(246 days)
The WASTON General Spinal System is intended for posterior pedicle screw fixation of the non-cervical posterior spine in skeletally mature patients. It provides stabilization of spinal segments as an adjunct to fusion in the treatment of the following acute and chronic instabilities deformities: (1) trauma (i.e. fracture or dislocation), (2) curvatures (scoliosis, kyphosis, and/or lordosis), (3) spinal tumor, (4) failed previous fusion, (5) spinal stenosis. It is not intended for pedicle screw fixation above T8.
The WASTON General Spinal System consists of Fixed-Angle Screws, Fixed-Angle Reduction Screws, Rods, Crosslink and Set Screws. The proposed general spinal system is made of Titanium Alloy (Ti6Al4VELI), which meets ASTM F136-02a, Standard Specification for Wrought Titanium-6 Aluminum-4 Vanadium ELI (Extra Low Interstitial) Alloy for Surgical Implant Applications, which are widely used for surgical implants with well-known biocompatibility. The proposed devices are provided non-sterile. It is required to be sterilized via autoclave method to reach a SAL of 10th by the hospital prior to surgery. The recommended sterilization method was validated per ISO 17665-1: 2006 Sterilization of health care products -- Moist heat -- Part 1: Requirements for the development, validation, and routine control of a sterilization process for medical devices.
The document provided is a 510(k) premarket notification for the WASTON General Spinal System, identifying it as a Class II medical device. The submission primarily focuses on demonstrating substantial equivalence to a predicate device (Trauson General Spinal System, K082617) through non-clinical testing.
Here's an analysis of the acceptance criteria and study information based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Standard) | Reported Device Performance |
|---|---|
| ASTM F1717-14: Standard Test Methods for Spinal Implant Constructs in a Vertebrectomy Model, including: | The non-clinical tests demonstrated that the proposed device met "all design specifications" and complied with the ASTM F1717-14 standard. Specific quantitative results (e.g., maximum load, displacement, cycles to failure) are not provided in this summary. The summary states that the tests included: |
| - Static compression bending test | (Implied compliance, no specific numeric results provided) |
| - Dynamic compression bending test | (Implied compliance, no specific numeric results provided) |
| - Static torsion test | (Implied compliance, no specific numeric results provided) |
| Sterilization validation per ISO 17665-1: 2006 | The recommended sterilization method (autoclave) was validated per ISO 17665-1: 2006 to achieve a Sterility Assurance Level (SAL) of 10^-6, ensuring the devices are sterile prior to use. |
| Biocompatibility (Material) | The device is made of Titanium Alloy (Ti6Al4VELI), which meets ASTM F136-02a, and is noted for its "well-known biocompatibility" for surgical implant applications. |
| Substantial Equivalence to predicate (K082617) through comparison of technological characteristics and intended use. | Based on the comparison of product code, regulation number, intended use (with minor differences noted but deemed equivalent for SE), configurations (with minor differences), material, sterilization, and single-use status, the proposed device was determined to be "Substantially Equivalent (SE)" to the predicate. |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size for Test Set: The document does not specify the exact sample size for the mechanical tests conducted per ASTM F1717-14. It only states that "Non clinical tests were conducted." Typically, these tests involve multiple samples for each component or construct configuration, but the precise numbers are not disclosed in this summary.
- Data Provenance: The device manufacturer is Changzhou Waston Medical Appliance Company, Limited, located in China. Therefore, the non-clinical test data was likely generated in China, associated with the manufacturer or a contracted testing facility. The data is retrospective in the sense that the tests were completed before the 510(k) submission.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
- This information is not applicable to this submission. The "test set" in this context refers to non-clinical, mechanical performance testing of a spinal implant system. The "ground truth" is established by adherence to a recognized standard (ASTM F1717-14) and the physical properties of the materials and device design, rather than expert interpretation of data.
4. Adjudication Method for the Test Set
- This information is not applicable to this submission. Adjudication methods like 2+1 or 3+1 are typically used in clinical studies for interpreting human-read data or clinical endpoints. For mechanical testing against a standard, the results are objectively measured and compared to the standard's pass/fail criteria, often requiring a pass for all tested samples.
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
- No, an MRMC comparative effectiveness study was not done. The document explicitly states: "No clinical study is included in this submission." This type of study is relevant for AI-powered diagnostic or interpretive devices, which is not the case for a spinal implant system.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
- No, a standalone algorithm performance study was not done. This device is a physical spinal implant system, not an algorithm or AI-based diagnostic tool. Therefore, a standalone algorithm performance study would not be relevant.
7. The Type of Ground Truth Used
- For the non-clinical testing, the "ground truth" is typically defined by established engineering standards and material specifications. The device's performance is compared against the requirements and methodologies outlined in:
- ASTM F1717-14 for mechanical performance (static compression bending, dynamic compression bending, static torsion).
- ASTM F136-02a for material composition and properties.
- ISO 17665-1: 2006 for sterilization validation.
8. The Sample Size for the Training Set
- This information is not applicable to this submission. "Training set" refers to data used to train machine learning models. As this device is a physical spinal implant system and does not involve AI or algorithms, there is no training set in this context.
9. How the Ground Truth for the Training Set was Established
- This information is not applicable as there is no training set for this type of 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.