The Wenzel Spine VariLift® Interbody Fusion System (VariLift®-A) is indicated for intervertebral body fusion of the lumbar spine, from L2 to S1, in skeletally mature patients who have had six months of non-operative treatment. The device is intended for use at either one level or two contiguous levels for the treatment of degenerative disc disease (DDD) with up to Grade I spondylolisthesis. DDD is defined as back pain of discogenic origin with degeneration of the disc confirmed by history and radiographic studies.

VariLift®-L is designed to be implanted bi-laterally via a posterior (PLIF) approach or as a single device via a transverse (TLIF) approach. VariLift®-A is designed to be implanted bi-laterally via an anterior (ALIF) approach. VariLift®-L and VariLift®-A may be implanted with or without supplemental fixation and is intended for use with autograft to facilitate fusion.

Device Description

The VariLift®-L Interbody Fusion Device may be implanted bi-laterally via a posterior lumbar (PLIF) approach or as a single device via a transverse (TLIF) approach. The VariLift®-L is a selftapping, expandable device with an interior sliding wedge and a posterior end cap. The devices are cylindrical-ovoid in shape, which is adapted to the general shape of the vertebral endplates. The VariLift®-L devices are made of titanium alloy (Ti6AI4V ELI per ASTM F136) and are provided sterile.

A design change was made on all sizes of the VariLift®-L devices to increase the surface in contact at the superior and inferior vertebrae. Additionally dimensional modification were made to the instrumentation to ensure all instruments work with all sizes of the modified devices.

AI/ML Overview

This document describes the regulatory submission for the VariLift®-L Interbody Fusion Device (K151900). It focuses on demonstrating substantial equivalence to a predicate device, primarily through non-clinical performance testing.

Here's an analysis of the acceptance criteria and study information provided:

1. Table of Acceptance Criteria and Reported Device Performance:

The document doesn't explicitly state numerical acceptance criteria in a table format. Instead, the acceptance criterion for the non-clinical tests is implicitly that the VariLift®-L Interbody Fusion Devices are "substantially equivalent" to the predicate devices in terms of mechanical performance.

Acceptance Criteria (Stated)	Reported Device Performance
Substantially equivalent to predicate devices in terms of mechanical performance (for static compression, shear, dynamic axial testing, subsidence testing, and expulsion testing).	"Demonstrated that the subject VariLift®-L Interbody Fusion Devices are substantially equivalent to predicate devices in terms of mechanical performance."

2. Sample Size Used for the Test Set and Data Provenance:

Sample Size: The document mentions that testing was conducted on "the smallest and longest of the new proposed sizes (10x28mm)" for additional device sizes and "the smallest and longest of the proposed new sizes (10x28mm)" for design modifications to existing sizes. It does not specify the exact number of devices tested for each type of test (e.g., how many 10x28mm devices were subjected to static compression).
Data Provenance: The studies are non-clinical performance tests, usually conducted in a laboratory setting. There is no mention of country of origin of data or whether it's retrospective or prospective, as these terms typically apply to clinical studies with human subjects.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications:

Not applicable. The tests are non-clinical mechanical performance studies, not clinical studies requiring expert interpretation of patient data or images to establish ground truth. The "ground truth" here is the physical measurement of mechanical properties according to established ASTM standards.

4. Adjudication Method for the Test Set:

Not applicable. This refers to the process of resolving discrepancies in expert opinions on ground truth in clinical or image-based studies. Mechanical testing relies on objective measurements.

5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study Was Done:

No. An MRMC study is a clinical study involving multiple human readers interpreting medical cases. The provided document describes non-clinical mechanical testing for device equivalence, not a clinical effectiveness study. Therefore, there's no information on how much human readers improve with AI vs. without AI assistance.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done:

Not applicable. This device is not an AI algorithm. It's an interbody fusion device, and the evaluation is mechanical performance.

7. The Type of Ground Truth Used:

The "ground truth" for the non-clinical tests is established by adhering to widely accepted mechanical testing standards from ASTM (e.g., ASTM 2077, ASTM F2267, ASTM Draft Standard F-04.25.02.02). These standards define how to objectively measure properties like static compression, shear, dynamic axial testing, subsidence, and expulsion forces.

8. The Sample Size for the Training Set:

Not applicable. This device does not involve a "training set" in the context of machine learning or AI models.

9. How the Ground Truth for the Training Set Was Established:

Not applicable, as there is no training set mentioned or implied for this device.

Summary

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Image /page/0/Picture/1 description: The image shows the seal of the Department of Health & Human Services - USA. The seal is circular and contains the words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the perimeter. In the center of the seal, there is a stylized image of three faces in profile, one behind the other.

Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002

December 11, 2015

Wenzel Spine, Incorporated Beckinam Nowatzke Director, Quality and Regulatory Affairs 206 Wild Basin Road, Building A, Suite 203 Austin, Texas 78746

Re: K151900

Trade/Device Name: VariLift®-L Interbody Fusion Device Regulation Number: 21 CFR 888.3080 Regulation Name: Intervertebral body fusion device Regulatory Class: Class II Product Code: MAX Dated: November 10, 2015 Received: November 12, 2015

Dear Ms. Nowatzke:

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 Parts 801); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set

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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/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/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 Statement

510(k) Number: K151900

Device Name: VariLift®-L Interbody Fusion Device

Indications for Use:

Prescription Use AND/OR Over-The-Counter Use

(Part 21 CFR 801 Subpart D) (21 CFR 807 Subpart C)

(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)

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510(k) Summary

Date Traditional 510(k) Prepared:	July 7, 2015
Trade Name:	VariLift®-L Interbody Fusion Device
Common Name:	Interbody Fusion Device (MAX)
Classification Name:	MAX 888.3080 - Intervertebral Fusion Device with BoneGraft, Lumbar
Submitted By:	Wenzel Spine, Inc.206 Wild Basin Road, Building A, Suite 203Austin, TX 78746
Contact Name:	Beckinam NowatzkeDirector, Quality & Regulatory AffairsPhone: 512-314-8271Fax: 512-469-0604

Predicate Device

VariLift®-L Interbody Fusion Device, K100820 (Primary Predicate). This predicate has not been subject to a design-related recall.

No reference devices were used in this submission.

Description of Device:

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Indications for Use:

Technical Characteristics:

The VariLift®-Lis a self-tapping, expandable Interbody Fusion Device with an interior sliding wedge and a posterior end cap. The device is grooved and fluted with large fenestrations (graft windows) positioned between each of the four quadrants that provide bony contact with the endplates.

Leqally Marketed Predicate Devices and Substantial Equivalence:

The proposed VariLift®-L Interbody Fusion Device is substantially equivalent to the primary predicate VariLift® L cleared as part of the VariLift® Interbody Fusion System (K100820, August 5, 2010) in terms of technology, design, and intended use. Additional predicate devices include down-classified cages and other cleared Interbody fusion devices such as the Brantigan Lumbar I/F Cage (P960025).

Summary of Non-Clinical Performance Testing:

Additional Device Sizes: Non-clinical testing was conducted on the smallest and longest of the new proposed sizes (10x28mm) to determine substantial equivalence to the primary predicate VariLift®-L smallest size (11x24mm). Static compression, shear, and dynamic axial testing (per ASTM 2077: "Test methods for Intervertebral Body Fusion Devices"), subsidence testing (per ASTM F2267: "Standard Test Method for Measuring Load Induced Subsidence of Intervertebral Body Fusion Device Under Static Axial Compression."), and expulsion testing (per ASTM Draft Standard F-04.25.02.02, "Static Push-out Test Method for Intervertebral Body Fusion Devices," Draft #2 - August 29, 2000) demonstrated that the subject VariLift®-L Interbody Fusion Devices are substantially equivalent to predicate devices in terms of mechanical performance.

Design Modifications to Existing Sizes: Non-clinical testing was conducted on the smallest and longest of the proposed new sizes (10x28mm) to determine substantial equivalence to the primary predicate VariLift®-L smallest size (11x24mm). Static compression, shear, and dynamic

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axial testing (per ASTM 2077: "Test methods for Intervertebral Body Fusion Devices"), subsidence testing (per ASTM F2267: "Standard Test Method for Measuring Load Induced Subsidence of Intervertebral Body Fusion Device Under Static Axial Compression."), and expulsion testing (per ASTM Draft Standard F-04.25.02.02, "Static Push-out Test Method for Intervertebral Body Fusion Devices," Draft #2 – August 29, 2000) demonstrated that the subject Varil_ift®-L Interbody Fusion Devices are substantially equivalent to predicate devices in terms of mechanical performance.

Design Modification to Instrumentation: Minor modifications to one of the VariLift®-L instruments were made to accommodate the TLIF approach. An engineering analysis was performed to confirm substantial equivalence to previously cleared instrumentation.

Conclusion:

The proposed VariLift® L Interbody Fusion Devices are substantially equivalent to the primary predicate VariLift® L Interbody Fusion Devices (K100820) in terms of intended use, indications for use, intervertebral body design and fundamental scientific technology.

Regulation Number and Section

§ 888.3080 Intervertebral body fusion device.

(a)
Identification. An intervertebral body fusion device is an implanted single or multiple component spinal device made from a variety of materials, including titanium and polymers. The device is inserted into the intervertebral body space of the cervical or lumbosacral spine, and is intended for intervertebral body fusion.(b)
Classification. (1) Class II (special controls) for intervertebral body fusion devices that contain bone grafting material. The special control is the FDA guidance document entitled “Class II Special Controls Guidance Document: Intervertebral Body Fusion Device.” See § 888.1(e) for the availability of this guidance document.(2) Class III (premarket approval) for intervertebral body fusion devices that include any therapeutic biologic (e.g., bone morphogenic protein). Intervertebral body fusion devices that contain any therapeutic biologic require premarket approval.
(c)
Date premarket approval application (PMA) or notice of product development protocol (PDP) is required. Devices described in paragraph (b)(2) of this section shall have an approved PMA or a declared completed PDP in effect before being placed in commercial distribution.