(61 days)
The LEXUS Cervical Fixation System is indicated for the following:
- DDD (neck pain of discogenic origin with degeneration of the disc as confirmed by patient . history and radiographic studies)
- . Spondylolisthesis
- . Spinal stenosis
- . Fracture/dislocation
- . Failed previous fusion
- . Tumors
The implants are intended to provide stabilization as an adjunct to fusion when used with autogenous bone graft or allograft following the reduction of fractures/dislocations or trauma in the spine.
Hooks and rods are also intended to provide stabilization to promote fusion following reduction of fracture/dislocation or trauma in the cervical/upper thoracic (C1 -T3) spine.
The pedicle screws are limited to placement in T1 -T3 in treating thoracic conditions only. The pedicle screws are not intended to be placed in or treat conditions involving the cervical spine.
The purpose of this 510(k) submission is to add reduction polyaxial screws and curved rods. The LEXUS Cervical Spinal Fixation System is a top-loading, multiple component, posterior (cervical-thoracic) spinal fixation system which consists of polyaxial screws, reduction poly screws, straight rods, curved rods, set screws, and hooks.
Materials: All products are made of titanium alloy (Ti-6A1-4V ELI/ in conformance with ASTM F136) approved for medical use.
Here's an analysis of the provided text regarding the acceptance criteria and study for the LEXUS Cervical Fixation System:
This device (LEXUS Cervical Fixation System) is a Spinal Fixation System, and its "performance" is evaluated based on mechanical testing, not on parameters usually associated with AI/software devices (like sensitivity, specificity, or accuracy in diagnosing conditions). Therefore, many of the typical questions for AI medical devices (like expert adjudication, MRMC studies, training set details, etc.) are not applicable to this type of medical device submission.
The acceptance criteria here relate to the structural integrity and mechanical properties of the implants.
Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Performance Measure) | Reported Device Performance (Reference Standard) |
|---|---|
| Static Axial Compression Strength | Tested according to ASTM F1717 |
| Dynamic Axial Compression Strength | Tested according to ASTM F1717 |
| Static Tension Strength | Tested according to ASTM F1717 |
| Static Torsion Strength | Tested according to ASTM F1717 |
Explanation: The "acceptance criteria" for this physical device are the standards set by ASTM F1717 for spinal fixation systems. The "reported device performance" indicates that the device was tested against and found to meet these established standards. The submission asserts that because it meets these recognized consensus standards, it is substantially equivalent in safety and effectiveness to predicate devices.
Study Details
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Sample size used for the test set and the data provenance:
- Test Set Sample Size: Not explicitly stated in terms of a number of physical implants, but mechanical testing typically involves a sufficient number of samples to ensure statistical validity for the specific tests outlined in ASTM F1717.
- Data Provenance: The testing was conducted in the context of the manufacturer's submission for regulatory approval. The country of origin for the device manufacturer is South Korea. The study is prospective in the sense that the sponsor conducted the tests specifically for this submission.
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not Applicable. For a mechanical device, ground truth in terms of clinical diagnosis or interpretation by experts is not relevant. The "ground truth" for mechanical testing is established by the specifications and methodologies defined in the ASTM F1717 standard itself. The results are physical measurements, not expert interpretations.
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Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- Not Applicable. Adjudication methods are used for expert disagreements on qualitative assessments (e.g., image interpretation). This is a mechanical performance test.
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If a multi-reader multi-case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance:
- Not Applicable. This is not an AI/software device and does not involve human readers interpreting data.
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If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Not Applicable. This is a physical medical device, not an algorithm.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- The "ground truth" is adherence to the mechanical performance standards and methodologies specified by ASTM F1717. This includes physical properties like strength, stiffness, and resistance to fatigue under various loads, which are measured objectively.
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The sample size for the training set:
- Not Applicable. This is a hardware medical device, not a machine learning model; therefore, there is no "training set."
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How the ground truth for the training set was established:
- Not Applicable.
Summary of Device Performance Claim:
The L&K BIOMED LEXUS Cervical Fixation System's performance and safety are demonstrated by its compliance with internationally recognized mechanical testing standards (ASTM F1717). This standard evaluates static and dynamic axial compression, static tension, and static torsion. By meeting these benchmarks, the manufacturer asserts substantial equivalence to predicate devices, implying its safety and effectiveness for its intended use as a spinal fixation system.
§ 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.