(75 days)
The Stryker VariAx 2 System is intended for internal bone fixation in adult patients.
The Stryker VariAx 2 System screws, when used in conjunction with VariAx Plating Systems; or used independently in a lag screw technique, are indicated for:
- Internal fracture fixation;
- Osteotomies:
- Revision procedures such as non-unions or mal-unions;
In addition, the following indications are specific to the devices listed below:
- T8 2.4mm Screws & T8 2.0mm Locking Peg: For use in small bones, primarily including the Distal Radius, in the treatment of:
- Compression fractures:
- Intra-articular and extra-articular fractures;
- Displaced fractures;
- Reconstruction procedures;
- T8 2.7mm Screws: For use in small bones, including the Distal Radius as well as the fore, midand hind Foot and Ankle, in the treatment of:
- Intra-articular and extra-articular fractures of the Distal Radius,
- Displaced and compression fractures of the Distal Radius;
- Replantation, joint fusions or arthrodesis and corrective osteotomies in the Foot & Ankle;
- Reconstruction procedures in the Foot & Ankle and Distal Radius:
- T10 3.5mm and T10 2.7mm Screws: For use in the Radius, Ulna, Clavicle, Humerus, Foot and Ankle, Distal Tibia and Fibula, in the treatment of:
- Intra-articular and extra-articular fractures of the Distal Humerus and Proximal Ulna:
- Single, segmental and comminuted fractures;
- Replantation, joint fusions or arthrodesis and corrective osteotomies in the Foot & Ankle:
- Normal bone density or osteopenic bone.
The VariAx 2 System is an internal fixation device consisting of screws and instrumentation that will be used in conjunction with previously cleared VariAx Plating Systems to treat a number of different types of fractures in the radius, ulna, humerus, clavicle, foot, and fibula. These screws can be used in conjunction with said plating systems, or in the case of non-locking screws, may also be used independently using a lag screw technique. The subject components will be available sterile and non-sterile.
The VariAx 2 System is a medical device designed for internal bone fixation. Its acceptance was determined through non-clinical laboratory testing, demonstrating substantial equivalence to previously cleared predicate devices.
1. Acceptance Criteria and Reported Device Performance:
| Test Performed | Acceptance Criteria | Reported Device Performance |
|---|---|---|
| Screw Pull-Out Testing | Performance comparable to predicate devices | Substantially equivalent to predicate devices |
| Screw Shear-Off Testing | Performance comparable to predicate devices | Substantially equivalent to predicate devices |
| Screw Insertion Torque Testing | Performance comparable to predicate devices | Substantially equivalent to predicate devices |
| Static Cantilever Bending of Locking Mechanism | Performance comparable to predicate devices | Substantially equivalent to predicate devices |
| Dynamic Fatigue Plate-Screw Construct Testing | Performance comparable to predicate devices | Substantially equivalent to predicate devices |
Note: The document does not provide specific numerical values for the acceptance criteria or reported performance. The "acceptance criteria" and "reported device performance" are inferred from the statement "Testing demonstrated that the VariAx 2 System is substantially equivalent to the predicate devices currently cleared for marketing."
2. Sample Size and Data Provenance for Test Set:
- Sample Size: The document does not specify the sample size used for each non-clinical test.
- Data Provenance: Not applicable as the testing was non-clinical laboratory testing. The country of origin for the sponsor, Stryker Trauma AG, is Switzerland.
3. Number and Qualifications of Experts for Ground Truth:
Not applicable. The regulatory pathway for this device (510(k)) focuses on substantial equivalence through non-clinical testing for fracture fixation systems, not on human expert assessment for image interpretation or diagnosis. Therefore, no experts were used to establish ground truth in the context of image interpretation.
4. Adjudication Method for Test Set:
Not applicable. This was a non-clinical device testing study, not a clinical study involving human judgment or interpretation requiring adjudication.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
No, a multi-reader multi-case (MRMC) comparative effectiveness study was not performed. The submission explicitly states, "Clinical testing was not required for this submission."
6. Standalone Performance Study:
Yes, in a way. The non-clinical laboratory tests assess the performance of the device components (screws and plate-screw constructs) in isolation, under controlled laboratory conditions, to determine their mechanical properties and functional equivalence to predicate devices. This represents an "algorithm only without human-in-the-loop performance" in the context of a physical device's mechanical integrity.
7. Type of Ground Truth Used:
The ground truth used for proving the device meets acceptance criteria was based on engineering and mechanical performance benchmarks established by predicate devices and recognized industry standards for bone fixation appliances. These benchmarks are inherently quantitative and objective, derived from physical testing.
8. Sample Size for the Training Set:
Not applicable. This device is a physical bone fixation system, not an AI/ML algorithm. Therefore, there is no "training set" in the context of machine learning.
9. How the Ground Truth for the Training Set Was Established:
Not applicable, as there is no training set for this type of medical device submission.
§ 888.3030 Single/multiple component metallic bone fixation appliances and accessories.
(a)
Identification. Single/multiple component metallic bone fixation appliances and accessories are devices intended to be implanted consisting of one or more metallic components and their metallic fasteners. The devices contain a plate, a nail/plate combination, or a blade/plate combination that are made of alloys, such as cobalt-chromium-molybdenum, stainless steel, and titanium, that are intended to be held in position with fasteners, such as screws and nails, or bolts, nuts, and washers. These devices are used for fixation of fractures of the proximal or distal end of long bones, such as intracapsular, intertrochanteric, intercervical, supracondylar, or condylar fractures of the femur; for fusion of a joint; or for surgical procedures that involve cutting a bone. The devices may be implanted or attached through the skin so that a pulling force (traction) may be applied to the skeletal system.(b)
Classification. Class II.