(209 days)
The Stryker Hoffmann LRF (Limb Reconstruction Frame) System is indicated in pediatric patients and adults for the treatment and fixation of:
- Open and Closed Fractures
- Post-traumatic joint contracture which has resulted in loss of range of motion
- Fractures and disease which generally may result in joint contractures or motion and fractures requiring distraction
- Pseudoarthrosis or non-union of long bones
- Limb lengthening by epiphyseal or metaphyseal distraction
- Correction of bony or soft tissue deformity
- Correction of segmental bony or soft tissue defects
- Joint arthrodesis
- Management of comminuted intra-articular fractures of the distal radius
The Stryker Hoffmann LRF System is indicated in adults for:
- Osteotomy
- Revision procedure where other treatments or devices have been unsuccessful
- Bone reconstruction procedures
- Fusions and replantations of the foot
- Charcot foot reconstruction
- Lisfranc dislocations
Originally cleared in K113327, the Hoffmann LRF System is an external fixation device that consists of carbon and aluminum full/open rings and ring segments, aluminum foot rings, threaded rods and threaded rod connecting nuts, telescopic struts, static struts and connection bolts, posts and connecting nuts, wires and wire bolt offset adapters, pin bolts and pin adapters, and washers.
Modifications to the previously cleared telescopic strut and wire bolt components, as part of the currently marketed Hoffmann LRF (Limb Reconstruction Frame) System in K113327, were cleared in K130334.
Additional components (carbon foot ring, foot arch, hinge coupling) were cleared in K130907 as a line extension to the currently marketed Hoffmann LRF (Limb Reconstruction Frame) System in K113327.
This Traditional 510(k) submission is being supplied to the U.S. FDA to provide authorization to market the inclusion of additional components to the previously cleared Hoffmann LRF (Limb Reconstruction Frame) System, in K130907. The additional components of this submission will consist of the following: constrained hinge strut, universal hinge strut, motor struts, spherical washer, hinge bolt, self-locking nut, half hinge, universal joint, adjustment instrument, slotted plate and buckle.
This external fixation system may also be used with the components of other Stryker Trauma AG external fixation systems such as the Monticelli Spinelli External Fixation System, the Hoffmann II, Hoffman II MRI and Hoffmann 3 External Fixation System, and the Apex Fixation Pins.
The provided FDA 510(k) summary for the Hoffmann LRF (Limb Reconstruction Frame) System describes a medical device, not an AI/ML-driven diagnostic or prognostic tool. Therefore, the information requested about acceptance criteria for AI models, sample sizes for training/test sets, expert ground truth, MRMC studies, standalone performance, and data provenance is not applicable in this context.
This submission is for additional components to an existing external fixation device, and the evaluation relies on non-clinical laboratory testing to demonstrate substantial equivalence to predicate devices, rather than clinical performance data or AI model validation.
Here's the relevant information from the document as it pertains to the device's performance demonstration:
1. A table of acceptance criteria and the reported device performance
| Acceptance Criteria (Implied by standard) | Reported Device Performance (Summary) |
|---|---|
| Compliance with ASTM F1541-02 | Testing demonstrated substantial equivalence to the predicate device components. |
| Sufficient mechanical strength/durability for intended use (implied by specific tests) | Passed Static Cantilever Bending Test, Dynamic Cantilever Bending Test, Dynamic Frame Testing. |
Note: The document states "Testing demonstrated that the Hoffmann LRF (Limb Reconstruction Frame) System added components are substantially equivalent to the predicate device components." The specific quantitative acceptance values (e.g., maximum deflection, fatigue life cycles) from ASTM F1541-02 and the precise performance metrics achieved are not detailed in this summary. The "acceptance criteria" here are implied by the standard itself and the need to show equivalence.
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 does not specify the number of components or test units used for each non-clinical test (Static Cantilever Bending, Dynamic Cantilever Bending, Dynamic Frame Testing).
- Data Provenance: This relates to non-clinical laboratory testing of mechanical properties, not patient data. It was performed by Stryker Trauma AG, headquartered in Switzerland, though the specific lab location is not stated. These are "prospective" engineering tests designed to evaluate the physical properties of the device components.
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)
Not applicable. Ground truth, in the context of AI models, refers to expert-labeled data. For a physical medical device, "ground truth" for non-clinical testing is typically defined by engineering specifications, material properties, and established test standards (e.g., ASTM F1541-02). The "experts" would be the engineers and technicians conducting and analyzing the mechanical tests. Their qualifications are not specified but would be standard for mechanical engineering and materials testing.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
Not applicable. Adjudication methods are used to resolve discrepancies in expert labeling for AI ground truth. For mechanical testing, if there were issues, they would typically involve repeated tests, calibration checks, or review by senior engineers. The document does not mention an adjudication method.
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
Not applicable. This device is an external fixation system, not an AI-assisted diagnostic or prognostic tool. No human readers, cases, or AI assistance are involved in its performance evaluation as described here.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Not applicable. This is not an algorithm or AI model. The "standalone" testing refers to the non-clinical mechanical tests where the device components were tested without human intervention impacting the mechanical properties being measured.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
The "ground truth" for this device's performance in non-clinical testing is based on:
- Engineering Specifications: The design parameters and material specifications of the device components.
- Standardized Test Methods: Adherence to established industry standards like ASTM F1541-02, which provides defined procedures and expected performance envelopes for external skeletal fixation devices.
- Predicate Device Performance: The mechanical performance of the legally marketed predicate devices, against which the new components are shown to be "substantially equivalent."
8. The sample size for the training set
Not applicable. There is no training set as this is not an AI/ML device.
9. How the ground truth for the training set was established
Not applicable. There is no training set for an AI/ML device.
§ 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.