VERILAST WEAR CLAIMS FOR THE LEGION PRIMARY KNEE SYSTEM
Device Facts
| Record ID | K093746 |
|---|---|
| Device Name | VERILAST WEAR CLAIMS FOR THE LEGION PRIMARY KNEE SYSTEM |
| Applicant | Smith & Nephew, Inc. |
| Product Code | JWH · Orthopedic |
| Decision Date | Apr 14, 2010 |
| Decision | SESE |
| Submission Type | Traditional |
| Regulation | 21 CFR 888.3560 |
| Device Class | Class 2 |
| Attributes | Therapeutic |
Indications for Use
Total knee components are indicated for rheumatoid arthritis; post-traumatic arthritis, osteoarthritis, or degenerative arthritis in older patients whose age, weight, and activity level are compatible with an adequate long-term result; failed osteotomies, unicompartmental replacement, or total knee replacement. Posterior stabilized knee systems are designed for use in patients in primary and revision surgery, where the anterior and posterior cruciate ligaments are absent or incompetent and the collateral ligaments remain intact. Smith & Nephew, Inc. Legion Primary Knee components are indicated for use only with cement and are single use devices.
Device Story
The LEGION Primary Knee System is a total knee prosthesis consisting of an Oxinium femoral component and a 7.5 Mrad cross-linked polyethylene (XLPE) articular insert. The device is intended for cemented, single-use implantation in patients undergoing total knee arthroplasty. This submission specifically establishes long-term in vitro wear claims for the existing implant components. The device is used by orthopedic surgeons in a clinical/surgical setting. The system functions as a mechanical bearing couple; the Oxinium/XLPE interface is designed to exhibit low wear characteristics. Clinical decision-making is supported by the established safety and effectiveness of the existing components, with the new wear claims providing information on long-term durability. The patient benefits from a reduced rate of wear, potentially extending the lifespan of the knee replacement.
Clinical Evidence
No clinical data was used to support the safety and effectiveness of the device. Evidence is based on in vitro knee simulator wear testing, which demonstrated that the OXINIUM/XLPE bearing couple exhibits low wear characteristics compared to a control system. The document notes that in vitro wear simulation results have not been proven to quantitatively predict clinical wear performance.
Technological Characteristics
System comprises Oxinium (oxidized zirconium) femoral components and 7.5 Mrad cross-linked polyethylene (XLPE) articular inserts. Designed as a semi-constrained, cemented, single-use total knee prosthesis. No new materials or fundamental technological changes; modifications include geometric adjustments to the femoral box and condyles. Connectivity: N/A. Sterilization: Not specified.
Indications for Use
Indicated for patients with rheumatoid, post-traumatic, or degenerative arthritis requiring total knee replacement, or those with failed prior osteotomies or unicompartmental replacements. Posterior stabilized systems indicated for primary or revision surgery where cruciate ligaments are absent/incompetent but collateral ligaments remain intact. For use in older patients with compatible age, weight, and activity levels.
Regulatory Classification
Identification
A knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace a knee 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 includes prostheses that have a femoral component made of alloys, such as cobalt-chromium-molybdenum, and a tibial component or components and a retropatellar resurfacing component made of ultra-high molecular weight polyethylene. This generic type of device is limited to those prostheses intended for use with bone cement (§ 888.3027).
Predicate Devices
- Genesis II & Profix Zirconium Femoral Knee Components (K962557)
- Crosslinked Polyethylene Articular Inserts (K071071)