(44 days)
Indications for the Heidelberg Fixator include: fracture fixation (open and closed); pseudoarthrosis or nonunion of long bones; limb lengthening, correction of bony or soft tissue deformity; correction of segmental bony or soft tissue defects; and joint arthrodesis.
The Heidelberg External Fixator is a modular unilateral, extensible device used for the indications listed previously. Components are made of aluminum, stainless steel, cobalt alloy, brass, and nylon which are similar to materials used in other unilateral fixators.
The provided text describes the "Heidelberg External Fixator," a medical device. This document is a summary of safety and effectiveness and substantial equivalence information submitted to a regulatory body (likely the FDA, given the "K" numbers for predicate devices, which are common in 510(k) submissions).
Crucially, this document describes a physical medical device (an external fixator), not a diagnostic algorithm or AI system. Therefore, the concepts of acceptance criteria and studies related to "device performance" in the context of an algorithm's accuracy, sensitivity, specificity, MRMC studies, standalone performance, training sets, ground truth establishment, or expert consensus simply do not apply to this type of device and submission.
The "study that proves the device meets the acceptance criteria" in this context is based on substantial equivalence to predicate devices already on the market. This means demonstrating that the new device has the same intended use, similar technological characteristics, and raises no new questions of safety or effectiveness compared to legally marketed devices.
Here's how to address the request based on the provided text:
Acceptance Criteria and Study for Heidelberg External Fixator
The Heidelberg External Fixator is a physical medical device. Its acceptance criteria and the study proving it meets these criteria are based on regulatory substantial equivalence, not statistical performance metrics typically associated with diagnostic algorithms or AI.
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria Category | Specific Criteria (Implied by Substantial Equivalence) | Reported Device Performance (as stated in the document) |
|---|---|---|
| Intended Use | Same as predicate devices | Indications are consistent with predicate devices (fracture fixation, pseudoarthrosis, limb lengthening, deformity correction, joint arthrodesis). |
| Material Composition | Similar materials to predicate devices | Components made of aluminum, stainless steel, cobalt alloy, brass, and nylon. Similar to materials used in other unilateral fixators. |
| Design Characteristics | Similar design to predicate devices | Modular unilateral, extensible device. |
| Safety & Effectiveness | No new questions of safety or effectiveness | "The safety and effectiveness of external fixators is based on the long history of use of these devices in the market place." (Implies no red flags raised by this specific design). |
2. Sample Size Used for the Test Set and Data Provenance
Not applicable. This is a substantial equivalence submission for a physical device, not an algorithm being tested on a data set. There is no "test set" in the sense of a dataset for an AI model. The "proof" is based on comparison to already marketed, established devices.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of those Experts
Not applicable. Ground truth establishment with experts is relevant for diagnostic algorithms where a definitive labeling of data is required. For a physical fixator, "ground truth" relates to clinical outcomes and safety over time, which is established by the general use history of similar devices.
4. Adjudication Method for the Test Set
Not applicable. There is no "test set" or adjudication process for labeling data in this context.
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. MRMC studies are for evaluating diagnostic accuracy with human readers, often involving AI assistance. This device is a physical fixator, not a diagnostic tool or AI assistance system.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
Not applicable. This is not an algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
The "ground truth" for the safety and effectiveness of this type of device is implicitly the long history of clinical use and positive outcomes (or lack of widespread severe adverse events) of similar predicate devices in the marketplace.
8. The sample size for the training set
Not applicable. There is no "training set" for a physical medical device. This term is specific to machine learning algorithms.
9. How the ground truth for the training set was established
Not applicable. As there is no training set, there's no ground truth establishment for it.
Summary Explanation:
The "study" demonstrating that the Heidelberg External Fixator meets its "acceptance criteria" is the demonstration of substantial equivalence to already legally marketed predicate devices (Hex-Fix Field Fixator, Orthofix External Fixator, Ilizarov External Fixator System).
The acceptance criteria are implicitly met if:
- The device has the same intended use.
- It has similar technological characteristics (e.g., modular, extensible, made of similar materials).
- It raises no new questions of safety or effectiveness compared to the predicate devices.
The "proof" is in the comparison provided: "All of the devices listed above have similar indications for use, similar materials composition, and similar design. The safety and effectiveness of external fixators is based on the long history of use of these devices in the market place." This statement is the regulatory body's basis for finding the device "substantially equivalent" and thus accepting it.
§ 888.3040 Smooth or threaded metallic bone fixation fastener.
(a)
Identification. A smooth or threaded metallic bone fixation fastener is a device intended to be implanted that consists of a stiff wire segment or rod made of alloys, such as cobalt-chromium-molybdenum and stainless steel, and that may be smooth on the outside, fully or partially threaded, straight or U-shaped; and may be either blunt pointed, sharp pointed, or have a formed, slotted head on the end. It may be used for fixation of bone fractures, for bone reconstructions, as a guide pin for insertion of other implants, or it may be implanted through the skin so that a pulling force (traction) may be applied to the skeletal system.(b)
Classification. Class II.