Non-Clinical Testing and Labeling Requirements for Femoral Stem Prostheses in Hip Replacement Systems
This guidance addresses the development of non-clinical information, testing, and labeling of femoral stem prostheses for both class II and class III devices intended as components for cemented or uncemented hip replacement systems. It covers the femoral neck, shaft, and head but does not address the interaction between femoral heads and acetabular components.
What You Need to Know? 👇
What are the key fatigue testing requirements for femoral stem prostheses according to FDA guidance?
FDA recommends stem fatigue testing using ASTM F1612-95 (with torsion) or F1440-92 (without torsion) standards, testing six devices for 5 million cycles. Worst-case designs should be tested with proper potting levels and acceptance criteria from ISO 7206-8:1995 or ASTM F2068-03.
When is clinical data required for femoral stem prostheses submissions?
Clinical evaluation may be necessary for new or significantly different femoral stem materials or designs beyond bench testing. FDA considers these devices significant risk requiring IDE approval. Contact the Orthopedic Joint Devices Branch before IDE submission to discuss study design.
What biocompatibility testing is needed for femoral stem prostheses?
Follow ISO-10993 guidance for permanent implanted devices with tissue/bone contact. If materials are identical to predicate devices with same contact type/duration, reference the predicate. Otherwise, evaluate per ASTM F748 and/or ISO 10993-1 if materials don’t conform to FDA-recognized standards.
How should modular connections in femoral stems be evaluated?
Perform modular connection, fretting, and corrosion testing per FDA’s “Guidance Document for Testing Non-Articulating, ‘Mechanically Locked,’ Modular Implant Components.” Include assembly/disassembly information and details of all modular connections in device description. Provide rationale if testing deemed unnecessary.
What special considerations apply to novel stem materials like polymers or composites?
Standard ASTM/ISO fatigue tests may be inappropriate for polymer/composite stems failing below standard criteria due to new mechanisms (delamination, creep, shear failure). Alternative testing methods require clinical evidence, stress analyses, and mechanical testing justifying load configurations and test models.
What device description information must be included in femoral stem submissions?
Provide component names/part numbers, geometry descriptions, dimensional ranges, photographs, engineering drawings, surface roughness (Ra), material composition, manufacturing processes, coating characterization, modular connection details, and unique surgical instrumentation descriptions. Include applicable classification regulations and product codes.
What You Need to Do 👇
Recommended Actions
- Determine if device requires clinical evaluation based on novelty of materials/design
- Plan and execute required non-clinical testing program:
- Fatigue testing of stem and neck
- Biocompatibility testing
- Sterilization validation
- Modular connections testing if applicable
- Prepare detailed device description documentation
- Develop comprehensive labeling meeting requirements
- Compile complete test reports with all required elements
- Consider worst-case scenarios for all testing
- Validate any FEA models with experimental data
- Ensure compliance with applicable standards
- Prepare IDE application if clinical study needed
- Contact FDA Orthopedic Joint Devices Branch for guidance if needed
Key Considerations
Clinical testing
- Clinical evaluation may be necessary for new or significantly different femoral stem materials or designs
- Clinical studies must be conducted under IDE regulations if performed in the US
- Device is considered a significant risk device
Non-clinical testing
- Fatigue testing required for femoral stem and neck
- Test methods should follow ASTM F1612-95, ASTM F1440-92, or ISO 7206-4:2002 standards
- Test worst-case designs
- Minimum 6 samples tested for 5 million cycles for stem and 10 million cycles for neck
- Additional testing may be needed for novel materials/designs
Labeling
- Must include clear instructions for use
- Should describe intended use, indications, and fixation method
- Should identify factors influencing device performance
- Should list known adverse events
- Must comply with 21 CFR 801 requirements
Biocompatibility
- Testing required per ISO 10993-1 for tissue/bone contacting permanent implants
- Can reference predicate device if identical materials used
- Follow ASTM F748 and/or ISO 10993-1 for new materials
Safety
- Sterility assurance level (SAL) of at least 1 x 10-6 required
- Sterilization cycle must be validated per 21 CFR Part 820
Other considerations
- Detailed device description required including dimensions, materials, surface characteristics
- Modular connections, fretting and corrosion testing recommended
- Complete test reports required with specified elements
Relevant Guidances 🔗
- Use of ISO 10993-1 for Biological Evaluation and Testing of Medical Devices
- Design Controls for Medical Device Manufacturers
- Recommended Format and Content for Non-Clinical Bench Performance Testing in Medical Device Premarket Submissions
- Testing Requirements for Orthopedic Implants with Modified Metallic Bone-Interface Surfaces
- Testing of Non-Articulating, Mechanically Locked Modular Implant Components in Orthopedic Devices
Related references and norms 📂
- ASTM F1612-95: Standard Practice for Cyclic Fatigue Testing of Metallic Stemmed Hip Arthroplasty Femoral Components with Torsion
- ASTM F1440-92: Standard Practice for Cyclic Fatigue Testing of Metallic Stemmed Hip Arthroplasty Femoral Components without Torsion
- ISO 7206-4:2002: Implants for surgery - Determination of endurance properties of stemmed femoral components
- ISO 10993-1: Biological evaluation of medical devices
- ASTM F748: Standard Practice for Selecting Generic Biological Test Methods for Materials and Devices