K Number
K202894
Date Cleared
2020-10-23

(25 days)

Product Code
Regulation Number
888.3070
Panel
OR
Reference & Predicate Devices
AI/MLSaMDIVD (In Vitro Diagnostic)TherapeuticDiagnosticis PCCP AuthorizedThirdpartyExpeditedreview
Intended Use

The Wiltrom Spinal Fixation 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 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; scoliosis; kyphosis; spinal tumor; and failed previous fusion (pseudarthrosis).

Device Description

The Wiltrom Spinal Fixation System is comprised of screws, rods, cross-link connector and associated surgical instruments that allow the surgeon to build an implant system to fit the patient's anatomical and physiological requirements. The Wiltrom Spinal Fixation System is designed to stabilize the vertebrae through a posterior approach. The Wiltrom spinal implants are made of Ti-6AI-4V ELI material which complies with ISO 5832-3 and ASTM F136. Wiltrom Spinal Fixation System is provided non-sterile, and the implants are for single use only.

AI/ML Overview

This document is a 510(k) Premarket Notification for a Wiltrom Spinal Fixation System. The provided text focuses on demonstrating the substantial equivalence of the subject device to a predicate device, primarily by showing that the proposed changes (updated surgical instruments) do not affect the safety and effectiveness of the spinal fixation system's core implants.

Therefore, the information you are asking for regarding acceptance criteria and a study proving device performance (like an AI/ML medical device where performance metrics are key) is not present in this document. This document is for a mechanical medical device, and its "performance data" refers to mechanical testing according to established ASTM standards, not clinical performance or diagnostic accuracy.

Here's why your request cannot be fulfilled by this document:

  • Type of Device: This is a Class II Thoracolumbosacral Pedicle Screw System (a mechanical implant), not a diagnostic device, imaging AI, or therapeutic software.
  • Approval Process: 510(k) clearance for this type of device relies heavily on demonstrating substantial equivalence to a legally marketed predicate device, often through design comparison, material testing, and mechanical performance testing to established standards (like ASTM F1717-15, as mentioned).
  • Nature of "Performance Data": For this device, "performance data" means the results of mechanical tests (static torsion, axial compression bending) to ensure the device can withstand physiological loads, not accuracy, sensitivity, or specificity as would be relevant for an AI/ML device.

Therefore, the sections below cannot be populated from the provided text, as the information is not relevant to this type of medical device submission.


Acceptance Criteria and Study for Wiltrom Spinal Fixation System (Based on provided text)

Based on the provided 510(k) summary for the Wiltrom Spinal Fixation System, the device is a mechanical implant (Thoracolumbosacral Pedicle Screw System). The "study that proves the device meets the acceptance criteria" for such a device primarily involves demonstrating substantial equivalence to an existing predicate device, backed by mechanical performance testing to established standards.

The concept of "acceptance criteria" and "study" as you've outlined involving human readers, AI assistance, ground truth establishment by experts, and specific clinical performance metrics (sensitivity, specificity, AUC) is typically applicable to diagnostic devices, particularly those incorporating AI/Machine Learning. It is not applicable to a mechanical spinal fixation system like the Wiltrom device based on the information provided in this 510(k) submission.

The "performance data" for this device, as stated in the document, refers to:

  • Mechanical testing in accordance with ASTM F1717-15.
  • Tests included: static torsion testing, static and dynamic axial compression bending testing.

The conclusion drawn from this testing is that "The performance of Wiltrom spinal implants in stabilizing the operative site and the mechanical safety was demonstrated, which is not affected by the proposed changes."

As such, I cannot provide the requested information in the format of AI/ML device performance. The provided document does not contain data on human reader studies, AI assistance, or expert ground truth adjudication for diagnostic purposes.

Specifically, for the points you asked for:

  1. A table of acceptance criteria and the reported device performance: Not applicable in the context of diagnostic performance metrics. The acceptance criteria here would be meeting the mechanical performance requirements of ASTM F1717-15, which are not detailed in terms of specific force or displacement values in this summary.
  2. Sample size used for the test set and the data provenance: Not applicable. There's no "test set" of patient data for diagnostic evaluation. Mechanical testing typically uses a specific number of devices per test, as per ASTM standards, but these details are not provided.
  3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts: Not applicable. There is no ground truth established by experts for diagnostic purposes.
  4. Adjudication method (e.g. 2+1, 3+1, none) for the test set: Not applicable.
  5. If a multi-reader multi-case (MRMC) comparative effectiveness study was done: Not applicable.
  6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done: Not applicable.
  7. The type of ground truth used (expert consensus, pathology, outcomes data, etc): Not applicable for diagnostic ground truth. The "ground truth" for this device is its mechanical integrity and ability to stabilize the spine, demonstrated through in vitro mechanical testing to established engineering standards.
  8. The sample size for the training set: Not applicable. This device does not involve a "training set" in the context of machine learning.
  9. How the ground truth for the training set was established: Not applicable.

§ 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.