(17 days)
The Freedom™ Constrained Liners are indicated for use as a component of a total hip prosthesis in primary and revision patients at high risk of dislocation due to a history of prior dislocation, bone loss, joint or soft tissue laxity, neuromuscular disease, or intra-operative instability, and for whom all other options to constrained acetabular components have been considered.
The Freedom™ Constrained Liners are intended to replace a hip joint. The devices are intended for general use in skeletally mature individuals undergoing primary and/or secondary revision surgery at high risk of hip dislocation due to a history of prior dislocation, joint or bone loss, soft laxity, neuromuscular disease, or intra-operative instability and for whom all other options to constrained acetabular components have been considered.
The Freedom™ Constrained Acetabular Liners are polyethylene liners that will come pre-assembled with a retaining ring already in place. The liners will be available in five different styles. All the liners allow for the same range of motion. The locking mechanism and profile of that mechanism remain the same throughout the series.
The provided text describes a 510(k) premarket notification for a medical device, the Freedom™ Constrained Liners. This document focuses on demonstrating substantial equivalence to a predicate device rather than fulfilling specific acceptance criteria through a study with the characteristics described in your request (e.g., sample sizes for test and training sets, expert qualifications, adjudication methods for AI performance).
Here's a breakdown based on the information provided, highlighting what's applicable and what's not:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Mechanical Similarity to Predicate Device: The Freedom™ Constrained Liners must demonstrate similar mechanical properties and design to the legally marketed predicate device, Ringloc® II Constrained Liners (K021728). | Met. "Mechanical testing, published medical literature, and engineering justifications determined that the Freedom™ Constrained Liner presented no new unacceptable risks and is, therefore, substantially equivalent to the predicate device." |
| Material Composition: Materials used in the Freedom™ liners must be similar or identical to the predicate device. | Met. "The Freedom™ Constrained Liners-the materials, design, sizing, and indications are similar or identical to the predicate devices." |
| Design, Sizing, and Indications: Design, sizing, and indications for use must be similar or identical to the predicate device. | Met. "The Freedom™ Constrained Liners-the materials, design, sizing, and indications are similar or identical to the predicate devices." |
| Safety: Must present no new unacceptable risks. | Met. "Mechanical testing, published medical literature, and engineering justifications determined that the Freedom™ Constrained Liner presented no new unacceptable risks..." |
| No New Unacceptable Risks: The device should not introduce any new unacceptable risks compared to the predicate. | Met. "...presented no new unacceptable risks and is, therefore, substantially equivalent to the predicate device." |
2. Sample size used for the test set and the data provenance
- Not Applicable. This submission is for a mechanical orthopedic device, not an AI/software device that would typically involve a "test set" in the context of an algorithm's performance. The "testing" referred to is mechanical testing of the device itself.
- Data Provenance: The document mentions "published medical literature" as part of the justification, but no specific data provenance related to AI model testing.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Not Applicable. Ground truth in the context of expert consensus is relevant for evaluating AI performance on diagnostic tasks, not for the mechanical safety/equivalence of an orthopedic implant.
4. Adjudication method (e.g., 2+1, 3+1, none) for the test set
- Not Applicable. See point 3.
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 is a medical device (hip prosthesis component), not an AI-powered diagnostic or assistive tool. Therefore, MRMC studies are not relevant to this submission.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Not Applicable. This is a physical medical device, not an algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
- The "ground truth" or basis for acceptance in this context is the performance and safety profile of the predicate device (Ringloc® II Constrained Liners), established through previous regulatory clearance (K021728). The new device's ground truth is its demonstrated mechanical equivalence and lack of new unacceptable risks compared to this established predicate. The documentation relies on:
- Mechanical testing: To compare physical properties and performance.
- Published medical literature: To support the understanding of the device's components and design.
- Engineering justifications: To explain how the device's design is similar or identical to the predicate.
8. The sample size for the training set
- Not Applicable. This is not an AI/machine learning device.
9. How the ground truth for the training set was established
- Not Applicable. See point 8.
In summary:
This 510(k) submission for the Freedom™ Constrained Liners is based on establishing substantial equivalence to a predicate device (Ringloc® II Constrained Liners) through non-clinical testing (mechanical testing, literature review, engineering justifications). It explicitly states "Clinical Testing: None provided as a basis for substantial equivalence." The acceptance criteria revolve around the device's physical properties, design, materials, and indications being similar or identical to the predicate, and presenting no new unacceptable risks. The concept of "acceptance criteria" as applied to AI performance studies does not directly apply to this type of medical device submission.
§ 888.3310 Hip joint metal/polymer constrained cemented or uncemented prosthesis.
(a)
Identification. A hip joint metal/polymer constrained cemented or uncemented prosthesis is a device intended to be implanted to replace a hip joint. The device prevents dislocation in more than one anatomic plane and has components that are linked together. This generic type of device includes prostheses that have a femoral component made of alloys, such as cobalt-chromium-molybdenum, and an acetabular component made of ultra-high-molecular-weight polyethylene with or without a metal shell, made of alloys, such as cobalt-chromium-molybdenum and titanium alloys. This generic type of device is intended for use with or without bone cement (§ 888.3027).(b)
Classification. Class II (special controls). The special control for this device is the FDA guidance document entitled “Class II Special Controls Guidance: Hip Joint Metal/Polymer Constrained Cemented or Uncemented Prosthesis.”