articulating surfaces of the knee is indicated when only one side of the joint is affected due to the compartmental primary degenerative or post-traumatic degenerative disease, previous tibial condyle or plateau fractures, deformity or revision of previous arthroplasty.
| Type of Use (Select one or both, as applicable) | |
|---------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------|
| <div> <span> <span style="font-size:16px">☒</span> Prescription Use (Part 21 CFR 801 Subpart D) </span> </div> | <div> <span> <span style="font-size:16px">☐</span> Over-The-Counter Use (21 CFR 801 Subpart C) </span> </div> |
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Image /page/3/Picture/0 description: The image shows the logo for Medacta International. The logo consists of two blue triangles, followed by the word "Medacta" in blue. Underneath the word "Medacta" is a yellow line, and below that is the word "International" in blue, followed by a red and white Swiss flag.
#### 3 510(k) Summary
- Applicant/Sponsor: Medacta International SA Strada Regina 6874 Castel San Pietro (CH) Switzerland Phone (+41) 91 696 60 60 Fax (+41) 91 696 60 66
- Stefano Baj Contact Person: Regulatory Affairs Manager Phone: +41 91 696 60 60 Fax: +41 91 696 60 66 Email: baj@medacta.ch
- Date Prepared: June 17, 2016
# DEVICE INFORMATION
| Trade/Proprietary Name: | GMK® UNI |
|-------------------------|-------------------------------------------------------------------------------|
| Common or Usual Name: | Unicompartmental Knee prosthesis |
| Classification Name: | Knee joint femorotibial metal/polymer/ non-constrained cemented<br>prosthesis |
| Product Code: | HSX |
| Regulation Number: | 21 CFR 888.3520 |
| Device Class: | II |
## PREDICATE DEVICE INFORMATION
## Primary predicates:
| 510(k) | Product | 510(k) Holder |
|---------|---------|----------------|
| K073175 | Journey | Smith & Nephew |
## Additional predicates:
| 510(k) | Product | 510(k) Holder |
|---------|---------|----------------|
| K102069 | Journey | Smith & Nephew |
| K033363 | UNI | Zimmer |
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# DEVICE DESCRIPTION
The GMK® UNI is a unicompartmental knee prosthesis. The GMK® UNI is comprised of individually packaged femur and tibial components designed for cemented use in partial knee arthroplasty if there is evidence of sufficient sound bone to seat and support the components. The femoral component is made of cobalt-chromium-molybdenum (Co-Cr-Mo per ISO 5832-4), and the tibial component consists of an ultra-high molecular weight polyethylene (UHMWPE per ISO 5834-2 Type 1) insert, and a metal-backed tray component (Co-Cr-Mo per ISO 5832-4). The GMK® UNI system implants are offered sterile (via gamma irradiation or ethylene oxide), are intended for single use only, and may not be re-sterilized.
The Anatomic Femoral Component (cemented) is anatomically shaped and designed with two (2) fixation pegs. Available in six (6) sizes (0 - 5), the femoral component is offered in both Right Medial/Left Lateral (RM-LL) and Left Medial/Right Lateral (LM-RL) options for each size.
The Fixed Tibial Insert has a fixed design and is available in five (5) sizes (1 – 5). Each size is offered in six (6) levels of thickness (8, 9, 10, 11, 12, 14 mm).
The Fixed Plus Tibial Tray (cemented) has a fixed bearing design with one fixation keel and peg to ensure primary stability, and an UHMWPE plug. Available in five (5) sizes (1 – 5), the Fixed Plus Tibial Trays are offered in both Right Medial/Left Lateral (RM-LL) and Left Medial/Right Lateral (LM-RL) options for each size.
# INDICATIONS FOR USE
The GMK® UNI knee prosthesis is designed for cemented use in partial knee arthroplasty, if there is evidence of sufficient sound bone to seat and support the components. Partial replacement of the articulating surfaces of the knee is indicated when only one side of the joint is affected due to the compartmental primary degenerative or post-traumatic degenerative disease, previous tibial condyle or plateau fractures, deformity or revision of previous arthroplasty.
## Discussion:
The Indications for Use Statement is similar to the predicate device. The only difference is that the subject device calls out the requirements for "evidence of sufficient sound bone to seat and support the components", and the predicate device cites specific example of degenerative joint disease ("osteoarthritis, traumatic arthritis, or avascular necrosis"). These differences do not create new intended uses for the subject device; the subject and predicate devices are all prostheses intended for use in knee arthroplasty.
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# COMPARISON OF TECHNOLOGICAL CHARACTERISTICS
The design features, and materials of the subject devices are substantially equivalent to those of the predicate devices. The tables below compare characteristics of the subject and predicate devices.
| Feature | GMK UNI - Anatomic<br>Femoral Component<br>(cemented) | Smith & Nephew<br>Journey<br>(K073175) | Zimmer UNI<br>(K033363) |
|-----------------------|-----------------------------------------------------------------|---------------------------------------------------------|-------------------------|
| Sizes | 6 sizes (Size 0 - 5) | 7 sizes (Size 1 -7) | 7 sizes (Size A - G) |
| Configuration | RM-LL and LM-RL | Same | Same |
| Material | CoCrMo - ISO 5832-4 | Same<br>(with an oxinium oxidized<br>zirconium coating) | Same |
| Cemented? | Cemented | Same | Same |
| Device<br>Usage | Single Use | Same | Same |
| Sterility | Provided sterile via Gamma<br>Radiation | Same | Same |
| Shelf Life | 5 Years | Same | > 5 Years |
| Stabilization<br>pegs | Anatomic Femoral<br>component is cemented<br>with two (2) pegs. | Same | Same |
| Feature | GMK UNI - Fixed Tibial Insert | Zimmer UNI<br>(K033363) |
|-----------------|----------------------------------------------------------------------------|-------------------------|
| Sizes | 5 sizes (from 1 to 5) | 6 sizes (from 1 to 6) |
| Thickness | Each size is offered in 6 levels of thickness<br>(8, 9, 10, 11, 12, 14 mm) | Same |
| Material | UHMWPE (ISO 5834 -2) Type 1 | Same |
| Device<br>Usage | Single Use | Same |
| Sterility | Provided sterile via Ethylene Oxide | Same |
| Shelf Life | 5 years | > 5 years |
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| Feature | GMK UNI - Fixed Plus<br>Tibial Tray (cemented) | Smith & Nephew Journey<br>(K102069) | Zimmer UNI<br>(K033363) |
|-------------------|-------------------------------------------------------------|-------------------------------------|--------------------------------|
| Sizes | 5 sizes (from 1 to 5) | 6 sizes | 6 sizes (from 1 to 6) |
| Configurations | RM-LL and LM-RL | Same | Same |
| Material | CoCrMo (ISO 5832-4)<br>Plug: UHMWPE (ISO<br>5834 -2) Type 1 | Same | Ti-6Al-4V with PMMA<br>precoat |
| Cemented? | Cemented | Same | Same |
| Device Usage | Single Use | Same | Same |
| Sterility | Provided sterile via<br>Gamma Radiation | Unknown | Same |
| Shelf Life | 5 years | Unknown | > 5 years |
| Stabilization | Stabilized with peg and<br>keel | Same | Same |
| Fixed<br>Bearing? | Fixed bearing | Same | Same |
The fundamental scientific technology of the modified devices has not changed relative to the predicate devices. The safety and effectiveness of the subject devices is adequately supported by the substantial equivalence information, materials information, and analysis data provided within this Premarket Notification.
# PERFORMANCE TESTING
The following studies were performed to support substantial equivalence:
- Fatigue under dynamic physiological loads according to ASTM F1800 ●
- Excessive wear according to ASTM F2083 ●
- Sterilization validation in accordance with ANSI/AAMI/ISO 11137-1:2006, . ANSI/AAMI/ISO 11137-2:2006 and ISO 11135-1:2007
- · Accelerated and real time aging
- Packaging validation
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AWWWBased on the above information, the GMK® UNI can be considered substantially equivalent AWWW the identified predicate devices.
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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.