(21 days)
The Titanium MX Plate Based Low Back System is intended for use in Grade 3 and 4 spondylolisthesis at L5-S1, when affixed to the lumbosacral spine, utilizing autologous bone graft, and intended to be removed after solid fusion is attained. Levels of attachment for this indication range from L3 to the sacrum.
The TiMX Plate Based Low Back System is a variation of the existing titanium alloy VSP Spinal System previously cleared under K944736. The TiMX Plate Based Low Back System is a construct that consists of pedicle and sacral screws, spine plates, nuts, washers and a transverse connector. This modified system provides increased pedicle screw strength, increased construct fatigue performance, increased construct stiffness, improved geometry and lower profile than its predecessor, the titanium alloy VSP Spinal System.
The document describes a medical device called the "TiMX Plate Based Low Back System" and its substantial equivalence to a previously cleared device. It is a 510(k) premarket notification, which assesses substantial equivalence to a predicate device rather than establishing new acceptance criteria and conducting studies to prove the device meets those criteria from scratch.
Therefore, the information you're requesting regarding "acceptance criteria" and a "study that proves the device meets the acceptance criteria" in the context of typical AI/software device evaluation (e.g., sensitivity, specificity, F1-score) is not directly applicable to this type of medical device submission.
Instead, the document details performance data in comparison to its predicate device to demonstrate substantial equivalence.
Here's how to frame the information based on the provided text, focusing on the equivalence study presented:
1. A table of acceptance criteria and the reported device performance:
Since this is a 510(k) demonstrating substantial equivalence, the "acceptance criteria" are implied to be that the new device (TiMX) is "generally superior or equivalent" to the predicate device (standard titanium VSP system) in terms of its mechanical performance.
| Performance Metric | Acceptance Criteria (Implied) | Reported Device Performance (TiMX vs. Standard Titanium VSP) |
|---|---|---|
| Torque plus bending performance (Pedicle Screw) | Superior or Equivalent to predicate | Significant improvement in torque plus bending with VSP plates |
| Torque to failure performance (Hexlobe feature) | Superior or Equivalent to predicate | Better torque to failure performance |
| Endurance limit (Pedicle Screw) | Superior or Equivalent to predicate | 30% improvement in endurance limit |
| Static compression bending (System) | Superior or Equivalent to predicate | Generally superior or equivalent |
| Static torsion (System) | Superior or Equivalent to predicate | Generally superior or equivalent |
| Dynamic compression bending (System) | Superior or Equivalent to predicate | Generally superior or equivalent |
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 specified in terms of distinct units or number of tests conducted, but refers to "a full battery of testing" on "both the TiMX and standard titanium VSP systems." This implies testing on physical prototypes of the components and systems.
- Data Provenance: Not specified, but given it's a 510(k) submission in the US, the testing would typically be performed by the manufacturer or a certified lab, likely in the US, for regulatory submission to the FDA. The study is prospective in the sense that the testing was performed on the new device designs to gather data for the submission.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g., radiologist with 10 years of experience):
This is not applicable. The "ground truth" here is objective mechanical engineering measurements (e.g., torque, bending force, fatigue cycles) from physical testing, not expert interpretation of medical data. Therefore, no human experts as described are involved in establishing ground truth for mechanical testing.
4. Adjudication method (e.g., 2+1, 3+1, none) for the test set:
Not applicable, as this is objective mechanical testing. The results would be quantitative measurements, not subjective evaluations requiring adjudication.
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 document describes a physical medical implant (spinal system), not an AI/software device that assists human readers.
6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
Not applicable. This is not an algorithm or software. It is a physical device.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
The "ground truth" for the performance claims is objective mechanical engineering measurements obtained from physical laboratory testing (e.g., static compression bending, static torsion, dynamic compression bending, torque to failure, endurance limit) comparing the new device components and system to the predicate device components and system.
8. The sample size for the training set:
Not applicable. This is a physical device, not a machine learning algorithm that requires a training set. The "training" in manufacturing comes from design iterations and engineering experience.
9. How the ground truth for the training set was established:
Not applicable, as there is no training set in the context of an AI/ML algorithm for this device.
§ 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.