(296 days)
The intended use of this additional style of System 12® acetabular inserts is identical to that of previously released System 12® inserts: they are intended to be used with Osteolock/Vitalock acetabular shells in primary or revision total hip arthroplasty.
The purpose of this submission is to describe an additional style of System 12® acetabular inserts which are stabilized/sterilized using a process called Duration® II Stabilization. The purpose of the Duration® Il process is to crosslink all of the free radicals found in the UHMWPE rod stock by exposure to gamma radiation followed by a stabilization process in a heated oven. During this radiation/stabilization period, the UHMWPE is exposed to a very low oxygen concentration. The stabilized rod stock is then machined to its final configuration. The acetabular insert is packaged in air, and terminally sterilized by the gas plasma sterilization process. The System 120 Acetabular Inserts produced by this method conform to the requirements for Ultra High Molecular Weight Polyethylene specified in ASTM Specification F-648, and the FDA guidance document on UHMWPE used in Bearing Surfaces for Orthopedic Devices.
These System 12® inserts are identical in design to previously cleared System 12® inserts: they are available in a range of outer diameter sizes to mate with the respective acetabular shell, and 22.0, 22.2, 26, 28, and 32mm inner diameters to mate with Howmedica femoral heads. These inserts are available in a neutral, 10°, and 15° hooded design. The locking mechanism of this style of acetabular insert is identical to previously released System 12® acetabular inserts.
The provided text summarizes a 510(k) submission for the Duration® II System 12® Acetabular Inserts. This device is an additional style of acetabular insert intended for use in total hip arthroplasty, and the submission focuses on its manufacturing process (Duration® II Stabilization and gas plasma sterilization) and its substantial equivalence to previously cleared devices.
Here's an analysis of the acceptance criteria and supporting studies based on the provided text, structured as requested:
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria are presented as "marketing claims" in the document, which are essentially performance standards the device aims to meet.
| Acceptance Criteria (Marketing Claims) | Reported Device Performance |
|---|---|
| 1. Duration® II products meet all ASTM F 648 specified standards. | The document states: "The System 12® Acetabular Inserts produced by this method conform to the requirements for Ultra High Molecular Weight Polyethylene specified in ASTM Specification F-648, and the FDA guidance document on UHMWPE used in Bearing Surfaces for Orthopedic Devices." (Implied: They meet the standard). |
| 2. Duration® II products have no detectable oxidation as measured by FTIR up to 30 days of accelerated aging at 80° C in air. | Although not directly stated as a "performance" figure, the claim itself implies that testing confirmed "no detectable oxidation" under the specified conditions. |
| 3. Duration® II products have a higher gel content (cross-linking) than air irradiated UHMWPE measured in accordance with modified ASTM D2765-90 standard. | The claim explicitly states: "higher gel content (cross-linking)." This implies a comparative test was performed, and the Duration® II material showed superiority in this aspect. |
| 4. Duration® II has a lower tensile modulus than air irradiated UHMWPE. This lower stiffness has demonstrated an increase in contact area and a decrease in contact stress. | The claim explicitly states: "lower tensile modulus than air irradiated UHMWPE." This implies a comparative test was performed, and the Duration® II material showed superiority in this aspect, leading to increased contact area and decreased contact stress. |
| 5. No free radicals are detected in the Duration® II material when analyzed by the ESR technique of the final product. | The claim explicitly states: "No free radicals are detected... by the ESR technique." This implies that the ESR analysis confirmed the absence of free radicals. |
| 6. Duration® II has a lower wear rate, as measured by hip wear simulator than air irradiated UHMWPE. | Reported: "an average total wear of 168.60 ± 50.71 mm³ instead of 310 ± 40.8 mm³." This clearly demonstrates a significantly lower wear rate for Duration® II. |
2. Sample Size Used for the Test Set and Data Provenance
The document does not explicitly state the sample sizes for the individual tests (e.g., FTIR, tensile modulus, ESR). It refers generally to "Testing was performed in accordance with the draft FDA guidance on UHMWPE."
- Data Provenance: The studies appear to be prospective laboratory/in vitro testing conducted by Howmedica. The country of origin of the data is not specified beyond being generated by the applicant (Howmedica, located in New Jersey, USA). There is no mention of human clinical data or retrospective patient data.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
This section is not applicable to this submission. The "ground truth" for the tests described is based on established engineering and materials science standards (ASTM, FTIR, ESR, hip wear simulation) rather than expert clinical consensus or interpretation of patient data. The results are objective measurements.
4. Adjudication Method for the Test Set
This section is not applicable. As the tests are objective material property and wear measurements, there is no need for an adjudication method by human observers.
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
This section is not applicable. The device is a medical implant (acetabular insert), not an AI-powered diagnostic or assistive technology. Therefore, an MRMC study related to AI performance is irrelevant.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
This section is not applicable. As mentioned above, the device is a medical implant, not an algorithm or AI system.
7. The Type of Ground Truth Used
The ground truth used for these tests is based on:
- Objective material property measurements against established industry standards (ASTM F-648, modified ASTM D2765-90).
- Quantitative analytical techniques such as FTIR (Fourier-transform infrared spectroscopy) for oxidation and ESR (Electron Spin Resonance) for free radicals.
- Standardized in vitro wear simulation using a hip wear simulator.
Essentially, the "ground truth" is derived from scientific and engineering measurements and established test methods.
8. The Sample Size for the Training Set
This section is not applicable. This is not an AI/machine learning device, so there is no concept of a "training set." The materials themselves are manufactured and tested, not "trained."
9. How the Ground Truth for the Training Set was Established
This section is not applicable, as there is no training set for this device.
§ 888.3350 Hip joint metal/polymer semi-constrained cemented prosthesis.
(a)
Identification. A hip joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace a hip joint. The device limits translation and rotation in one or more planes via the geometry of its articulating surfaces. It has no linkage across-the-joint. This generic type of device includes prostheses that have a femoral component made of alloys, such as cobalt-chromium-molybdenum, and an acetabular resurfacing component made of ultra-high molecular weight polyethylene and is limited to those prostheses intended for use with bone cement (§ 888.3027).(b)
Classification. Class II.