(44 days)
The Stowe Pedicle Screw 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 of thoracic, lumbar, and sacral spine: degenerative disc disease (DDD) (defined as back pain of discogenic origin with degeneration of the disc confirmed by history and radiographic studies); spondylolisthesis; trauma (i.e., fracture or dislocation); spinal stenosis; tumor; pseudoarthrosis; and failed previous fusion.
The STOWE Pedicle Screw System consists of longitudinal rods, polyaxial screws, and transverse connectors. It is manufactured from Ti-6Al-4V alloy conforming to ASTM F136.
Here's a breakdown of the requested information based on the provided text:
Important Note: The provided document is an FDA 510(k) clearance letter for a medical device (Stowe Pedicle Screw System), not a study report for an AI/ML powered device. Therefore, much of the requested information regarding acceptance criteria, performance studies, expert involvement, and ground truth for an AI/ML device is not present in this document. The document describes a traditional medical device and its substantial equivalence to a predicate device.
Acceptance Criteria and Study Information (Based on the Provided Document)
As this document pertains to a traditional medical device (spinal pedicle screw system) and not an AI/ML-powered one, the concepts of "acceptance criteria" and "study" as they relate to AI/ML performance (e.g., sensitivity, specificity, F1-score) are not applicable.
Instead, for this type of medical device, "acceptance criteria" would refer to demonstrating substantial equivalence to a previously cleared predicate device, typically through comparisons of:
- Intended Use
- Indications for Use
- Technological Characteristics (design, materials, dimensions)
- Performance (mechanical, biocompatibility, sterilization, etc. if changes warrant new testing)
The "study" that proves the device meets these criteria is a comparative analysis against the predicate device, often supported by engineering analysis, materials testing, and sometimes bench testing or animal studies if there are significant design changes. However, the document explicitly states:
"Performance data is not included in this submission. The design changes being included for review do not present a new worst-case configuration that would require additional performance testing."
This indicates that the "study" for this particular 510(k) relied primarily on the technical characteristics and equivalence to the predicate device rather than new, extensive performance data.
Here's an attempt to populate the table and answer the questions based on the document's context:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria Category | Specific Criteria (for traditional device equivalence) | Reported Device Performance (based on provided text) |
|---|---|---|
| Intended Use | Must be substantially equivalent to the predicate device. | Equivalent to ACME Talon Pedicle Screw System (K071824). |
| Indications for Use | Must be substantially equivalent to the predicate device for specified spinal conditions. | Equivalent to ACME Talon Pedicle Screw System (K071824). |
| Materials | Must be the same or substantially equivalent to the predicate device (e.g., Ti-6Al-4V alloy). | Manufactured from Ti-6Al-4V alloy conforming to ASTM F136; equivalent to predicate. |
| Technological Characteristics | Design (longitudinal rods, polyaxial screws, transverse connectors) must be substantially similar. | Equivalent to predicate device. No new worst-case configuration identified. |
| Performance Data | N/A (no new performance data required if no new worst-case configuration). | "Performance data is not included in this submission." |
| Labeling | Must be similar/equivalent and meet regulatory requirements. | Equivalent to predicate. |
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
- Sample Size: Not applicable. This is not a study involving patient data or an algorithm's test set. The "test set" here would refer to the device itself and its components, and the "testing" would be engineering analysis or bench testing. No specific sample sizes for such testing are detailed beyond the statement that no additional performance testing was required.
- Data Provenance: Not applicable.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Number of Experts: Not applicable. For this type of device submission, "ground truth" as it relates to clinical outcomes or image interpretation (which would require experts) is not the primary focus of the 510(k) for substantial equivalence. The expertise involved would be in engineering, materials science, and regulatory affairs to assess the device's design and compare it to the predicate.
- Qualifications of Experts: Not specified in the document, but would typically involve engineers and regulatory professionals at the manufacturing company and the FDA.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
- Adjudication Method: Not applicable. This term usually refers to resolving discrepancies in expert labeling or diagnoses for AI training/testing. For a traditional device, substantial equivalence is determined by regulatory review based on presented data and comparisons.
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
- MRMC Study: No. This type of study is relevant for AI-powered devices affecting human interpretation.
6. If a standalone (i.e. algorithm only without human-in-the loop performance) was done
- Standalone Performance: No. This is not an AI algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
- Type of Ground Truth: For this type of device, the "ground truth" for demonstrating safety and effectiveness is largely established by:
- Regulatory standards: Adherence to material specifications (e.g., ASTM F136).
- Predicate device's established safety and effectiveness: The historical performance and clearance of the ACME Talon Pedicle Screw System (K071824) serve as the benchmark.
- Engineering principles and biomechanical testing (if performed): To ensure the device performs as intended under expected loads. However, the document explicitly states no additional performance testing was needed for this submission.
8. The sample size for the training set
- Sample Size: Not applicable. This is not an AI/ML device requiring a training set.
9. How the ground truth for the training set was established
- Ground Truth Establishment: Not applicable. This is not an AI/ML device requiring a training set.
§ 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.