(111 days)
The POLARSTEM Collared and Valgus Stem with Ti/HA (INTEGRATION-PLUS) is indicated for:
- Advanced degeneration of the hip joint as a result of degenerative, post-traumatic or rheumatoid arthritis.
- Fracture or avascular necrosis of the femoral head .
- . Failure of previous hip surgery: joint reconstruction, internal fixation, arthrodesis, hemiarthroplasty, surface replacement arthroplasty, or total hip replacement
The POLARSTEM with Ti/HA is intended for single use only and is to be implanted without bone cement.
The POLARSTEM Collared (Standard and Lateral) and Valgus femoral stems designed for noncemented use are made of a titanium alloy (Ti-6Al-4V) with a fully porous titanium plasma/hydroxyapatite coating (Ti/HA). The design incorporates a highly polished neck area, distal grooves to increase rotational stability, and a 12/14 taper. The collared and valgus femoral stems are substantially equivalent to the POLARSTEM standard and lateral femoral stem with Ti/HA cleared via K130728.
The provided document pertains to a 510(k) premarket notification for a hip joint femoral stem (POLARSTEM Collared and Valgus Femoral Stem with Ti/HA). This type of submission is a regulatory pathway for medical devices that are "substantially equivalent" to a legally marketed predicate device.
Unlike studies for AI/software as a medical device (SaMD) or diagnostic devices, a 510(k) for a physical implantable device like a hip stem does not typically involve the acceptance criteria, sample sizes for test sets, expert ground truth, adjudication methods, MRMC studies, or standalone performance metrics that are common for AI/SaMD studies. Instead, the "acceptance criteria" here refers to demonstrating substantial equivalence to a predicate device through engineering and mechanical testing.
Here's an attempt to answer your questions based on the provided document, interpreting "acceptance criteria" and "study" within the context of a 510(k) for an orthopedic implant:
1. A table of acceptance criteria and the reported device performance
For a 510(k) of an orthopedic implant, acceptance criteria are generally met by demonstrating that the new device performs similarly or better than a predicate device in specific mechanical and material tests, ensuring it is safe and effective for its intended use. The document confirms that the device meets these criteria by being "substantially equivalent" to its predicate.
| Acceptance Criterion (Implicit) | Reported Device Performance (Achieved) |
|---|---|
| Withstand expected in vivo loading without failure. | Capable of withstanding expected in vivo loading without failure (based on mechanical data and testing). |
| Comparable mechanical characteristics to predicate device. | Mechanical data indicates substantial equivalence to the predicate (K130728). |
| Comparable material composition and properties to predicate. | The Ti/HA coating is identical in composition, properties, and manufacturing location to the predicate. Device is made of titanium alloy (Ti-6Al-4V). |
| Comparable indications for use to predicate. | Indications for use are substantially equivalent to the predicate, with minor clarifications. |
| Biocompatibility and material safety (implied by Ti/HA coating). | Surface characterization (physical, chemical, mechanical) discussed in Ti/HA Coating Master File MAF - 1762 Amendment 1 and 2 (not included in 510(k) summary but part of overall safety). |
2. Sample sizes used for the test set and the data provenance
The document does not specify exact sample sizes for each mechanical test (e.g., number of stems tested for fatigue). It refers to "mechanical data" and "tests," implying standard engineering test methods using a sufficient number of samples according to relevant ASTM or ISO standards for orthopedic implants.
- Sample Size for Test Set: Not explicitly stated for each test, but implied to be sufficient for engineering characterization according.
- Data Provenance: The tests are performed by the manufacturer, Smith & Nephew, Inc., and the Ti/HA coating manufacturing is at Smith & Nephew AG. This is prospective testing performed for regulatory submission. Data origin is within a controlled manufacturing/testing environment, likely in the US or Europe given the company's global presence.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
This concept is not applicable in the context of a 510(k) for a physical implant. "Ground truth" for mechanical properties is established through standardized engineering tests, not expert consensus on interpretations of medical data. The "experts" involve engineers and material scientists who design and test the device against established performance benchmarks and regulatory standards.
4. Adjudication method for the test set
Not applicable. Adjudication is relevant for subjective assessments (e.g., medical image interpretation). Mechanical testing results are objective measurements (e.g., breaking strength, fatigue cycles) that are compared against predefined limits or predicate device performance.
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. MRMC studies are used for diagnostic devices involving human interpretation of medical data, particularly in the context of AI/SaMD. This document is for a physical orthopedic implant.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Not applicable. This device is a physical implant, not an algorithm or software.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
For this type of device, the "ground truth" for proving safety and effectiveness (i.e., substantial equivalence) is based on:
- Engineering and Mechanical Test Standards: Adherence to recognized standards (e.g., ASTM, ISO) for implant materials and performance (e.g., fatigue strength, range of motion, material properties).
- Predicate Device Performance: Direct comparison of the new device's performance against that of the legally marketed predicate device.
- Material Characterization: Ensuring the materials meet established specifications for biocompatibility and mechanical properties, often referenced via master files (like the Ti/HA Coating Master File MAF - 1762 mentioned).
8. The sample size for the training set
Not applicable. There is no "training set" in the machine learning sense for this device.
9. How the ground truth for the training set was established
Not applicable. There is no "training set" for this device.
§ 888.3353 Hip joint metal/ceramic/polymer semi-constrained cemented or nonporous uncemented prosthesis.
(a)
Identification. A hip joint metal/ceramic/polymer semi-constrained cemented or nonporous uncemented prosthesis is a device intended to be implanted to replace a hip joint. This device limits translation and rotation in one or more planes via the geometry of its articulating surfaces. It has no linkage across-the-joint. The two-part femoral component consists of a femoral stem made of alloys to be fixed in the intramedullary canal of the femur by impaction with or without use of bone cement. The proximal end of the femoral stem is tapered with a surface that ensures positive locking with the spherical ceramic (aluminium oxide, A12 03 ) head of the femoral component. The acetabular component is made of ultra-high molecular weight polyethylene or ultra-high molecular weight polyethylene reinforced with nonporous metal alloys, and used with or without bone cement.(b)
Classification. Class II.