The RetroFix screw is a cannulated tapered screw intended to be used as a stand-alone bone screw for internal bone fixation for bone fractures of the ankle.
Device Story
Cannulated tapered bone screw for internal fixation of ankle fractures. Device features proximal segment with large diameter, threaded distal segment, and flared end; cannula accommodates surgical K-wire. Used by surgeons in clinical settings for fracture stabilization. Device is non-sterile; requires sterilization prior to use. Provides mechanical support to bone fragments to facilitate healing. Benefits include stabilization of ankle fractures.
Clinical Evidence
No clinical tests performed. Evidence is based on bench testing of physical properties and biocompatibility assessment. Mechanical testing included static torsion, driving torque, removal torque, and static axial pullout (ASTM F543-17), and static/dynamic four-point bending strength (ASTM F1264-16).
Technological Characteristics
Cannulated tapered screw; material: 100% Ti-6AL-4V titanium alloy. Mechanical testing per ASTM F543-17 and ASTM F1264-16. Non-sterile; requires sterilization. No internal energy source. Accessories include stainless steel/titanium drill bits, depth gauge, drill guide, K-wire, and aluminum drive handle.
Indications for Use
Indicated for internal bone fixation of ankle fractures. Contraindicated in patients with allergies to stainless steel, nickel, or titanium; pediatric patients with open growth plates; ankle fractures with significant diastasis; active infection; conditions retarding healing (e.g., blood supply limitations); insufficient bone quality/quantity; malignant tumors; foreign-body sensitivity; or patients unable to follow post-operative weight-bearing restrictions.
Regulatory Classification
Identification
A smooth or threaded metallic bone fixation fastener is a device intended to be implanted that consists of a stiff wire segment or rod made of alloys, such as cobalt-chromium-molybdenum and stainless steel, and that may be smooth on the outside, fully or partially threaded, straight or U-shaped; and may be either blunt pointed, sharp pointed, or have a formed, slotted head on the end. It may be used for fixation of bone fractures, for bone reconstructions, as a guide pin for insertion of other implants, or it may be implanted through the skin so that a pulling force (traction) may be applied to the skeletal system.
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June 26, 2020
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Retrofix Screws, LLC % Keith A. Barritt Principal Fish & Richardson P.C. 1000 Maine Avenue, S.W. Suite 1000 Washington, District of Columbia 20024
Re: K200226
Trade/Device Name: RetroFix Regulation Number: 21 CFR 888.3040 Regulation Name: Smooth Or Threaded Metallic Bone Fixation Fastener Regulatory Class: Class II Product Code: HWC Dated: May 28, 2020 Received: May 29, 2020
Dear Keith Barritt:
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. 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 located 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.
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
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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 of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-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 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
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 https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-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/medicaldevices/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-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely,
Shumaya Ali, MPH 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
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#### DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration
## Indications for Use
510(k) Number (if known) K200226
Device Name Retrofix :
Indications for Use (Describe)
The RetroFix screw is a cannulated tapered screw intended to be used as stand-alone bone screw for internal bone fixation for bone fractures of the ankle.
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)
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# 510(k) Summary RetroFix Screws, LLC RETROFIX Bone Screw
#### Submitter
## (i) 510(k) Submitter
RetroFix Screws, LLC 1035 Lincolnton Road Salisbury, NC 28144
#### (ii) 510(k) Submitter Contact
Keith A. Barritt Fish & Richardson P.C. 1000 Maine Ave., S.W, Suite 1000 Washington, DC 20024 Phone: (202) 783-5070 Facsimile: (202) 783-2331 Email: barritt@fr.com
## (iii) Preparation Date
June 25, 2020
## Device
| Trade or Proprietary Name: | RetroFix |
|----------------------------|----------------------------------------------------|
| Common Name: | screw, fixation, bone |
| Classification Name: | smooth or threaded metallic bone fixation fastener |
| Product Code: | HWC, 21 CFR 888.3040 |
| Class: | 2 |
## Predicate Device
Arthrosurface Bone Screws predicate device (K#172383)
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#### Device Description
The RetroFix screw is a cannulated tapered screw intended to be used as a stand-alone bone screw for internal bone fixation for bone fractures of the ankle.
The device is contraindicated for:
- Patients with a history of allergy to stainless steel, nickel, or titanium
- Pediatric patients with open growth plates (epiphysis) ●
- Ankle fracture with significant diastasis (to be left to surgeon's judgement) ●
- Active Infection ●
- Conditions which tend to retard healing such as blood supply limitations ● or previous infections
- Insufficient quantity or quality of bone to permit stabilization of the fracture
- Cases with malignant primary or metastatic tumors which preclude . adequate bone support or screw fixations
- Foreign-body sensitivity ●
- Patients who cannot follow post-operative weight-bearing restrictions ●
The screw shaft has a predetermined length with a cannula extending through the length of the shaft. The shaft has a relatively large outside diameter proximal segment, a smaller outside diameter threaded distal segment, and a flared end.
The proximal segment and the distal segment are unitary. The cannula is adapted for use with a surgical K-wire. The screws have cortical threads and come in many different sizes, varying in diameter and lengths,
The device does not come sterile and must be sterilized prior to use.
## Indications for Use
The RetroFix screw is a cannulated tapered screw intended to be used as a stand-alone bone screw for internal bone fixation for bone fractures of the ankle.
## Comparison of Technological Characteristics
The RetroFix screw device has the same basic technological characteristics in terms of design, material, and chemical composition as the predicate device identified above. The RetroFix screw device does not have its own energy source.
A table comparing the two devices is shown below:
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| Device name | RetroFix Screw | Arthrosurface Bone Screws | Differences |
|--------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------|
| Manufacturer | RetroFix Scres, LLC | Arthrosurface, Inc. | |
| 510(K) No. | (Pending) | K172383 | |
| Device classification name | Smooth or threaded metallic bone fixation fastener | Smooth or threaded metallic bone fixation fastener | |
| Product code | HWC | HWC | |
| Indications for Use | The RetroFix screw is a cannulated tapered screw intended to be used as a stand-alone bone screw for internal bone fixation for bone fractures of the ankle. | The Arthrosurface Bone Screws (2.0-3.0 mm solid and cannulated) are intended to be used as stand-alone bone screws for internal bone fixation for bone fractures, fusions, osteotomies, and non-unions in the ankle, foot, hand, and wrist. | The scope of the indications for use of the RetroFix screw is within the scope of the predicate device's authorized Indications for Use. |
| | | The Arthrosurface Bone Screws (3.5 mm and larger, solid and cannulated) are intended to be used as stand-alone bone screws for internal bone fixation for bone fractures, fusions, osteotomies, and non-unions in the ankle, foot, hand, wrist, shoulder, clavicle, scapula, olecranon, humerus, radius, ulna, tibia, calcaneous, femur, and fibula. | |
| Principle of operation | Cannulated screws of various dimensions for bone fracture fixation | Cannulated screws of various dimensions for bone fracture fixation | |
| Material composition | RetroFix screws are 100% Ti-6AL-4V titanium alloy | Some screws are stainless steel and some are titanium alloy | |
| Device name | RetroFix Screw | Arthrosurface Bone Screws | Differences |
| | All accessories that come<br>into direct or indirect contact<br>with the patient (screw drive,<br>drill bits, depth gauge, drill<br>guide, and k-wire) are made<br>of stainless steel or titanium<br>(with the exception of the<br>drive handle which is made<br>of aluminum) | No accessories are identified<br>in the 510(k) Summary for<br>the Arthrosurface bone<br>screws | All accessories for the<br>RetroFix screws have<br>been assessed for<br>biocompatibility |
| Performance<br>Characteristics | The RetroFix screws were<br>tested pursuant to<br>ASTM F543 and ASTM<br>F1264 standards for<br>mechanical strength | The Arthosurface screws<br>were tested pursuant to<br>ASTM F543 standard for<br>mechanical strength | Both devices were<br>tested pursuant to<br>ASTM F543 |
## Comparison of RetroFix Screw device to Predicate Device
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## Shelf Life Testing
Shelf-life testing is not applicable because of the low likelihood of timedependent product degradation.
## Material And Chemical Composition
RetroFix screws are 100% Ti-6AL-4V titanium alloy.
#### Performance Data Summary
The RetroFix screw device was tested using ASTM F543-17 for static torsion, driving torque, removal torque, and static axial pullout, as well as ASTM F1264-16 for both static and dynamic four-point bending strength.
There were no clinical tests performed for the RetroFix screw device.
#### Conclusion
Based on the non-clinical testing conducted of the physical properties of the RetroFix screw device in comparison to the predicate device identified above, and on the biocompatibility assessment of the device, it is concluded that the RetroFix screw device is substantially equivalent to the predicate device.
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