(60 days)
The Polaris Spinal System is a non-cervical spinal fixation device intended for immobilization and stabilization as an adjunct to fusion as a pedicle screw fixation system, a posterior hook and sacral/iliac screw fixation system, or as an anterior or anterolateral fixation system for use with autograft and/or allograft. The Polaris Spinal System is indicated for the following conditions: degenerative disc disease (defined as discogenic back pain with degeneration of the disc confirmed by history and radiographic studies), spondylolisthesis, trauma, (i.e., fracture or dislocation), deformity or curvature (i.e., scoliosis, kyphosis, Scheuermann's disease, and/or lordosis,), tumor, stenosis, pseudoarthrosis, or failed previous fusion.
The Ballista and Cypher MIS instruments are intended to be used with Ballista/ Cypher MIS /Polaris 5.5mm implants. Cannulated screws and percutaneous rods may be used with the Ballista/ Cypher MIS instruments to provide the surgeon with a percutaneous approach for posterior spinal surgery for the above indications.
For pediatric patients, the Polaris Spinal System may be used for posterior, non-cervical pedicle screw fixation as an adjunct to fusion to treat adolescent idiopathic scoliosis and is also indicated for treatment of the following conditions: spondylolysis and fractures caused by tumor and/or trauma. Pedicle screw fixation is limited to a posterior approach.
The Polaris Spinal System may be used with the instruments in the AccuVision Minimally Invasive Spinal Exposure System to provide the surgeon with a minimally invasive approach for posterior spinal surgery.
The dominos in the Polaris Spinal System can be used to connect the Polaris Spinal System to the Altius Spinal System, Lineum OCT Spine System, the Array Spinal System, the Biomet Omega21 Spinal System, or the Synergy Spinal System to achieve additional levels of fixation. Please refer to the individual system's Package Insert for a list of the indications for use for each system.
The Polaris Spinal System is a non-cervical spinal fixation device made from titanium alloy (Ti-6Al-4V) per ASTM F136, unalloyed titanium per ASTM F67, stainless steel per ASTM F138 or ASTM F1314 and Cobalt Chrome Alloy (Co-28Cr-6Mo) per ASTM F1537. The system includes screws, various types and sizes of rods, locking nuts, hooks, lateral connectors, plugs, fixation washers, rod connectors/dominos, various cross connectors and accessories. This submission is to update a contraindication related to the translation screws.
This document (K210275) is a 510(k) premarket notification for the Polaris Spinal System. It seeks clearance for a minor modification to the labeling related to a contraindication for translation screws, rather than a new device or significant design change requiring extensive performance studies.
Therefore, the typical battery of performance studies with large sample sizes, expert ground truth establishment, MRMC studies, and standalone algorithm performance evaluations are not applicable in this context.
The document explicitly states:
- "This submission is to update a contraindication related to the translation screws." (Page 3)
- "The purpose of this submission is to seek clearance for minor modifications to the labeling related to the translation screw." (Page 4)
- "No changes were made to any physical component of the Polaris Spinal System." (Page 5)
- "A risk assessment was conducted due to new information from a complaint. That risk assessment led to the inclusion of a contraindication to the labeling." (Page 5)
- "Per the FDA Guidance, The Special 510(k) Program, a Special 510(k) is appropriate when it is a change to the manufacturer's own device and performance data is not needed to evaluate the change." (Page 5)
- "Based on this information, the subject modifications do not raise any new issues regarding the safety or efficacy when compared to its predicates." (Page 5)
Given this, the requested information about acceptance criteria and detailed study designs (as they would apply to a new or significantly modified device) is not present in this 510(k) submission.
The "study" in this case was a risk assessment driven by a complaint, leading to a labeling change. It was not a performance study of the typical kind for a medical device.
Here's how to interpret the request in the context of this document:
1. A table of acceptance criteria and the reported device performance:
- Acceptance Criteria (Implied): The acceptance criteria for this specific submission revolved around ensuring that the updated labeling (including the new contraindication) adequately addressed the identified risk and maintained the device's substantial equivalence to its predicates without introducing new safety or efficacy concerns. Since no physical changes were made, mechanical performance or clinical outcomes were not re-evaluated.
- Reported Device Performance: Not applicable in the traditional sense of performance metrics (e.g., accuracy, sensitivity, specificity, computational speed). The "performance" here is that the risk assessment was completed, and the resulting contraindication was deemed appropriate to mitigate the identified risk.
2. Sample size used for the test set and the data provenance:
- Not applicable. There was no "test set" of clinical data for performance evaluation. The basis for the change was "new information from a complaint" (Page 5). This suggests a single or very limited number of reported adverse events or observations that triggered the re-evaluation of risk and subsequent labeling update.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not applicable. Ground truth for a performance study was not established. The "ground truth" for the labeling change was likely the outcome of an internal risk assessment by Zimmer Biomet's regulatory, engineering, and possibly clinical teams, based on the complaint information. The qualifications of these individuals are not detailed in the FDA letter.
4. Adjudication method for the test set:
- Not applicable. No test set requiring adjudication was used.
5. 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 device is a mechanical spinal fixation system, not an AI software.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Not applicable. This device is a mechanical spinal fixation system, not an algorithm.
7. The type of ground truth used:
- Not applicable for a performance study. The "ground truth" for the labeling change was the company's internal assessment of the risk associated with the translation screws, likely derived from post-market surveillance (a "complaint").
8. The sample size for the training set:
- Not applicable. No training set was used as this is not a learning algorithm.
9. How the ground truth for the training set was established:
- Not applicable. No training set was used.
§ 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.