The Zavation Connector System is intended to provide immobilization of spinal segments in sketally mature patients as an adjunct to fusion in the treatment of the following acute and chronic instabilities of the craniocervical junction, the cervical spine (C1 to C7) and the thoracic spine (T1-T3): traumatic spinal fractures and/or traumatic dislocations; instability or deformity; failed previous fusions (e.g. pseudoarthrosis); tumors involving the cervical/thoracic spine; and degenerative disease, including intractable radior myelopathy, neck and/or arm pain of discogenic origin as confirmed by radiographic studies, and degenerative disease of the facets with instability.

When used with the Zavation Spinal System for Thoracic, Lumbar, and Sacral Spine Fixation (T1-S2/Illium)

The Zavation Connector System is intended to provide immobilization of spinal segments in sketally mature patients as an adjunct to fusion as a pedicle screw fixation system (T1-S2/Illium) in the treatment of the following acute and chronic instabilities or deformities of the thoracic, lumbar, and sacral spine: degenerative spondylolisthesis with objective evidence of neurological impairment, fracture, dislocation, scoliosis, spinal tumor, and failed previous fusion (pseudarthrosis).

Device Description

The Connector System is designed to aid in revision surgeries and extensions of existing hardware constructs from the Occiput to the Ilium. The Connector System includes a variety of non-sterile titanium implants including parallel rod to rod domino connectors, axial connectors with and without attachment rods, bypass connectors, lateral offsets, double tulips (angled and parallel), and Z rods. The implant options allow revisions and extension to be performed without removing existing hardware. The Zavation Connector System is designed to be used with the Zavation Z-Linkpc System for Posterior-Cervical-Thoracic (Occ-T3) and the Zavation Spinal System for Thoracic, Lumbar, and Sacral Spine Fixation (T1-S2/Illium).

AI/ML Overview

The provided text is a 510(k) summary for a medical device called the "Zavation Connector System." It details the device's purpose, description, indications for use, materials, and a comparison to predicate devices, along with performance data.

However, the provided text does not contain information about acceptance criteria, clinical studies involving human readers, expert ground truth establishment, sample sizes for training/test sets, or adjudication methods. The "Performance Data" section specifically states: "Static axial and torsional grip were performed according to ASTM F1798 on a worst-case construct. The mechanical test results demonstrated substantial equivalency to the predicate device." This indicates mechanical testing, not clinical performance studies involving human interpretation or AI assistance, which are the focus of your request.

Therefore, I cannot fulfill your request to describe the acceptance criteria and the study that proves the device meets them based on the provided document in the context of an AI/human reader performance study. The document describes the substantial equivalence of a physical medical implant (a pedicle screw system connector) based on mechanical properties, not an AI or imaging diagnostic device.

If this were a submission for an AI-powered diagnostic device, using the provided template, the description would approximate the following (hypothetical, as the actual data is not in the text):

Hypothetical Description of Acceptance Criteria and Study for an Imaginary AI-Powered Spinal Bone Fracture Detection Device (Not from the provided text)

Based on the provided document, the device in question is the "Zavation Connector System," which is a mechanical implant (thoracolumbosacral pedicle screw system) used to immobilize spinal segments. The provided performance data relates to static axial and torsional grip mechanical testing according to ASTM F1798, demonstrating substantial equivalence to a predicate device in terms of its physical properties and function, not its diagnostic accuracy or the performance of an AI algorithm.

Therefore, the detailed information requested regarding acceptance criteria, study sample sizes, expert ground truth establishment, MRMC studies, and AI performance metrics is not present in the provided 510(k) summary for the Zavation Connector System. This type of information is typically required for diagnostic imaging devices, especially those incorporating AI.

However, to illustrate how such a request would be addressed if the provided document were about an AI-powered diagnostic device, I will provide a hypothetical response demonstrating the structure and type of information that would be present.

Hypothetical Scenario: Acceptance Criteria and Study for an AI-Powered Spinal Bone Fracture Detection Device

Device Name (Hypothetical): SpinalFractureAI Assistant

Indications for Use (Hypothetical): The SpinalFractureAI Assistant is intended as a supplemental tool for radiologists to detect and localize vertebral fractures in thoracic and lumbar spine CT scans in adult patients.

1. Table of Acceptance Criteria and Reported Device Performance:

Performance Metric	Acceptance Criteria (Pre-defined)	Reported Device Performance (Hypothetical)
Sensitivity	≥ 80% (standalone)	85.2%
Specificity	≥ 75% (standalone)	78.9%
F1-Score	≥ 80% (standalone, fracture localization)	82.1%
Radiologist Reading Time	< 10% increase vs. without AI assistance	8% decrease (compared to without AI)
Radiologist Sensitivity (with AI)	≥ 5 percentage points improvement over without AI	7.2 percentage points improvement
Radiologist Specificity (with AI)	No significant decrease (p > 0.05) over without AI	No significant decrease (p=0.12)

2. Sample Sizes and Data Provenance:

Test Set Sample Size: 500 unique CT scans (patients).
Data Provenance: Retrospective data collected from 3 major hospital systems across the United States (n=300), Germany (n=100), and Japan (n=100).
Data Type: De-identified thoracic and lumbar spine CT scans.

3. Number of Experts for Ground Truth and Qualifications:

Number of Experts: 3 independent expert radiologists.
Qualifications: All were board-certified radiologists with subspecialty training in musculoskeletal radiology, each possessing at least 10 years of experience interpreting spinal CT scans.

4. Adjudication Method for the Test Set:

Adjudication Method: 2+1 Consensus. Initial reads by two independent expert radiologists. In cases of disagreement on the presence or location of a fracture, a third, senior-level expert radiologist reviewed the case to establish the definitive ground truth.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:

Yes, an MRMC comparative effectiveness study was performed.
Effect Size: Human readers (radiologists) demonstrated a 7.2 percentage point improvement in fracture detection sensitivity when assisted by the AI algorithm compared to reading without AI assistance. This was statistically significant (p < 0.001). There was no significant impact on specificity.

6. Standalone (Algorithm Only) Performance:

Yes, standalone performance was evaluated.
Metrics: Sensitivity: 85.2%, Specificity: 78.9%, F1-Score: 82.1% for fracture localization.

7. Type of Ground Truth Used:

Expert Consensus: The primary ground truth for fracture presence and location was established by the consensus of three expert radiologists, as described in point 4.
Supporting Data (for some cases): In a subset of ambiguous cases, available clinical follow-up data (e.g., subsequent imaging, clinical notes, or surgical reports confirming fracture presence/absence) was consulted to reinforce the expert consensus.

8. Sample Size for the Training Set:

Training Set Sample Size: 8,000 unique annotated CT scans (patients).
Validation Set Sample Size: 1,000 unique annotated CT scans (patients), separate from the training and test sets.

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

Initial Annotation: Trained clinical annotators, supervised by a radiologist, performed initial labeling of fractures based on established radiological criteria.
Radiologist Review & Correction: All annotations were then reviewed and corrected by a team of 5 board-certified general radiologists (not necessarily subspecialists) with 3-7 years of experience.
Quality Control: A subset (10%) of the annotated training data was randomly selected and re-reviewed by a senior radiologist (different from the experts in the test set ground truth team) to ensure consistency and quality. Iterative refinement and correction cycles were performed until an acceptable level of inter-reader agreement was achieved.

Summary

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August 22, 2023

Image /page/0/Picture/1 description: The image shows the logo of the U.S. Food and Drug Administration (FDA). The logo consists of two parts: the Department of Health & Human Services logo on the left and the FDA logo on the right. The FDA logo is in blue and includes the letters "FDA" in a square, followed by the words "U.S. FOOD & DRUG" and "ADMINISTRATION".

Zavation Medical Products, LLC Noah Slack Engineer 3670 Flowood Dr. Flowood, Mississippi 39232

Re: K231811

Trade/Device Name: Zavation Connector System Regulation Number: 21 CFR 888.3070 Regulation Name: Thoracolumbosacral Pedicle Screw System Regulatory Class: Class II Product Code: NKB, KWQ, NKG, KWP Dated: June 16, 2023 Received: June 21, 2023

Dear Noah Slack:

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 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

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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.

Digitally signed Eileen by Eileen Cadel -Cadel -S Date: 2023.08.22 for 10:10:03 -04'00'

Colin O'Neill, M.B.E. Assistant Director DHT6B: Division of Spinal Devices OHT6: Office of Orthopedic Devices Office of Product Evaluation and Quality Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known) K231811

Device Name Zavation Connector System

Indications for Use (Describe) When used with the Zavation ZLinkPC System for Posterior-Cervical-Thoracic (Occ-T3)

When used with the Zavation Spinal System for Thoracic, Lumbar, and Sacral Spine Fixation (T1-S2/Illium)

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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K231811 Page 1 of 3

510K Summary

Date:	June 16, 2023
Submitter:	Zavation Medical Products, LLC3670 Flowood DriveFlowood, MS 39232Phone: 601-919-1119Fax: 800-447-1302
Contact person:	Noah Slack
Type of 510(k) submission:	Traditional
Trade name:	Zavation Connector System
Common name:	Connector System
Classification regulation:	Thoracolumbosacral Pedicle Screw System, 21 CFR 888.3070 (NKB)Spinal Intervertebral Body Fixation Orthosis, 21 CFR 888.3060 (KWQ)Posterior Cervical Screw System, 21 CFR 888.3075 (NKG)Appliance, Fixation, Spinal Interlaminal, 21 CFR 888.3050 (KWP)
Device classification:	Class II
Classification Panel:	Orthopedic
Product code:	NKG, KWP, NKB, KWQ
Basis for submission:	New Device

Purpose: The purpose of this submission is to request clearance for Zavation Connector System instruments and implants.

Device Description: The Connector System is designed to aid in revision surgeries and extensions of existing hardware constructs from the Occiput to the Ilium. The Connector System includes a variety of non-sterile titanium implants including parallel rod to rod domino connectors, axial connectors with and without attachment rods, bypass connectors, lateral offsets, double tulips (angled and parallel), and Z rods. The implant options allow revisions and extension to be performed without removing existing hardware. The Zavation Connector System is designed to be used with the Zavation Z-Linkpc System for Posterior-Cervical-Thoracic (Occ-T3) and the Zavation Spinal System for Thoracic, Lumbar, and Sacral Spine Fixation (T1-S2/Illium).

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Indications for Use:

When used with the Zavation ZLinkPC System for Posterior-Cervical-Thoracic (Occ-T3)

The Zavation Connector System is intended to provide immobilization of spinal segments in skeletally mature patients as an adjunct to fusion in the treatment of the following acute and chronic instabilities of the craniocervical junction, the cervical spine (C1 to C7) and the thoracic spine (T1-T3): traumatic spinal fractures and/or traumatic dislocations; instability or deformity; failed previous fusions (e.g. pseudoarthrosis); tumors involving the cervical/thoracic spine; and degenerative disease, including intractable radiculopathy and/or myelopathy, neck and/or arm pain of discogenic origin as confirmed by radiographic studies, and degenerative disease of the facets with instability.

When used with the Zavation Spinal System for Thoracic, Lumbar, and Sacral Spine Fixation (T1-S2/Illium)

The Zavation Connector System is intended to provide immobilization of spinal segments in skeletally mature patients as an adjunct to fusion as a pedicle screw fixation system (T1-S2/Illium) in the treatment of the following acute and chronic instabilities or deformities of the thoracic, lumbar, and sacral spine: degenerative spondylolisthesis with objective evidence of neurological impairment, fracture, dislocation, scoliosis, spinal tumor, and failed previous fusion (pseudarthrosis).

Materials:

The Zavation Connector System components are manufactured from titanium alloy (Ti-6Al-4V) as described by ASTM F136.

Primary Predicate Device:

K170647 Connector System [Orthofix]

Additional Predicate Devices:

K222614 Zavation Modular System [Zavation] K112484 Zavation Spinal System [Zavation] K162575 Zavation Z-Linkçc System [Zavation]

Performance Data:

Static axial and torsional grip were performed according to ASTM F1798 on a worst-case construct. The mechanical test results demonstrated substantial equivalency to the predicate device.

Comparison of Technological Characteristics:

The Zavation Connector System possesses the same technological characteristics as the predicate devices. These include: basic design and dimensions, material (titanium alloy), mechanical safety and performances, and intended use (as described above).

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K231811 Page 3 of 3

Substantial Equivalence Conclusion:

The Zavation Connector System devices are similar to the predicate systems with respect to technical characteristics, performance and intended use. The information provided within this premarket notification supports substantial equivalence of the subject device to the predicate devices.

Regulation Number and Section

§ 888.3070 Thoracolumbosacral pedicle screw system.

(a)
Identification. (1) Rigid pedicle screw systems are comprised of multiple components, made from a variety of materials that allow the surgeon to build an implant system to fit the patient's anatomical and physiological requirements. Such a spinal implant assembly consists of a combination of screws, longitudinal members (e.g., plates, rods including dual diameter rods, plate/rod combinations), transverse or cross connectors, and interconnection mechanisms (e.g., rod-to-rod connectors, offset connectors).(2) Semi-rigid systems are defined as systems that contain one or more of the following features (including but not limited to): Non-uniform longitudinal elements, or features that allow more motion or flexibility compared to rigid systems.
(b)
Classification. (1) Class II (special controls), when intended to provide immobilization and stabilization of spinal segments in skeletally mature patients as an adjunct to fusion in the treatment of the following acute and chronic instabilities or deformities of the thoracic, lumbar, and sacral spine: severe spondylolisthesis (grades 3 and 4) of the L5-S1 vertebra; degenerative spondylolisthesis with objective evidence of neurologic impairment; fracture; dislocation; scoliosis; kyphosis; spinal tumor; and failed previous fusion (pseudarthrosis). These pedicle screw spinal systems must comply with the following special controls:(i) Compliance with material standards;
(ii) Compliance with mechanical testing standards;
(iii) Compliance with biocompatibility standards; and
(iv) Labeling that contains these two statements in addition to other appropriate labeling information:
“Warning: The safety and effectiveness of pedicle screw spinal systems have been established only for spinal conditions with significant mechanical instability or deformity requiring fusion with instrumentation. These conditions are significant mechanical instability or deformity of the thoracic, lumbar, and sacral spine secondary to severe spondylolisthesis (grades 3 and 4) of the L5-S1 vertebra, degenerative spondylolisthesis with objective evidence of neurologic impairment, fracture, dislocation, scoliosis, kyphosis, spinal tumor, and failed previous fusion (pseudarthrosis). The safety and effectiveness of these devices for any other conditions are unknown.”
“Precaution: The implantation of pedicle screw spinal systems should be performed only by experienced spinal surgeons with specific training in the use of this pedicle screw spinal system because this is a technically demanding procedure presenting a risk of serious injury to the patient.”
(2) Class II (special controls), when a rigid pedicle screw system is intended to provide immobilization and stabilization of spinal segments in the thoracic, lumbar, and sacral spine as an adjunct to fusion in the treatment of degenerative disc disease and spondylolisthesis other than either severe spondylolisthesis (grades 3 and 4) at L5-S1 or degenerative spondylolisthesis with objective evidence of neurologic impairment. These pedicle screw systems must comply with the following special controls:
(i) The design characteristics of the device, including engineering schematics, must ensure that the geometry and material composition are consistent with the intended use.
(ii) Non-clinical performance testing must demonstrate the mechanical function and durability of the implant.
(iii) Device components must be demonstrated to be biocompatible.
(iv) Validation testing must demonstrate the cleanliness and sterility of, or the ability to clean and sterilize, the device components and device-specific instruments.
(v) Labeling must include the following:
(A) A clear description of the technological features of the device including identification of device materials and the principles of device operation;
(B) Intended use and indications for use, including levels of fixation;
(C) Identification of magnetic resonance (MR) compatibility status;
(D) Cleaning and sterilization instructions for devices and instruments that are provided non-sterile to the end user; and
(E) Detailed instructions of each surgical step, including device removal.
(3) Class II (special controls), when a semi-rigid system is intended to provide immobilization and stabilization of spinal segments in the thoracic, lumbar, and sacral spine as an adjunct to fusion for any indication. In addition to complying with the special controls in paragraphs (b)(2)(i) through (v) of this section, these pedicle screw systems must comply with the following special controls:
(i) Demonstration that clinical performance characteristics of the device support the intended use of the product, including assessment of fusion compared to a clinically acceptable fusion rate.
(ii) Semi-rigid systems marketed prior to the effective date of this reclassification must submit an amendment to their previously cleared premarket notification (510(k)) demonstrating compliance with the special controls in paragraphs (b)(2)(i) through (v) and paragraph (b)(3)(i) of this section.