(89 days)
The R3 Constrained Liner Acetabular System is a cemented or uncemented prosthesis intended to replace a hip joint. The Constrained Liner is intended for primary or revision patients at high risk for hip dislocation due to a history of prior dislocation, bone loss, soft tissue laxity, neuromuscular disease, or intra-operative instability and for whom all other options to constrained acetabular components have been considered. The R3 Constrained Liner is intended for single use only.
The R3 Constrained Liners were previously cleared for market via premarket notification K111635. Subject of this premarket notification are minor modifications to the R3 Constrained Liner components, specifically the bipolar shell and inner poly liner.
The R3 Constrained Liners are available with inner diameters of 22 and 28mm and outer diameters from 52mm through 66/70mm. The devices are assembled from components that are made of ASTM F75 CoCr, ASTM F90 CoCr, ASTM F1472 Ti-6AI-4V, and ASTM F648 UHMWPE.
The provided 510(k) summary (K122139) for the Smith & Nephew R3 Constrained Liner describes modifications to an existing device, not an AI/ML-driven device. Therefore, the information requested regarding acceptance criteria, study details, and ground truth establishment, which are typical for AI/ML device evaluations, is not present in this document.
The document focuses on demonstrating substantial equivalence to previously cleared predicate devices through mechanical testing, rather than clinical performance studies.
Here's a breakdown of what is available in the document in relation to your request, and what is not:
1. A table of acceptance criteria and the reported device performance:
- Acceptance Criteria: The document mentions that "Mechanical testing has been conducted to address the attachment loads (push-in, push-out, shuck-out) of the R3 Constrained Liner components as well as to address simulated intraoperative dislocation." The implicit acceptance criterion is that the new device's performance in these mechanical tests demonstrates equivalence to the legally marketed predicate devices.
- Reported Device Performance: The summary states: "A review of the results indicates that the R3 Constrained Liners are equivalent to existing, legally marketed predicate devices with regards to mechanical performance and that there are no new issues related to the safety and effectiveness of the subject devices." Specific numerical performance data from these mechanical tests are not provided in this summary.
2. Sample size used for the test set and the data provenance:
- Not Applicable/Not Provided: Since this is a mechanical testing study on device components, there is no "test set" in the traditional sense of patient data. The "sample size" would refer to the number of physical device components tested, which is not specified in this summary. Data provenance (country of origin, retrospective/prospective) is also not applicable for mechanical testing.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not Applicable: This type of expert assessment is relevant for clinical studies or image interpretation, not mechanical testing of physical implants. The "ground truth" for mechanical tests would be defined by engineering standards and test protocols.
4. Adjudication method for the test set:
- Not Applicable: Adjudication is typically used in clinical studies involving interpretation or outcome assessment.
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:
- No: This is explicitly for AI/ML devices with human-in-the-loop components. This device is a physical hip implant component.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- No: See point 5.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- Mechanical Standards/Engineering Specifications: For mechanical testing, the "ground truth" is established by adherence to recognized engineering standards (e.g., ASTM standards for material properties and test methods) and comparison against the performance of predicate devices as per their design specifications and previous testing.
8. The sample size for the training set:
- Not Applicable/No Training Set: This device does not involve machine learning, so there is no training set.
9. How the ground truth for the training set was established:
- Not Applicable/No Training Set: See point 8.
In summary of the provided text:
The device (R3 Constrained Liner) received 510(k) clearance based on demonstrating substantial equivalence to predicate devices. This was achieved through mechanical testing that assessed attachment loads (push-in, push-out, shuck-out) and simulated intraoperative dislocation. The "acceptance criteria" were met by showing that the modified R3 Constrained Liners performed equivalently to the predicate devices in these mechanical tests, suggesting no new safety or effectiveness concerns. Specific quantitative results of these mechanical tests are not detailed in this summary. No clinical data or AI/ML performance studies were performed or required.
§ 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.”