(4 days)
The TOWNLEY Pedicle Screw Plating System is intended to stabilize the spine as an aid to fusion. After first making drill holes in the pedicles, a DYNA-LOK® plate is positioned of the pedicles. TOWNLEY Pedicle screws are then inserted through the DYNA-LOK® plate, down the center of the pedicles, and into the vertebral body. Bone graft must be used with each procedure.
This system is indicated for the treatment of any or all of the following at the C2 to S1 (inclusive) spinal levels: (a) Trauma, including spinal fractures and/or dislocations; (b) Spondylolisthesis; (c) Spondylolysis; (d) Pseudarthrosis or failed previous fusions which are symptomatic or which may cause secondary instability or deformity; (e) Degenerative disc disease and/or degenerative diseases which include: (1) degenerative disc disease (DDD) as defined by neck and/or back pain of discogenic origin as confirmed by radiographic studies; and/or (2) degenerative disease of the facets with instability.
This system consists of a broad-headed, partially threaded screw designed to compress bone grafts. Screw lengths range from 0.5 to 2.5 inches. Both cortical and cancellous screw threads are available. The screw comes in two configurations: flat-head or hex. The hex screws are wider in diameter. The stainless steel DYNA-LOK® plates are used to interconnect two or more vertebrae together via screw fixation through the pedicles. All components are fabricated from medical grade stainless steel (ASTM F-138 or its ISO equivalent). This 510(k) submission seeks to add 6.5mm diameter hex screws to the TOWNLEY Pedicle Screw Plating System.
This document describes the TOWNLEY Pedicle Screw Plating System, a medical device designed to stabilize the spine. It is a 510(k) summary submission, indicating that the manufacturer, Sofamor Danek, claims substantial equivalence to a predicate device already on the market.
Acceptance Criteria and Device Performance:
The document does not provide explicit acceptance criteria or a study demonstrating that the device meets such criteria. Instead, it details the device's description, indications for use, and a regulatory clearance letter from the FDA. The letter confirms "substantial equivalence" of the device system to previously marketed devices.
Table of Acceptance Criteria and Reported Device Performance:
Since this is a 510(k) submission and not a study reporting performance against specific acceptance criteria, such a table cannot be directly generated from the provided text. The regulatory process relies on demonstrating equivalence to existing legally marketed devices, rather than establishing de novo performance metrics. The closest to "reported device performance" is the FDA's acceptance of its substantial equivalence for the specified indications.
The following information cannot be extracted from the provided text:
- Sample size used for the test set and the data provenance: No test set is described.
- Number of experts used to establish the ground truth for the test set and the qualifications of those experts: No ground truth establishment for a test set is described.
- Adjudication method for the test set: No adjudication method is described.
- 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: No MRMC study or AI component is mentioned. This device is a mechanical implant, not an AI-assisted diagnostic or therapeutic tool.
- If a standalone (i.e. algorithm only without human-in-the-loop performance) was done: Not applicable as this is a medical implant, not an algorithm.
- The type of ground truth used: Not applicable as no specific study data or ground truth are discussed in relation to performance.
- The sample size for the training set: No training set is mentioned.
- How the ground truth for the training set was established: No training set is mentioned.
Summary of Device and Regulatory Clearance:
The TOWNLEY Pedicle Screw Plating System consists of broad-headed, partially threaded screws (ranging from 0.5 to 2.5 inches, with cortical and cancellous threads, and flat-head or hex configurations) and stainless steel DYNA-LOK® plates. The specific 510(k) submission seeks to add 6.5mm diameter hex screws to the existing system. All components are fabricated from medical grade stainless steel (ASTM F-138 or ISO equivalent).
Indications for Use (as cleared by FDA):
The system is intended to stabilize the spine as an aid to fusion, from C2 to S1 (inclusive) spinal levels. Bone graft must be used with each procedure.
The indications include:
- Trauma, including spinal fractures and/or dislocations.
- Spondylolisthesis (all grades and types).
- Spondylolysis.
- Pseudarthrosis or failed previous fusions which are symptomatic or may cause secondary instability or deformity.
- Degenerative disc disease and/or degenerative diseases, including:
- Degenerative Disc Disease (DDD) as defined by neck and/or back pain of discogenic origin (confirmed by radiographic studies).
- Degenerative disease of the facets with instability.
Substantial Equivalence:
The manufacturer submitted documentation asserting that the TOWNLEY Pedicle Screw Plating System is "substantially equivalent to itself," implying that the changes (addition of 6.5mm hex screws) do not alter the fundamental safety and effectiveness of the previously cleared system.
FDA Clearance (K982686):
The FDA reviewed the 510(k) submission and determined the device system is "substantially equivalent" for the stated indications. The FDA letter includes specific warnings and limitations on its use, emphasizing that pedicular screw fixation for other indications is considered investigational and requires an approved Premarket Approval (PMA) application. It also lists potential risks, including device component fracture, loss of fixation, non-union, vertebral fracture, neurological injury, and vascular or visceral injury.
§ 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.