(57 days)
Xerxes Hip Stems, when used with cleared and compatible Signature Orthopaedics hip replacement components, are intended to replace a hip joint where bone stock is sufficient to support the implant. When a surgeon has selected prosthetic replacement as the preferred treatment, the devices are indicated for:
- Non-inflammatory degenerative joint disease including osteoarthritis or avascular necrosis
- Inflammatory joint disease including rheumatoid arthritis
- Correction of functional deformity including congenital hip dysplasia
- Traumatic injury involving the hip joint including traumatic arthritis or femoral head or neck fracture
- Failed previous hip surgery including internal fixation or joint fusion, reconstruction, hemiarthroplasty, surface replacement, or total replacement.
Xerxes Hip femoral stems are intended for cementless fixation only. The Xerxes Hip System is intended for use with Logical, World Acetabular System and Signature Orthopaedics' Femoral Heads.
Xerxes Hip when used with constrained liner components is indicated particularly for patients at high risk of hip dislocation due to history of prior dislocation, bone loss, joint or soft tissue laxity, neuromuscular disease, or intraoperative instability.
Xerxes™ Hip Stem is manufactured from forged titanium alloy (Ti6Al4V) as per ISO 5832-3 and ASTM F136. The Xerxes™ Hip Stem is an anatomical stem with a 5° anteversion neck and a 250 mm radius curvature on the stem body. The stem has three different surface and/or coating areas. The distal tip portion is colour anodised, polished, and rounded to aid in the insertion and avoiding distal interference. The remainder of the stem below its resection line is coated for cementless fixation. The middle portion of the stem is coated with a single layer of hydroxyapatite coating, as per ISO 13779-2 while the proximal portion is coated with an additional layer of titanium plasma spray as per ASTM F1580.
This document describes a 510(k) premarket notification for the Xerxes Hip Stem, a medical device. It does not contain information about the acceptance criteria or a study proving that the device meets such criteria in the way one might expect for an AI/CADe device.
The document focuses on demonstrating substantial equivalence to predicate devices through technological characteristics and non-clinical performance data, rather than detailing a study that measures new performance metrics against specific acceptance thresholds for a novel device.
However, I can extract the information provided regarding the "performance data" in the context of demonstrating substantial equivalence:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state "acceptance criteria" for novel device performance. Instead, it lists non-clinical tests conducted to verify the performance of the Xerxes Hip Stem is adequate for anticipated in-vivo use and support substantial equivalence. The "performance" here refers to satisfying established standards or engineering expectations for hip stems, rather than a quantifiable diagnostic accuracy or similar metric for an AI device.
| Test Conducted | Standard/Method Referenced | Reported Device Performance (Implied "Meets Criteria") |
|---|---|---|
| Range of Motion testing | ISO 21535 | Adequate for anticipated in-vivo use |
| Stem and Neck Fatigue Finite Element Analysis | ASTM F2996 | Adequate for anticipated in-vivo use |
| Stem and Neck Fatigue Testing | ISO 7206-4 and ISO 7206-6 | Adequate for anticipated in-vivo use |
| Pyrogenicity and Endotoxin Testing | AAMI ST72 | Adequate for anticipated in-vivo use |
2. Sample Size for Test Set and Data Provenance
Not applicable. This device is a mechanical implant (hip stem), and the testing described is non-clinical performance and fatigue testing, not a study involving patient data or images.
3. Number of Experts and Qualifications for Ground Truth
Not applicable. Ground truth as typically defined for a diagnostic device or AI algorithm is not relevant for the non-clinical mechanical testing of a hip stem.
4. Adjudication Method
Not applicable. No adjudication method is mentioned, as this is non-clinical mechanical testing.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
Not applicable. This is not an AI/CADe device, and no MRMC study was conducted.
6. Standalone Performance Study
The "Performance Data" section describes standalone non-clinical testing of the device's mechanical properties and safety (pyrogenicity/endotoxin). These tests are conducted on the device itself (or its components) without human intervention to assess its intrinsic performance against engineering standards. The phrase "standalone" as used in AI performance studies (algorithm only) doesn't directly apply here, but the tests are focused solely on the device's characteristics.
7. Type of Ground Truth Used
Not applicable. For mechanical tests, the "ground truth" is typically defined by the test standard itself (e.g., specific load cycles, deformation limits, material properties).
8. Sample Size for Training Set
Not applicable. This is not an AI/CADe device; therefore, no training set was used.
9. How Ground Truth for Training Set Was Established
Not applicable. This is not an AI/CADe device; therefore, no training set ground truth was established.
§ 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.