(192 days)
The tangoRS™ is intended to provide immobilization and stabilization of spinal segments as an adjunct to fusion of the thoracic, lumbar and sacral spine (T1-S2). When used as a posterior spine thoracic/lumbar system, the tangoRS is intended for the following indications: degenerative disc disease (as defined by back pain of discogenic with degeneration of the disc confirmed by patient history and radiographic studies), spinal stenosis, spondylolisthesis, spinal deformities (i.e., degenerative scoliosis, kyphosis, and/or lordosis), fracture, spinal tumor, pseudarthrosis and failed previous fusion.
The tangoRS™ consists of rods, polyaxial pedicle screws and crosslinks with locking set screws. The components are available in various sizes to accommodate differing patient anatomy. Rods are available in one diameter and a variety of lengths. Polyaxial screws are available in a variety of diameter-length combinations. Crosslinks are offered in four lengths. The purpose of this submission is to add components (a screw size and crosslink options) and two indications for use.
The provided 510(k) summary for the tangoRS™ multifunctional posterior system describes its performance through mechanical testing. Here's an analysis of the acceptance criteria and the study that proves the device meets them:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criterion (Implicit) | Reported Device Performance |
|---|---|
| Biocompatibility (Material safety) | Components manufactured from titanium alloy (Ti-6Al-4V ELI) as described by ASTM F136. |
| Mechanical Strength and Durability (Static Compression Bending) | tangoRS™ performs as well as or better than predicate devices according to ASTM F1717 testing. |
| Mechanical Strength and Durability (Dynamic Compression Bending) | tangoRS™ performs as well as or better than predicate devices according to ASTM F1717 testing. |
| Mechanical Strength and Durability (Static Torsion) | tangoRS™ performs as well as or better than predicate devices according to ASTM F1717 testing. |
| Substantial Equivalence to Predicate Devices (Technological Characteristics & Intended Use) | Same intended use, basic design (rod-based, screw anchors), material (titanium alloy), and comparable sizes to predicate devices. |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: The document does not specify a "sample size" in terms of individual patients or clinical cases for a test set. The performance evaluation is based on mechanical testing of "worst case tangoRS™ constructs." The exact number of constructs tested is not provided, but it would typically involve multiple samples for each test condition to ensure reproducibility.
- Data Provenance: The data is generated from in-vitro (benchtop) mechanical testing, not from patient-derived data. Therefore, there's no country of origin for clinical data, and it is not retrospective or prospective in the clinical sense.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
This information is not applicable to this type of submission. Mechanical testing does not involve human experts establishing "ground truth" on patient data. The "ground truth" for mechanical testing is established by the specified ASTM F1717 standard and the performance of predicate devices.
4. Adjudication Method for the Test Set
This is not applicable as the study is mechanical testing, not a clinical study involving human judgment that would require adjudication.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No, an MRMC comparative effectiveness study was not done. This submission relies on mechanical bench testing, not clinical studies involving human readers.
6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study
This is not applicable. The device is a physical medical implant (pedicle screw system), not an algorithm or software. Therefore, there's no concept of "standalone performance" in the context of an algorithm. The performance described is inherent to the device's physical and mechanical properties.
7. Type of Ground Truth Used
The "ground truth" used for this type of device and submission is based on:
- ASTM F1717 standards: These provide the accepted methodology and criteria for testing spinal implant constructs.
- Performance of predicate devices: The tangoRS™ system is compared against the mechanical performance of previously cleared predicate devices (flamenco™ {K102853}, CD HORIZON® {K031655/K041460}, Expedium {K041119/K062196}, tangoRS™ {K052385}). The implicit "ground truth" is that if the new device performs "as well as or better than" these established devices under standardized testing, it is considered safe and effective.
8. Sample Size for the Training Set
This is not applicable. There is no "training set" in the context of mechanical testing for a physical implant. The design of the tangoRS™ system is based on established engineering principles and knowledge gained from predicate devices, but there isn't a "training set" of data in the machine learning sense.
9. How the Ground Truth for the Training Set Was Established
This is not applicable as there is no "training set" for this type of device and study. The physical design and materials are chosen based on known biomechanical requirements and historical performance of similar 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.