(90 days)
The Mpact® Acetabular System is intended for cementless use in total hip arthroplasty and in primary or revision surgery. The patient should be skeletally mature. The patient's condition should be due to one or more of:
- Severely painful and/or disabled joint: as a result of osteoarthritis, post-. traumatic arthritis, rheumatoid arthritis or psoriactic arthritis, congenital hip dysplasia, or ankylosing spondylitis.
- . Avascular necrosis of the femoral head.
- Acute traumatic fracture of the femoral head or neck. .
- . Failure of previous hip surgery: joint reconstruction, internal fixation, arthrodesis, hemiarthroplasty, surface replacement arthroplasty, or total hip replacement where sufficient bone stock is present.
The Mpact® Acetabular System components are designed to be used with the Medacta Total Hip Prosthesis System. The Medacta Total Hip Prosthesis system includes the Quadra S, H, R, and C Stems and CoCrMo and ceramic ball heads (K072857, K073337, K080885, K082792, and K083558). The AMIStem femoral stems also work with the Medacta Total Hip Prosthesis System (K093944). The Medacta Total Hip Prosthesis System is a total hip replacement system consisting of the femoral stem made of metal, a modular femoral head made of metal or ceramic, and acetabular components. The Mpact® Acetabular System acetabular components that are the subject of this 510(k) consist of a metal cup made of Titanium alloy and a fixed liner that is made of ultra-high molecular weight polyethylene (UHMWPE) or HighCross® highly crosslinked ultra-high molecular weight polyethylene (HXUHMWPE).
The metal acetabular component or shell is machined from titanium alloy (Ti-6Al-4V) conforming to ISO 5832-3 and ASTM F136. The outside of the metal component is a hemispherical design. The outer surface of the metallic cup has a porous coating called TiGrowth made of pure titanium conforming to ASTM F1580. The polyethylene liner is a fixed liner made of UHMWPE conforming to ISO 5834-2. The liner has a minimum thickness of at least 5.5 mm when made of standard UHMWPE and of least 4 mm when made of HXUHMWPE.
If supplemental bone screw fixation is needed, cancellous bone screws made of titanium alloy (Ti-6Al-4V) can be inserted through screw holes. Screw hole covers made of titanium alloy (Ti-6Al-4V) are also provided for the central hole.
Also included in this submission are additional Medacta ball heads made of CoCrMo in the 40 mm diameter to augment the Medacta ball heads previously cleared in K072857, K073337 and K080885.
The metal acetabular component is available in 11 sizes and is for use with polyethylene liners that accept both CoCrMo with diameters of 22, 28, 32, and 36 mm and MectaCer BIOLOX® forte Ceramic ball heads with diameters of 28, 32, and 36 mm. They also work with the Medacta 40 mm CoCrMo ball heads. The fixed liners are available in both flat and hooded options in a range of sizes.
All the Mpact® Acetabular System components and Medacta 40 mm ball heads are supplied sterile in single-use individual packages.
Here's an analysis of the provided text regarding the acceptance criteria and study to prove the device meets them, structured as requested:
Device: Mpact® Acetabular System and Medacta 40 mm Ball heads (specifically focusing on HighCross™ highly crosslinked UHMWPE liners due to the detailed wear claim)
Acceptance Criteria and Reported Device Performance
| Acceptance Criteria Category | Acceptance Criteria (from text) | Reported Device Performance (from text) |
|---|---|---|
| Wear | Not explicitly stated with a numerical target in this section, but the context implies meeting a performance level comparable to predicates or established standards for such devices in terms of wear generation. The study design follows ISO 14242-1. | HighCross™ UHMWPE Liners: |
- Average gravimetric wear rate: 6.28 mg +/- 1.68 mg per million cycles
- Average volumetric wear rate: 7.8 mm³ per million cycles
- Average total wear for 5 million cycles: 31.54 mg (for 40 mm inner diameter liners)
(Note: "The in vitro hip wear simulator tests have not been shown to quantitatively predict clinical wear performance.") |
| Mechanical Stability | Pre-defined acceptance criteria for:
- Push out
- Lever out
- Rotational stability of the modular connection of the fixed liner to the metal shell | "The testing met all acceptance criteria" (referring to push out, lever out, and rotational stability). No specific numerical values are provided for these tests in the summary. |
| Coating Validation | Pre-defined acceptance criteria for coating validation. | "The testing met all acceptance criteria" (referring to coating validation). No specific details provided. |
| Shell Deformation | Pre-defined acceptance criteria for metal shell deformation resistance during impaction. | "The testing met all acceptance criteria" (referring to metal shell deformation resistance). No specific details provided. |
| Range of Motion | Pre-defined acceptance criteria for range of motion. | "The testing met all acceptance criteria" (referring to range of motion). No specific details provided. |
| Bone Screw Testing | Pre-defined acceptance criteria for bone screw testing. | "The testing met all acceptance criteria" (referring to bone screw testing). No specific details provided. |
| Substantial Equivalence | Demonstrating substantial equivalence to predicate devices in indications for use, design, materials, coatings, and technological characteristics. | Concluded to be substantially equivalent to predicates (DePuy Pinnacle®, Smith & Nephew REFLECTION 3, Medacta Bone Screws, Versafitcup® Double Mobility, Apex Modular heads) based on indications for use and technological characteristics, and for wear performance of the HighCross® UHMWPE liners. |
Study Information
Due to the nature of this submission (510(k) summary for an orthopedic implant), the studies described are in vitro performance tests, not clinical efficacy studies with human subjects. Therefore, some requested categories (like "adjudication method" or "effect size of human readers") are not applicable.
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Sample size used for the test set and the data provenance:
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Wear Testing:
- Sample Size: 3 liners (for the HighCross™ highly crosslinked UHMWPE liners).
- Data Provenance: In-vitro mechanical testing conducted by the manufacturer (Medacta International SA), likely at their facilities or a contracted lab. Country of origin not explicitly stated, but the manufacturer is based in Switzerland. The testing is retrospective in the sense that it's performed after design finalization to demonstrate performance characteristics.
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Other Performance Testing (Push out, Lever out, Rotational stability, Coating validation, Shell deformation, Range of motion, Bone screw testing):
- Sample Size: Not explicitly stated, but "worst case component size and option/design" were tested.
- Data Provenance: In-vitro mechanical testing conducted by the manufacturer. Retrospective.
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts: Not applicable. These are in vitro mechanical tests, not studies requiring expert interpretation of medical images or clinical outcomes. The "ground truth" is defined by the physical properties and performance characteristics measured according to established engineering standards.
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Adjudication method for the test set: Not applicable, as this refers to expert review of clinical data or images, which is not part of this in vitro performance testing.
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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/imaging device.
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If a standalone (i.e. algorithm only without human-in-the-loop performance) was done: Not applicable. This is a medical implant, not an algorithm.
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The type of ground truth used:
- Wear Testing: Gravimetric and volumetric wear measurements, defined by physical changes (mass loss, volume loss) and measured using precise laboratory techniques (e.g., weighing, 3D profiling).
- Other Performance Testing: Engineering specifications and mechanical properties (e.g., force required for push-out, deformation limits), measured according to international standards (e.g., ISO, ASTM).
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The sample size for the training set: Not applicable. This is not a machine learning or AI device that requires a training set.
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How the ground truth for the training set was established: Not applicable.
§ 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.