(199 days)
The EQUATION™ Fixation System is a temporary implant system used for correction and stabilization of the posterior spine for the development of a solid spinal fusion. When used as a pedicle screw fixation system of the non-cervical posterior spine in skeletally mature patients, the EQUATION™ Fixation System is indicated for one or more of the following: (1) degenerative spondylolisthesis with objective evidence of neurologic impairment, (2) fracture, (3) dislocation, (4) scoliosis, (6) spinal tumor, and/or (7) failed previous fusion (pseudarthrosis).
In addition, when used as a pedicle screw fixation system, the EQUATION™ Fixation System is indicated for skeletally mature patients: (a) having severe spondylolisthesis (Grades 3 and 4) of the fifth lumbar-first sacral (L5-S1) vertebral joint; (b) who are receiving fusions using autogenous bone graft only; (c) who are having the device fixed or attached to the lumbar and sacral spine (L3 and below); and (d) who are having the device removed after the development of a solid fusion mass.
The Medtronic Sofamor Danek EQUATION™ Fixation System consists of a variety of shapes and sizes of screws, nuts, and 3.6mm rods and cross connectors. The implant components can be rigidly locked in a variety of configurations, with each construct being tailor-made for the individual case. The implants are made of titanium alloy (Ti-6Al-4V) described by ASTM Standard F136 or ISO 5832-3. Stainless steel and titanium implant components must not be used together in a construct.
The Medtronic Sofamor Danek EQUATION™ Fixation System is a temporary implant system used for correction and stabilization of the posterior spine for the development of a solid spinal fusion. The acceptance criteria and the study that proves the device meets the acceptance criteria are described below.
1. Acceptance Criteria and Reported Device Performance
| Acceptance Criteria | Reported Device Performance |
|---|---|
| The EQUATION™ Fixation System must demonstrate substantial equivalence in functionality and safety to the predicate device, the CD HORIZON® Spinal System, through mechanical testing. | Mechanical testing was performed on the EQUATION™ Fixation System and the results were directly compared to test data previously obtained for the cleared CD HORIZON® Spinal System. The submission states that the test results supported the conclusion of substantial equivalence. |
2. Sample Size and Data Provenance
The document does not explicitly state a "test set" in the context of clinical data or human subjects. The evaluation was primarily based on mechanical testing.
- Sample size for the test set: Not explicitly stated for mechanical testing, but the implication is that sufficient units of the EQUATION™ Fixation System components were tested to make a comparison with the predicate device.
- Data Provenance: The data is from mechanical testing of the device and its components. The country of origin for this testing is not specified, but the submitter is Medtronic Sofamor Danek USA, Inc. The data is prospective in the sense that the testing was conducted specifically for this submission.
3. Number of Experts and Qualifications for Ground Truth
Not applicable. The "ground truth" for this device's performance is established through mechanical engineering principles and testing standards, not through expert clinical consensus on images or patient data. No human experts were used to establish ground truth in the way it is typically understood for diagnostic AI.
4. Adjudication Method for the Test Set
Not applicable. As the evaluation was based on mechanical testing, there was no need for an adjudication method as would be used with human readers or clinical data. The results of mechanical tests are usually objective measurements.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
Not applicable. This device is a surgical implant, not a diagnostic or AI-assisted system requiring a MRMC study.
6. Standalone (Algorithm Only) Performance Study
Not applicable. This is a physical medical device (spinal fixation system), not a software algorithm.
7. Type of Ground Truth Used
The ground truth used was objective mechanical test results that demonstrate the physical performance, strength, and durability of the device components, comparing them against the established performance of the legally marketed predicate device (CD HORIZON® Spinal System). The safety and effectiveness are inferred from demonstrating equivalent mechanical properties to a device already deemed safe and effective.
8. Sample Size for the Training Set
Not applicable. There is no "training set" in the context of an AI/algorithm. For a physical device, the development and manufacturing process involves iterative design and testing, but these are not referred to as "training sets."
9. How the Ground Truth for the Training Set was Established
Not applicable as there is no training set. Design specifications and engineering requirements guide the development of such a device, and compliance with these, along with comparison to predicate devices, forms the basis of its "ground truth" for regulatory approval.
§ 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.