(368 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:
- · Non-inflammatory degenerative joint disease such as osteoathritis, avascular necrosis, ankylosis, protrusio acetabuli, and painful hip dysplasia;
- · Inflammatory degenerative joint disease such as rheumatoid arthritis;
- . Correction of function deformity;
- Revision procedures where other treatments or devices have failed; and .
- · Treatment of nonunion, femoral neck, and trochanteric fractures of the proximal femur with head involvement that are unmanageable using other techniques.
The U1 Hip System is designated as a total hip joint replacement. It is a modular type of product system. The followings are the major design features.
Femoral Stem: The component has seven sizes of options, tri- wedge design, straight stem, 1340 neck-stem angle, a Morse type taper to receive modular heads, porous coated surface on proximal portion and satin finished on distal. There are w/ and w/o calcar collar designs. This device is produced from cast Co-Cr-Mo alloy (ASTM F75).
Femoral Head; The head diameter is 26mm. There are four adjustments of options. Std. +3, +6, +9, respectively. It is fabricated from wrought Co-Cr-Mo alloy bars (ASTM F1537) by machining.
Acetabular Component: This device has ten sizes of options, hemispherical design, porous coated surface on metallic shell, clustered bone screw holes, spherical screw holes for variable screw locking angle, PMMA cement plug, easy snap-in and take out mechanism, 16 options for angle adjustment, minimum 4.33mm thickness of UHMWPE liner. The metallic shell is produced from cast Co-Cr-Mo alloy (ASTM F75). The plastic liner is machined from extruded UHMWPE bars (ISO 5834/1)
Bone Screw: This device is a 6.5 mm cancellous bone screw. It has six lengths of options (15 mm ~ 40 mm), and has a shallow screw head.
The provided document describes the predicate device information contained in a 510(k) Pre-market Notification for the U1 Hip System. It is not an AI/ML device, therefore, the information requested about acceptance criteria, study details, and AI/ML specific evaluations (like human reader improvement with AI, standalone performance, training sets, etc.) is not applicable to this document.
However, I can extract the closest relevant information from the document regarding the device's performance justification:
1. Table of Acceptance Criteria and Reported Device Performance
| Feature/Criterion | Acceptance Level (Implied/Predicate-based) | Reported Device Performance |
|---|---|---|
| U1 Hip System vs. Predicate (DePuy AML® Hip Prosthesis) | Essential Equivalence | Achieves essential equivalence in design concepts for femoral components (established by FEA). |
| Porous Coating Static Tensile and Shear Strength | > 20 MPa | More than 20 MPa |
| Porous Coating Volume Porosity | Between 30% and 70% | Between 30% and 70% |
| Porous Coating Average Pore Size | Between 100 and 1000 microns | Between 100 and 1000 microns |
| Porous Coating Thickness | Between 500 and 1,500 microns | Between 500 and 1,500 microns |
2. Sample size used for the test set and the data provenance
- Sample Size: Not applicable. This device is not an AI/ML device that uses a "test set" in the conventional sense of data samples. The evaluation was based on engineering analysis and material properties.
- Data Provenance: Not applicable.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Not applicable. This is not an AI/ML device.
4. Adjudication method for the test set
- Not applicable. This is not an AI/ML device.
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 not an AI/ML device.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Not applicable. This is not an AI/ML device.
7. The type of ground truth used
- The "ground truth" in this context is the safety and effectiveness profile of the predicate device (DePuy AML® Hip Prosthesis), as well as established biomechanical and material science principles and standards (e.g., ASTM F75 for Co-Cr-Mo alloy, ISO 5834/1 for UHMWPE). The U1 Hip System aims to demonstrate substantial equivalence to this predicate.
8. The sample size for the training set
- Not applicable. This is not an AI/ML device.
9. How the ground truth for the training set was established
- Not applicable. This is not an AI/ML device.
Study That Proves the Device Meets Acceptance Criteria:
The "study" that proves the device meets acceptance criteria, in this context, is primarily articulated through Finite Element Analysis (FEA) and material property testing:
-
FEA Study:
- The U1 stem was analyzed using finite element analysis.
- Finding: The FEA results indicated that the U1 stem's performance (relative motion, load transfer) was "somewhat less sensitive to changes in friction condition than they are for the more extensively coated AML" (the predicate device).
- Conclusion: This analysis established the "essential equivalence of the design concepts for the U1 and AML femoral components." This implies that the U1 design is considered to perform similarly and acceptably to the established predicate.
-
Material Property Testing of Porous Coating:
- Tests: Static tensile and shear strength, volume porosity, average pore size, and porous coating thickness were tested.
- Findings: The reported values (more than 20MPa for strength, 30-70% for volume porosity, 100-1000 microns for average pore size, and 500-1500 microns for thickness) meet or exceed the implied acceptance criteria for such coatings, which are typically based on established medical device standards and the performance of successful predicate devices. The document explicitly states these findings.
Overall Justification:
The substantial equivalence was based on features comparable to the predicate device, including the Co-Cr-Mo alloy substrate, straight stem type, beaded porous coated surface on the proximal portion of the stem and acetabular cup, and Morse taper locked with heads. The FEA and material testing provided the engineering and scientific basis to support this comparability and substantial equivalence.
§ 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.