(29 days)
The M.U.S.T.® Pedicle Screw System is intended for posterior non-cervical pedicle fixation (T1-S2/ilium) or anterolateral fixation (T8-L5). These devices are indicated as an adjunct to fusion for all of the following indications: degenerative disc disease (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; curvatures (i.e., scoliosis, and/or lordosis); tumor; pseudoarthrosis and failed previous fusion in skeletally mature patients.
The M.U.S.T. Extension is intended to be used as part of the M.U.S.T. pedicle screw system (K12115, K132878, K141988) for the stabilization and the fusion of the lumbar and thoracic spine. The M.U.S.T. pedicle screw system includes cannulated or non cannulated poly-axial pedicle screws (K121115, K132878), cannulated or non cannulated mono-axial pedicle screws (K132878), set screws (K121115), straight and pre-bent rods (K12115), and cross connectors (K132878). The M.U.S.T. pedicle screw system also includes the enhanced screws and rods designed for percutaneous surgery (K141988).
This Special 510(k) introduces a new design of the pedicle screw head (Tulip). The new design features two additional tabs in order to perform the rod reduction with the setscrew. The tulip has also changed materials from to CoCrMo to Ti6Al4V ELI.
The size range of the modified Pedicle Screws introduced with this 510(k) is the same as the predicate devices.
The M.U.S.T. Extension consists of the following components, which are all provided in both sterile and unsterile packaging:
Solid Poly-Axial Pedicle Screws: Diameter 4.5, 5, 6, 7mm, Length 20-90mm, Material Ti6Al4V ELI (ISO 5832-3 ASTM F 136)
Cannulated Poly-Axial Pedicle Screws: Diameter 5, 6, 7mm, Length 25-90mm, Material Ti6Al4V ELI (ISO 5832-3 ASTM F 136)
Here's an analysis of the provided FDA 510(k) summary for the M.U.S.T. Pedicle Screw System, focusing on the acceptance criteria and study information:
It's important to note that this document is a 510(k) Summary, which is a concise overview of the information submitted for regulatory clearance. It often highlights the conclusion of testing rather than providing exhaustive detail about the study methodology. Therefore, some specific details you requested may not be explicitly stated.
Acceptance Criteria and Reported Device Performance
The document describes the performance testing in a general way, comparing it to predicate devices rather than providing specific numerical acceptance criteria and results for independent performance.
1. Table of Acceptance Criteria and Reported Device Performance:
| Acceptance Criteria (General) | Reported Device Performance |
|---|---|
| Demonstrated substantial equivalence to predicate devices. | "The device's behavior and performance can be considered equivalent to its predicate." |
| Compliance with ASTM F 1717 standards for mechanical tests. | Tests Performed: Static compression/bending strength, Dynamic compression/bending strength, Static torsion strength. (Implicitly, the results met the standard's requirements or were equivalent to the predicate that met the standard.) |
| Addition of a new pedicle screw head (Tulip) design with two additional tabs for rod reduction. | The component has been introduced as described. Material change from CoCrMo to Ti6Al4V ELI. |
| Use of Ti6Al4V ELI (ISO 5832-3 ASTM F 136) for screws. | Material specified as Ti6Al4V ELI (ISO 5832-3 ASTM F 136) for proposed screws. |
| Size range of modified Pedicle Screws same as predicate devices. | Stated that "The size range of the modified Pedicle Screws introduced with this 510(k) is the same as the predicate devices." |
2. Sample Size for Test Set and Data Provenance:
- Sample Size: Not explicitly stated. For mechanical tests like those performed (ASTM F 1717), the "sample size" refers to the number of devices tested. This information is typically detailed in the full test report, not the 510(k) summary.
- Data Provenance: The device is manufactured by Medacta International, based in Switzerland. The testing was conducted as part of the submission to the FDA in the USA. The data itself is likely laboratory test data, not patient data, given the nature of the device and tests. Therefore, it would be considered prospective experimental data.
3. Number of Experts and Qualifications for Ground Truth (Test Set):
- Not Applicable. This device is a mechanical implant (pedicle screw system), not an AI/imaging diagnostic device. Ground truth, in the context of diagnostic performance, is not relevant for this type of submission. The "ground truth" for a mechanical device is its physical properties and mechanical performance under specified loads, measured against established engineering standards (like ASTM F 1717).
4. Adjudication Method (Test Set):
- Not Applicable. See point 3. Adjudication methods are relevant for subjective assessments of diagnostic performance, not for objective mechanical testing.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
- No. This is not an AI-assisted diagnostic or imaging device. Therefore, an MRMC study is not relevant or applicable.
6. Standalone (Algorithm Only) Performance Study:
- Not Applicable. There is no algorithm or software component described that would have a "standalone" performance. The device is a physical pedicle screw system.
7. Type of Ground Truth Used:
- For mechanical devices subject to ASTM standards, the "ground truth" is defined by the standardized test procedures and measurement techniques to determine parameters like static and dynamic strength and torsion. The device's performance is measured against the specifications and requirements set forth by these engineering standards. In this case, ASTM F 1717.
8. Sample Size for Training Set:
- Not Applicable. There is no "training set" for a mechanical device like this. Training sets are relevant for machine learning algorithms.
9. How Ground Truth for Training Set Was Established:
- Not Applicable. See point 8.
Summary of the Study (as described in the 510(k) summary):
The study was a series of mechanical performance tests conducted to evaluate the M.U.S.T. Pedicle Screw System, specifically focusing on a new design of the pedicle screw head (Tulip) and a change in material.
- Purpose: To demonstrate that the modified device is substantially equivalent to previously cleared predicate devices in terms of mechanical performance and safety.
- Methods:
- A risk analysis was performed to identify new risks associated with the design change.
- Design verification tests were conducted according to written protocols and pre-defined acceptance criteria.
- The protocols and criteria were based on standards (specifically ASTM F 1717), FDA guidance, and comparison to predicate devices.
- The mechanical tests performed were:
- Static compression/bending strength (ASTM F 1717)
- Dynamic compression/bending strength (ASTM F 1717)
- Static torsion strength (ASTM F 1717)
- Conclusion: Based on these tests, the M.U.S.T. Extension (the modified components) was considered substantially equivalent to its predicate devices in behavior and performance.
This type of submission relies on engineering standards and direct comparison to a predicate device's established performance to demonstrate safety and effectiveness for substantial equivalence. It does not involve patient data, clinical trials, or expert diagnostic assessments as would be the case for AI/imaging devices.
§ 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.