(34 days)
The M.U.S.T. Pedicle Screw System is intended for posterior non-cervical pedicle fixation (T1-S2/lium) and nonpedicle fixation, 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, kyphosis, and/or lordosis); tumor; pseudoarthrosis and failed previous fusion in skeletally mature patients.
The M.U.S.T. Extension - Straight Connectors and Additional Screws are intended to be used as part of the M.U.S.T. Pedicle Screws System (K121118, K132878, K141988, K153664) for the stabilization and the fusion of the lumbar and thoracic spine. The M.U.S.T. Pedicle Screws System includes: cannulated or non-cannulated poly-axial pedicle screws (K121115and K132878), cannulated or non-cannulated mono-axial pedicle screws (K132878), set screws (K121115), straight and pre-bent rods (K121115), cross connectors (K132878), enhanced screws and rods designed for percutaneous surgery (K141988), and cannulated or non-cannulated reduction screws (K153664). The M.U.S.T. Additional Pedicle Screws (standard and enhanced pedicle) are made of Ti6Al4V ELI (ISO 5832-3, ASTM F136-13) and CoCrMo (ISO 5832-12, ASTM F1537-11), while the M.U.S.T. Additional Reduction Screws are made of Ti6A14V ELI (ISO 5832-3, ASTM F136-13). The screw shaft is color anodized to simplify the identification of the screw diameter. The pedicle screw has a dual lead thread to simplify the screw insertion and reduce the number of turns. The threads are designed with a cylindrical diameter. The M.U.S.T. Straight Connectors and Additional Screws introduces the following additional components: Pedicle screw, Enhanced Solid Pedicle screw, Enhanced Cannulated Pedicle screw, Reduction Pedicle screw, Reduction Cannulated Pedicle screw, Straight Cross Connector.
The provided document is a 510(k) Premarket Notification for the M.U.S.T. Pedicle Screw System Extension - Straight Connectors and Additional Screws. It focuses on demonstrating substantial equivalence to previously cleared predicate devices through comparisons of technological characteristics and performance testing.
Here's an analysis of the acceptance criteria and study information provided, structured as requested:
1. A table of acceptance criteria and the reported device performance
The document doesn't explicitly list specific numerical acceptance criteria. Instead, it states that the acceptance criteria were "pre-defined" and "based on the standards, FDA guidance, and comparison to the predicate device system." The reported device performance is a general statement that the device "met all acceptance criteria" and "is substantially equivalent to the predicate devices."
| Acceptance Criteria Category | Specific Acceptance Criteria (as implied) | Reported Device Performance |
|---|---|---|
| Mechanical Performance (Dynamic Compression Bending) | Performance equivalent to predicate devices as determined by ASTM F1717-12, considering worst-case device. | Met all acceptance criteria. Performance substantially equivalent to predicate devices. |
| Mechanical Performance (Static Compression Bending) | Performance equivalent to predicate devices as determined by ASTM F1717-12, considering worst-case device. | Met all acceptance criteria. Performance substantially equivalent to predicate devices. |
| Mechanical Performance (Static Torsion) | Performance equivalent to predicate devices as determined by ASTM F1717-12, considering worst-case device. | Met all acceptance criteria. Performance substantially equivalent to predicate devices. |
| Biocompatibility | Material and manufacturing process identical to predicate devices, supporting biological safety. | Deemed unnecessary to conduct additional testing as materials and manufacturing are identical to predicate devices. |
| Technological Characteristics | New diameters and straight connector do not raise new questions of safety or effectiveness compared to predicates. | A comparison evaluation shows no new risks associated with the subject device design. |
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: The document repeatedly mentions "the worst-case device" for each of the mechanical tests (Dynamic Compression Bending, Static Compression Bending, Static Torsion). This implies a very small sample size, potentially a single representative device or a small set of devices configured to represent the most challenging conditions. The exact number is not explicitly stated.
- Data Provenance: The study is a laboratory-based mechanical testing study, not a clinical study involving human or animal data. Therefore, concepts like country of origin, retrospective, or prospective do not apply in the typical sense. It is an engineering verification study.
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 section is not applicable to this type of device and study. The "ground truth" for mechanical testing is established by engineering standards (ASTM F1717-12) and the inherent physical properties and design specifications of the device, rather than expert judgment or clinical outcomes.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
This section is not applicable. Adjudication methods are typically used in clinical studies to resolve discrepancies in expert interpretations of data (e.g., imaging, clinical assessments). For mechanical testing, the "adjudication" is inherent in the adherence to established test standards and the objective measurement of physical properties.
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
A multi-reader multi-case (MRMC) comparative effectiveness study is not applicable to this device. This type of study evaluates the performance of AI-assisted diagnostic or classification systems in a clinical context, often involving human readers interpreting medical images. The M.U.S.T. Pedicle Screw System Extension is a physical orthopedic implant, not an AI diagnostic tool.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
A standalone performance evaluation (in the context of AI algorithms) is not applicable to this device. This device is a physical implant and does not involve any AI algorithms.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
The "ground truth" for the performance data in this document is based on engineering standards and specifications. Specifically, the mechanical tests were performed according to ASTM F1717-12 Standard Test Methods for Spinal Implant Constructs in a Vertebrectomy Model. The acceptance criteria were based on these standards, FDA guidance, and comparison to the predicate device's established performance.
8. The sample size for the training set
This question is not applicable as there is no "training set" in the context of a physical device mechanical performance study. Training sets are relevant for machine learning algorithms.
9. How the ground truth for the training set was established
This question is not applicable for the same reason as point 8.
§ 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.