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Class II Non-Spinal Metallic Bone Screws and Washers - Safety and Performance Based Pathway

This guidance covers Class II non-spinal metallic bone screws and washers intended for orthopedic fracture fixation, osteotomy, or small joint fusion/arthrodesis. It specifically applies to devices made from specific metallic materials (titanium alloys, stainless steel, cobalt-chromium alloys) and excludes mandibular, maxillofacial, cranial, orbital, and spinal applications, as well as devices with complex geometries or unique technological characteristics.

  1. Determine if device falls within scope of guidance
  2. Select appropriate material conforming to specified ASTM standards
  3. Conduct mechanical testing (torsional strength, driving torque, axial pullout)
  4. Perform biocompatibility evaluation or provide rationale for waiver
  5. Complete sterilization/reprocessing validation as applicable
  6. Prepare documentation demonstrating conformance to performance criteria
  7. Consider Pre-Submission if additional testing beyond guidance is needed
  8. Submit 510(k) using Safety and Performance Based Pathway with required test results and documentation

Key Considerations

Non-clinical testing

  • Mechanical bench testing required:
    • Torsional strength testing per ASTM F543
    • Driving torque testing per ASTM F543
    • Axial pullout strength evaluation through engineering analysis
  • Specific performance criteria provided for different screw diameters
  • Minimum of 5 samples required for testing

Biocompatibility

  • Evaluation required for implanted devices with prolonged/permanent contact
  • Testing endpoints include cytotoxicity, sensitization, irritation, systemic toxicity, pyrogenicity, genotoxicity, implantation, chronic toxicity, and carcinogenicity
  • Testing may be waived if using identical materials and processes as predicate device

Safety

  • Sterilization validation required for sterile devices
  • Reprocessing validation required for end-user sterilized devices
  • Must demonstrate sterility assurance level of 10-6

Other considerations

  • ASTM F543: Standard Specification and Test Methods for Metallic Medical Bone Screws
  • ISO 17665: Sterilization of health care products – Moist heat
  • ISO 11135: Sterilization of health care products – Ethylene oxide
  • ISO 11137-1/2/3/4: Sterilization of health care products - Radiation
  • ISO 11607-1/2: Packaging for terminally sterilized medical devices
  • ISO 10993-1: Biological evaluation of medical devices
  • ASTM F136: Standard Specification for Wrought Titanium-6Aluminum-4Vanadium ELI Alloy
  • ASTM F1472: Standard Specification for Wrought Titanium-6Aluminum-4Vanadium Alloy
  • ASTM F138: Standard Specification for Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless Steel

Original guidance

  • Class II Non-Spinal Metallic Bone Screws and Washers - Safety and Performance Based Pathway
  • HTML / PDF
  • Issue date: 2024-11-22
  • Last changed date: 2024-11-21
  • Status: FINAL
  • Official FDA topics: Medical Devices, 510(k), Orthopedic, Premarket
  • ReguVirta summary file ID: 6f5126f721b7ba26bae4415a57c26956
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