(28 days)
This device is indicated in hip arthroplasty for reduction or relief of pain and/or improved hip function in skeletally mature patients with the following conditions:
For use as a Total Hip Replacement
- Painful, disabling joint disease of the hip resulting from: degenerative arthritis, rheumatoid arthritis, post-traumatic arthritis or late stage avascular necrosis.
- Revision of previous unsuccessful femoral head replacement, cup arthroplasty or other procedure.
- Clinical management problems where arthrodesis or alternative reconstructive techniques are less likely to achieve satisfactory results.
For use as a Bipolar Hip Replacement
- Femoral head/neck factures or non-unions.
- Aseptic necrosis of the femoral head.
- Osteo-, rheumatoid, and post-traumatic arthritis of the hip with minimal acetabular involvement or distortion.
Cemented stem is designed for cemented use only.
The U2 Hip System for hip arthroplasty is a metal/polymer/metal semi-constrained prosthesis with femoral components and acetabular components. The femoral components are composed of a ball mechanical locked with a stem by means of a Morse taper, while the acetabular components are composed of an highly crosslinked ultra - high - molecular - weight - polyethylene articulating bearing surface fixed in a metal shell. Components of this premarket notification include the following components:
- Ti Porous Coated Cup
- XPE Cup Liner
- 32 mm and 36 mm Femoral Head
- U2 Hip Stem, Press-fit
- U2 Hip Stem, Cemented
The titanium bar (ASTM F136) was forged into a net-shape of acetabular cup and then the forged part was machined into the final shape of Ti Porous Coated Cup. The outer surface is porous coated with three layers of CP Ti beads (ASTM F1580). XPE Cup Liner is manufactured from highly crosslinked UHMWPE which conform to ASTM F2565 and the UHMWPE raw material is in accordance with ASTM F648 and ISO 5834. The first series of XPE Cup Liner with the sizes of 44 to 80 mm has an inner diameter of 28 mm. The second series with the sizes of 50 to 80 mm have an inner diameter of 32 mm. The third series with the sizes from 54 to 80 mm have an inner diameter of 36 mm. The 32 and 36 mm Femoral Head is manufactured from CoCrMo alloy (ASTM F1537) with neck length of -3, +0, +5, and +10 mm. U2 Press-fit Stem is manufactured from titanium alloy (ASTM F620) which is intended for cementless fixation within the prepared femoral canals of patients requiring hip arthroplasty. U2 Cemented Hip Stem manufactured from forging CoCrMo alloy (ASTM F799) is intended for cement fixation. Moreover, this device is available to use with an accessory, called "Cement Restrictor, Full PE" made of Ultra-High Molecular Weight Polyethylene (ASTM F648).
The Ti Porous Coated Cup will be used with 510k cleared cup liner of the U2 Acetabular Component (K050262) and currently submission XPE Cup Liner. As using with the existing cup liner (K050262), the Ti Porous Coated Cup may be used with 26 mm and 28 mm Femoral Head (K994078 and K022520) and 28 mm Ceramic Femoral Head (K103479). As using with currently submission XPE Cup Liner, this component may be used with currently submission 32 mm and 36mm Femoral Head, the 28 mm Femoral Head (K022520) and 28 mm and 32 mm Ceramic Femoral Head (K103479). Besides, XPE Cup Liner may also be used with existing U2 Acetabular Cup (K050262). The 32 mm and 36 mm Femoral Head may also be used with U2 Bipolar Implant (K101670), Revision Stem (K062978) and current submission Cemented Stem and Press-fit Stem.
The Press-fit Stem and Cemented Stem will be used with currently submission 32mm and 36 mm metal Femoral Head and may be used with 26 mm and 28 mm metal Femoral Head (K994078 and K022520). The Press-fit Stem which made from Ti alloy can also be used with Ceramic Femoral Head (K103479).
The provided text describes the U2 Hip System, a semi-constrained hip prosthesis. It details the device components, materials, and indications for use. The document focuses on demonstrating substantial equivalence to predicate devices through comparisons of design, operational principles, material composition, and extensive bench performance tests. There is no information about acceptance criteria or a study proving the device meets acceptance criteria in the sense of clinical performance or diagnostic accuracy. Instead, the "performance test - bench" section outlines mechanical tests conducted to ensure the device's safety and effectiveness regarding its physical properties and mechanical integrity.
Here's an analysis based on the provided text, addressing the user's questions where applicable, and noting where information is not available:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state "acceptance criteria" as pass/fail thresholds for clinical performance or diagnostic accuracy. Instead, it describes mechanical tests performed to demonstrate the device's ability to withstand expected in vivo loading. The "reported device performance" is that these tests were performed and a "review of the mechanical data indicates that the U2 Hip System is capable of withstanding expected in vivo loading without failure." No specific numerical results of these tests and their comparison against predefined limits are provided in this summary.
Here's a summary of the tests performed and the general conclusion:
| Test Performed | Reported Device Performance |
|---|---|
| Locking Strength of XPE Cup Liner per ASTM F1820 | Mechanical data indicates capability of withstanding expected in vivo loading without failure. |
| Wear Simulation Test of XPE Cup Liner per ISO 14242-1 | Mechanical data indicates capability of withstanding expected in vivo loading without failure. |
| Range of Motion for XPE Cup Liner and 32 and 36 mm Femoral Head by CAD simulation | Mechanical data indicates capability of withstanding expected in vivo loading without failure. |
| Femoral Head Disassembly loads for the Subject Stem per ASTM F2009 | Mechanical data indicates capability of withstanding expected in vivo loading without failure. |
| Stem Fatigue Test for Press-fit Stem and Cemented Stem with Torsion per ISO 7206-4 and ASTM F1612 | Mechanical data indicates capability of withstanding expected in vivo loading without failure. |
| Neck Fatigue Test for Press-fit Stem and Cemented Stem with Torsion per ISO 7206-6 | Mechanical data indicates capability of withstanding expected in vivo loading without failure. |
| Evaluation of modified surface treatment (SEM, shear fatigue, static shear, static tensile, taber abrasion resistance) | Mechanical data indicates capability of withstanding expected in vivo loading without failure. |
| Characterization of material properties of XPE cup liner (tensile, ultimate load, Izod impact, fatigue crack propagation, thermal, residual free radicals, swell ratio, oxidation index, trans-vinylene index) | Mechanical data indicates capability of withstanding expected in vivo loading without failure. |
The document states: "A review of these tests has demonstrated that there are no new issues related to the safety and effectiveness of the subject devices."
2. Sample size used for the test set and the data provenance
Not applicable. The study described is a series of bench performance tests on the device's components, not a clinical trial or a study involving human subjects or data. Therefore, there is no "test set" in the context of patient data.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
Not applicable. This is a medical device (hip prosthesis), and the "study" involves mechanical testing, not interpretation of data by experts for ground truth establishment.
4. Adjudication method (e.g., 2+1, 3+1, none) for the test set
Not applicable. This is a medical device (hip prosthesis) and the "study" involves mechanical testing.
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 document pertains to a medical device (hip prosthesis), not an AI algorithm or a diagnostic tool that would involve human readers.
6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done
Not applicable. This document pertains to a medical device (hip prosthesis), not an algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
Not applicable in the conventional sense of diagnostic accuracy studies. For mechanical tests, the "ground truth" is defined by the objective physical properties and performance characteristics as measured against established ASTM and ISO standards for medical implants. The tests themselves are designed to evaluate whether the components meet these engineering standards for safety and effectiveness.
8. The sample size for the training set
Not applicable. There is no "training set" as this is not an AI/machine learning algorithm.
9. How the ground truth for the training set was established
Not applicable. There is no "training set" as this is not an AI/machine learning algorithm.
Additional Information from the document:
- Clinical Data: "Clinical data was not needed to support the safety and effectiveness of the subject devices." This implies that the substantial equivalence argument was entirely based on non-clinical (bench) testing and comparison to predicate devices.
- Regulatory Basis: The 510(k) was prepared in accordance with several FDA guidance documents for hip joint prostheses and orthopedic implants, reinforcing that the testing conducted (as detailed in the "Performance Test - Bench" section) is the accepted method for demonstrating safety and effectiveness for this type of device.
§ 888.3358 Hip joint metal/polymer/metal semi-constrained porous-coated uncemented prosthesis.
(a)
Identification. A hip joint metal/polymer/metal semi-constrained porous-coated uncemented 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 has a femoral component made of a cobalt-chromium-molybdenum (Co-Cr-Mo) alloy or a titanium-aluminum-vanadium (Ti-6Al-4V) alloy and an acetabular component composed of an ultra-high molecular weight polyethylene articulating bearing surface fixed in a metal shell made of Co-Cr-Mo or Ti-6Al-4V. The femoral stem and acetabular shell have a porous coating made of, in the case of Co-Cr-Mo substrates, beads of the same alloy, and in the case of Ti-6Al-4V substrates, fibers of commercially pure titanium or Ti-6Al-4V alloy. The porous coating has a volume porosity between 30 and 70 percent, an average pore size between 100 and 1,000 microns, interconnecting porosity, and a porous coating thickness between 500 and 1,500 microns. The generic type of device has a design to achieve biological fixation to bone without the use of bone cement.(b)
Classification. Class II.