(74 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 ARX® Spinal System, when properly used, is intended for posterior pedicle screw fixation of the non-cervical posterior spine in skeletally mature patients. It provides stabilization and immobilization of spinal segments as an adjunct to fusion.
When used as a posterior spine thoracic/lumbar system, the ARX® 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, and/or lordosis), (4) spinal tumor, (5) failed previous fusion (6) pseudarthrosis, (7) spinal stenosis, (8) spondylolisthesis.
The ARX-Link™ Cross Connector is a titanium alloy, multiple component system comprised of a variety of non-sterile single use components that allow the surgeon to build a spinal implant construct. The system is attached to the vertebral body by means of screws to the non-cervical spine.
The ARX-Link [M Cross Connector is available in various sizes. This device is an addition to the current system (K061600) and therefore is fully cross-functional within the current system.
The ARX-Link™ Cross Connector is a medical device and its performance was evaluated through biomechanical testing. The information provided in the 510(k) summary (K070995) details the study conducted to demonstrate its substantial equivalence to previously cleared devices.
Acceptance Criteria and Reported Device Performance
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Mechanical integrity and stability as per ASTM F1717 standard for spinal implant constructs. | Biomechanical testing in accordance with ASTM F1717 was conducted. The study demonstrated that the ARX-Link™ Cross Connector met the requirements of the standard, thereby proving substantial equivalence in design, function, and materials to the predicate device (Life Spine ARX® Spinal Implant System K061600). |
Study Details
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Sample Size and Data Provenance:
- Test Set Sample Size: Not explicitly stated. For biomechanical testing of medical devices, the "sample size" typically refers to the number of test specimens (e.g., constructs with the ARX-Link™ Cross Connector) subjected to mechanical tests. The document only mentions that testing was "in accordance with ASTM F1717."
- Data Provenance: Not applicable in the context of device biomechanical testing, as the data is generated from laboratory experiments on device prototypes/samples, not human or patient data.
- Retrospective or Prospective: Not applicable for biomechanical testing.
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Number and Qualifications of Experts for Ground Truth:
- Not applicable. Ground truth for biomechanical testing is established by adherence to a recognized standard (ASTM F1717) and the physical properties/performance observed during the tests, not by expert interpretation of data like in clinical trials or image analysis.
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Adjudication Method for Test Set:
- Not applicable. Adjudication methods (like 2+1, 3+1) are typically used in clinical or imaging studies to reach consensus on difficult cases among multiple human readers. This is not relevant for objective biomechanical testing.
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Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
- No, an MRMC comparative effectiveness study was not done. This type of study is relevant for evaluating the impact of AI assistance on human reader performance, which is not applicable to a spinal implant system.
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Standalone Performance Study:
- Yes, a standalone study was conducted in the sense that the device's mechanical performance was tested independently against the ASTM F1717 standard. This is not an "algorithm-only" performance as the device is a physical implant. The testing evaluates the physical device itself.
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Type of Ground Truth Used:
- Standardized Biomechanical Testing Results: The ground truth is derived from the objective measurements and pass/fail criteria defined by the ASTM F1717 standard for spinal implant constructs. This standard specifies test methods for determining the mechanical characteristics of spinal implant assemblies.
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Training Set Sample Size:
- Not applicable. This device is a physical implant, not an AI or software algorithm that requires a "training set." The design and manufacturing process would involve engineering specifications, materials science, and prototyping, but not data "training" in the machine learning sense.
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How Ground Truth for Training Set Was Established:
- Not applicable. As noted above, there is no "training set" in the context of this physical medical device. The "ground truth" for the device's design and manufacturing is established through engineering principles, material specifications (e.g., ASTM F136 for medical grade titanium alloy), and quality control processes to ensure compliance with design intent and safety standards.
§ 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.