(70 days)
Internal fixation implants are load-sharing devices intended to stabilize and maintain alignment until normal healing occurs. Implants are not intended to replace normal body structures or bear the weight of the body in the presence of incomplete bone healing.
The NAUTILUS Thoracolumbar Spinal System, when properly used, is intended for posterior pedicle screw fixation of the non-cervical posterior spine in skeletally mature patients and for pediatric patients to treat adolescent idiopathic scoliosis (4.75 systems only). It provides stabilization and immobilization of spinal segments as an adjunct to fusion. Pediatric pedicle screw fixation is limited to a posterior approach.
When used as a posterior spine thoracic/lumbar system, the NAUTILUS Thoracolumbar Spinal System is indicated for one or more of the following: (1) degenerative disc disease (is defined as back pain of discogenic origin with degeneration of the disc confirmed by history and radiographic studies), (2) trauma (i.e. fracture or dislocation), (3) curvatures (scoliosis, kyphosis, and/or lordosis), (4) spinal tumor, (5) failed previous fusion (6) pseudarthrosis, (7) spinal stenosis, (8) spondylolisthesis.
In order to achieve additional levels of fixation in skeletally mature patients, the NAUTILUS Thoracolumbar Spinal System 5.5 rod system may be connected to the Solstice-OccipitoCervicoThoracic Fixation System's 3.5mm rod.
The NAUTILUS Thoracolumbar Spinal System consists of an assortment of rods, screws, cross connectors, and axial and offset connectors. The bone screw, head, and taper lock are assembled together during manufacturing to create the NAUTILUS Thoracolumbar Spinal System screw assembly component. The cross, axial, and offset connectors are also assembled during manufacturing. The NAUTILUS Thoracolumbar Spinal System implant components are made from titanium alloy (Ti-6AI-4V ELI) as described by ASTM F136 and cobalt chrome per ASTM 1537. Do not use any of the NAUTILUS Thoracolumbar Spinal System components with the components from any other system or manufacturer.
The purpose of this submission is to add new screw iterations to the Nautilus Spinal System.
This document pertains to the Nautilus Spinal System, a medical device intended for spinal fixation, and is a 510(k) premarket notification. It describes the device, its intended use, and claims substantial equivalence to previously marketed predicate devices.Acceptance Criteria and Device Performance for Nautilus Spinal System (K151196)
This 510(k) submission for the Nautilus Spinal System does not describe an AI/algorithm-based device and therefore does not have acceptance criteria or a study proving that an algorithm meets such criteria. Instead, it is for a physical medical device (spinal fixation system) and relies on mechanical testing to demonstrate substantial equivalence to predicate devices.
However, based on the provided text, we can extrapolate the performance data mentioned for the physical device as meeting implied acceptance criteria related to mechanical integrity and safety.
Here's an interpretation based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Implied) | Reported Device Performance (as per document) |
|---|---|
| Mechanical Strength and Durability | "Mechanical testing was included to demonstrate the substantial equivalency of the Nautilus Spinal System. The testing included static and dynamic compression and static torsion testing per ASTM F1717 as well as static axial grip, torsional grip and moment bending per ASTM F1798." |
| Biocompatibility of Materials | "The NAUTILUS Spinal System is 6AL-4V-ELI titanium manufactured according to ASTM F136 and cobalt chrome per ASTM 1537." (This implies the materials meet established standards for biocompatibility in implantable devices). |
| Device Configuration and Functional Equivalence | "The Nautilus Spinal System is substantially equivalent to the predicate system in terms of design, materials, indications for use and sizing." (This statement is the core claim of a 510(k) and implies the physical device functions equivalently to existing, legally marketed devices.) |
| Safety and Effectiveness (Implied by substantial equivalence) | The FDA's substantial equivalence determination ("we have determined the device is substantially equivalent... to legally marketed predicate devices") indicates that the device is considered as safe and effective as predicate devices that already exist on the market. The mechanical testing cited above supports this claim by demonstrating performance comparable to the predicates against recognized standards. |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: Not explicitly stated as a number of devices or iterations. The testing involved various "screw iterations" and system components. The tests (static/dynamic compression, torsion, axial grip, torsional grip, moment bending) would have been performed on a sufficient number of samples of the Nautilus Spinal System components to satisfy the requirements of ASTM F1717 and ASTM F1798.
- Data Provenance: The document does not specify the origin (e.g., country) of the data, but it would have been generated in a controlled laboratory setting (likely in the US or a country with recognized testing standards). The study is prospective in the sense that the testing was conducted specifically for this submission to demonstrate the performance of the new device.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
- This question is not applicable as the Nautilus Spinal System is a physical medical device, not an AI/algorithm. "Ground truth" in this context would refer to the physical and mechanical properties being measured by established testing methodologies rather than expert consensus on data interpretation. The "experts" involved would be engineers and lab technicians conducting the mechanical tests according to ASTM standards.
4. Adjudication Method for the Test Set
- This question is not applicable. Mechanical testing results are objective measurements (e.g., force, displacement, torque) against pre-defined engineering standards (ASTM F1717, ASTM F1798), not subjective interpretations requiring adjudication.
5. If a multi-reader multi-case (MRMC) comparative effectiveness study was done
- This question is not applicable. An MRMC study is relevant for diagnostic imaging AI algorithms where human readers interpret medical images. This submission is for a physical spinal implant system.
6. If a standalone (i.e. algorithm only without human-in-the loop performance) was done
- This question is not applicable. There is no algorithm described in this submission.
7. The type of ground truth used
- The "ground truth" for the performance of the Nautilus Spinal System is its mechanical properties as measured by standardized engineering tests (ASTM F1717 and ASTM F1798). These standards define the methods and expected performance characteristics for spinal implant devices. The "truth" is whether the device meets or exceeds the mechanical performance requirements outlined by these standards, indicating its structural integrity and comparability to predicate devices.
8. The sample size for the training set
- This question is not applicable. There is no algorithm or "training set" in the context of this device submission.
9. How the ground truth for the training set was established
- This question is not applicable. There is no algorithm or "training set" in the context of this device submission.
§ 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.