Technical Considerations for Non-Spinal Metallic and Polymer Bone Plates and Screws
This guidance document covers class II, orthopedic, non-resorbable, non-spinal bone plate and screw systems, stand-alone bone screws, and associated washers regulated under 21 CFR 888.3030 and 21 CFR 888.3040. It specifically addresses devices made from common metallic materials (titanium alloys, stainless steel, cobalt-chrome) and polymers (PEEK, CFR PEEK). The guidance excludes devices for spinal, mandibular, maxillofacial, cranial and orbital applications, as well as devices with unique characteristics like nitinol materials, coatings, antimicrobial agents, or additive manufacturing.
Recommended Actions
- Determine worst-case device configurations for testing based on dimensions and design features
- Conduct required mechanical testing:
- Plate bending tests
- Screw insertion/removal torque
- Screw torsional strength
- Screw pullout strength
- Complete biocompatibility evaluation for all patient-contacting materials
- Validate sterilization process if provided sterile
- Validate reprocessing instructions if reusable
- Develop comprehensive labeling including all required elements
- Evaluate and document MR compatibility
- Validate packaging and shelf life if provided sterile
- Consider submitting a Pre-Submission to FDA for feedback if device has unique characteristics not covered by guidance
- Prepare 510(k) submission including all test reports, validations, and required documentation
Key Considerations
Clinical testing
- Generally unnecessary for most bone plates and screws
- May be required for:
- Indications dissimilar from legally marketed devices
- New technology different from legally marketed devices
- Cases where engineering/animal testing raises issues needing clinical evaluation
Non-clinical testing
- Mechanical performance testing required for plates:
- Single cycle bend testing per ASTM F382
- Fatigue testing may be needed for devices with different technological features
- Mechanical performance testing required for screws:
- Insertion/removal torque testing per ASTM F543
- Torsional strength testing per ASTM F543
- Pullout strength testing per ASTM F543
Labeling
- Must include:
- Device description (material, sterility status)
- Device use (single-use/reusable, intended users/populations)
- Contraindications
- Warnings
- MR safety information
- Cleaning/sterilization instructions if applicable
- Removal instructions when appropriate
Biocompatibility
Must address following endpoints for implants:
- Cytotoxicity
- Sensitization
- Irritation/intracutaneous reactivity
- Acute systemic toxicity
- Material mediated pyrogenicity
- Subacute/subchronic toxicity
- Genotoxicity
- Implantation
- Chronic toxicity
- Carcinogenicity
Safety
- Must address MR safety and compatibility
- Must address pyrogenicity for sterile devices
- Must validate shelf life and packaging integrity
Other considerations
- Sterilization validation required for sterile devices
- Reprocessing validation required for reusable instruments
- Engineering analysis can be used in lieu of some mechanical testing with proper justification
Relevant Guidances
- Use of ISO 10993-1 for Biological Evaluation and Testing of Medical Devices
- Testing and Labeling of Medical Devices for Magnetic Resonance (MR) Environment Safety and Compatibility
- Reprocessing Instructions for Reusable Medical Devices and Non-Sterile Single-Use Devices - Development and Validation
- Submission Requirements for Terminally Sterilized Medical Devices
- Requests for Feedback and Meetings for Medical Device Submissions: The Q-Submission Program
Related references and norms
- ASTM F382: Standard Specification and Test Method for Metallic Bone Plates
- ASTM F543: Standard Specification and Test Methods for Metallic Medical Bone Screws
- ASTM F1839: Standard Specification for Rigid Polyurethane Foam for Use as a Standard Material for Testing Orthopaedic Devices and Instruments
- ISO 11607-1: Packaging for terminally sterilized medical devices – Part 1: Requirements for materials, sterile barrier systems and packaging systems
- ISO 11607-2: Packaging for terminally sterilized medical devices – Part 2: Validation requirements for forming, sealing and assembly processes
- ASTM F1980: Standard Guide for Accelerated Aging of Sterile Barrier Systems for Medical Devices
Original guidance
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