(108 days)
Wright Medical total hip systems are indicated for use in total hip arthroplasty for reduction or relief of pain and/or improved hip function in skeletally mature patients.
Indications for Use
- non-inflammatory degenerative joint disease such as osteoarthritis, avascular necrosis, 1. ankylosis, protrusio acetabuli, and painful hip dysplasia;
-
- inflammatory degenerative joint disease such as rheumatoid arthritis;
- correction of functional deformity; and, 3.
-
- revision procedures where other treatments or devices have failed
The PROFEMUR® Z Revision Hip Stem is intended for cementless hip arthroplasty.
- . Cementless modular stems
- Available in 9 sizes .
- Manufactured from Titanium alloy with a heavy grit blasted surface .
The subject device is available in 9 sizes (from size 3 to 11). Although the proximal geometries are identical to the predicate from size 3-9, the distal stem length has increased, with two larger sizes (10 and 11) introduced.
The provided text describes a 510(k) premarket notification for a medical device, the PROFEMUR® Z Revision Hip Stem. It does not contain information about acceptance criteria, device performance, or a study demonstrating the device meets such criteria in the way typically associated with AI/software-as-a-medical-device (SaMD) clearances.
Instead, this document focuses on demonstrating substantial equivalence to existing legally marketed predicate devices, which is the cornerstone of the 510(k) pathway for many Class II medical devices.
Here's an analysis based on the provided text, addressing the points where information is available and noting where it is not applicable or not provided:
1. Table of Acceptance Criteria and Reported Device Performance
Not applicable in the context of this 510(k) submission. This document does not present acceptance criteria for a specific performance metric (like accuracy, sensitivity, specificity for an AI algorithm) nor does it report such performance. The clearance is based on substantial equivalence, not on meeting predefined performance thresholds from a clinical trial in humans.
2. Sample Size Used for the Test Set and Data Provenance
Not applicable. There was no "test set" in the context of clinical performance evaluation for this 510(k). The evaluation involved nonclinical testing of the device hardware.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
Not applicable. There was no ground truth for a test set established by experts in this submission.
4. Adjudication Method for the Test Set
Not applicable.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and Effect Size
No. A MRMC study is typically for evaluating the impact of AI on human reader performance, which is not relevant for this revision hip stem.
6. If a Standalone (Algorithm Only Without Human-in-the-Loop) Performance Study Was Done
Not applicable. This device is a physical hip stem, not an algorithm.
7. The Type of Ground Truth Used
Not applicable.
8. The Sample Size for the Training Set
Not applicable. Again, this is a physical device, not an AI/ML algorithm that requires a training set.
9. How the Ground Truth for the Training Set Was Established
Not applicable.
Summary of Device Evaluation for K121221 (PROFEMUR® Z Revision Hip Stem):
- Acceptance Criteria & Performance: The acceptance criteria for this 510(k) submission revolved around demonstrating substantial equivalence to predicate devices. This means proving that the new device is as safe and effective as a legally marketed device. The "performance" assessment was primarily through nonclinical testing (mechanical fatigue evaluation) and comparison of design features and materials to predicate devices.
- Nonclinical Testing: The PROFEMUR® Z Revision Hip Stems were tested in distal and proximal fatigue evaluation per the loading regimen prescribed by ISO 7206-4, -6 and -8. The assumption is that the device met the requirements of these ISO standards, thereby demonstrating acceptable mechanical performance equivalent to other devices cleared under these standards. The specific results (cycles to failure, load limits, etc.) are not detailed in this summary but would have been part of the full submission.
- Study Type: The submission relies on nonclinical testing (fatigue evaluation) and a comparative analysis of design features, materials, and intended use against predicate devices (STEM Hip Replacement System K021346 and PRESERVE HIP STEM K112080).
- Clinical Data: Explicitly stated: "Clinical data was not provided for the class II hip stem." This indicates no human clinical trials were performed for this specific submission to demonstrate safety and effectiveness, as it was deemed unnecessary due to substantial equivalence.
- Ground Truth/Training Data: Not applicable as this is a physical implant and not an AI/ML algorithm.
Conclusion from the document: The FDA found the PROFEMUR® Z Revision Hip Stem to be substantially equivalent to its predicate devices based on:
* Identical indications for use.
* Similar design features and materials.
* The same fundamental scientific technology.
* Adequate support from "substantial equivalence information, materials information, and analysis data provided within this Premarket Notification."
This 510(k) successfully navigated the regulatory pathway by demonstrating that the changes were minor enough (e.g., increased distal stem length, two new sizes) and supported by nonclinical mechanical testing, making a full clinical trial for performance unnecessary.
§ 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.