Suture anchors (bone anchors) are medical devices used in orthopaedic surgery to attach soft tissue (like tendons and ligaments) to bone. These devices are commonly employed in procedures involving the shoulder, knee, hip, and other joints to repair torn ligaments and tendons.

Design and Materials:

• Suture anchors can be made from various materials, including metal (titanium), polymers (like PEEK), and biodegradable materials (like polylactic acid).
• They come in different shapes and sizes, with designs that include screws, barbs, and hooks to ensure secure fixation in the bone.

Functionality:

• The anchor is inserted into a pre-drilled hole in the bone, and sutures attached to the anchor are used to secure the soft tissue.
• Once in place, the anchor holds the tissue firmly against the bone, allowing it to heal in the correct position.

Types of Suture Anchors:

• Bioabsorbable Anchors: Made from materials that gradually dissolve in the body, eliminating the need for removal surgery.
• Non-absorbable Anchors: Made from materials like metal or non-degradable polymers, these remain in the body permanently.

Note: Please note that suture anchor devices may have historically been cleared with other product codes (e.g., HWC); however, these product codes are more appropriate for other orthopaedic devices (e.g., fixation screws). To ensure that the product code reflects the intended device type (i.e., bone anchor), we recommend that future submissions be submitted under the product codes MAI or MBI. For determination of substantial equivalence, predicate suture anchors cleared under other product codes may be used.

For reference:  https://www.fda.gov/media/72235/download

Bone anchor (suture anchor) devices used in the appendicular skeleton for attachment of soft tissue to bone. This attachment may be achieved by attaching one end of a suture to the soft tissue and the other end to a device that is inserted into the bone. 

General Suture Anchors

Dimensions and Material Composition

Dimensions:

• Length
• Inner Diameter: Specify the inner diameter if the anchor is hollow or has an internal channel.
• Outer Diameter:
• Drawings or Figures

Material Composition and Material Standards: Reference applicable material standards such as ASTM F136 for titanium, ISO 5834 for polyethylene.

Suture Details

• Identify the suture material and any coatings or additives.
• Provide the suture size according to the United States Pharmacopoeia (USP) system.
• If the suture has been previously cleared by the FDA, include the 510(k) number and confirm its identity or document any changes.

Suture/Anchor Attachment Mechanism: Explain how the suture is attached to the anchor (e.g., tied to an eyelet, preloaded on an inserter).

Anchors without Sutures: If the anchor system does not include a suture but is intended for use with a generic suture of a specific size, you should ensure that the recommended suture size (e.g., USP size 2) and type (i.e., absorbable vs. non-absorbable) is specified in the submission and the draft labelling.

System Components: Describe all components of the system (e.g., suture anchor driver, specific suture types) that are compatible with the anchor.

Bone Preparation: Detail the method for preparing the bone for anchor insertion, such as self-tapping or the recommended pilot hole dimensions

Conformance to Material Standards

• ASTM F2063: Standard Specification for Wrought Nickel-Titanium Shape Memory Alloys for Medical Devices and Surgical Implants and including the chemical composition and mechanical properties.

Chemical Composition and Mode of Action

• If no applicable standard exists, provide the chemical composition of the nitinol alloy.
• Describe whether the anchor relies on thermal shape memory or super elasticity.
• Explain how the anchor transitions to the specified size and shape, such as through heating or mechanical deformation.

Transition Temperatures

• Provide the austenite start (As) and finish (Af) temperatures of the final, finished device.
• Use samples from multiple production lots.
• Recommended methods include ASTM F2004 and ASTM F2082 or equivalent methods.

Specifications: Define the acceptable Af temperature range for the suture anchor to ensure it performs as intended within the body.

Final Processing and Surface Treatment: Detail the final processing steps, including surface treatments like shape setting, polishing, and passivation and Include information on any electro-polishing or passivation steps.

Material of Construction and Standards

• Provide the material for construction.
• If using a material identical to a predicate device, specify the 510(k) number for the predicate.

Analytical Properties

• Include properties such as molecular weight, residual monomer content, and crystallinity and Provide data supporting these properties.

Degradation Mechanism

• Describe the degradation mechanism, such as hydrolysis and detail how the material degrades in the body and over what time frame.

Degradation Profile

• Provide a detailed degradation profile, showing how the anchor breaks down over time and Include data from in vitro or in vivo studies that demonstrate the degradation behaviour.

In both Traditional and Abbreviated 510(k) submissions, the FDA advises including the listed section headings in the recommended sequence. Although certain sections may not apply to your device, maintaining the specified order of headings is suggested by the FDA to facilitate expedited reviews.

1. FDA Medical Device User Fee Cover Sheet
2. FDA Premarket Review Submission Cover Sheet
3. FDA 510(k) Cover Letter
4. FDA 510(k) Indications for Use Statement
5. FDA 510(k) Summary or FDA 510(k) Statement
6. FDA Truthful and Accuracy Statement
7. FDA Class III Summary and Certification
8. Financial Certification or Disclosure Statement
9. Declarations of FDA Conformity and Summary Reports
10. FDA 510 (k) Executive Summary
11. Medical Device Description
12. FDA 510(k) Substantial Equivalence Discussion
13. Proposed Labeling
14. Sterilization and Shelf Life
15. Biocompatibility
16. Software
17. Electromagnetic Compatibility and Electrical Safety
18. Performance Testing-Bench
19. Performance Testing-Animal
20. Performance Testing-Clinical

For bone anchors considered as implant devices in contact with tissue/bone for a permanent duration, the following endpoints should be addressed in your biocompatibility evaluation according to ISO 10993-1 and FDA guidance

• Cytotoxicity
• Sensitization
• Irritation or Intracutaneous Reactivity
• Acute Systemic Toxicity
• Material-Mediated Pyrogenicity
• Subchronic toxicity (Sub-acute toxicity)
• Genotoxicity (We recommend that both mutagenicity and clastogenicity be assessed.)
• Implantation
• Chronic Toxicity
• Carcinogenicity

For patient-contacting device-specific instrumentation (e.g., inserter shafts) in contact with tissue/bone for a temporary duration, the following endpoints should be addressed:

• Cytotoxicity
• Sensitization
• Irritation or Intracutaneous Reactivity
• Acute Systemic Toxicity
• Material-Mediated Pyrogenicity

1. Suture Characterization
2. Insertion Testing: ASTM F1839: Standard Specification for Rigid Polyurethane Foam for Use as a Standard Material for Testing Orthopedic Devices and Instruments.
3. Pullout Testing
4. Component Interconnection Testing
5. Fatigue Testing
6. Corrosion: ASTM F2129: Standard Test Method for Conducting Cyclic Potentiodynamic Polarization Measurements to Determine the Corrosion Susceptibility of Small Implant Devices.
7. Degradation Testing:

• ASTM F1635: Standard Test Method for in vitro Degradation Testing of Hydrolytically Degradable Polymer Resins and Fabricated Forms for Surgical Implants,
• ISO 13781: Implants for surgery — Homopolymers, copolymers and blends on poly(lactide) — In vitro degradation testing
• ASTM F2502: Standard Specification and Test Methods for Absorbable Plates and Screws for Internal Fixation Implants.

For devices labelled as sterile.

Based on the method we use the standards such as

• ISO 17665-1 Sterilization of health care products – Moist heat – Part 1: Requirements for the development, validation, and routine control of a sterilization process for medical devices
• ISO 11135-1 Sterilization of health care products – Ethylene oxide – Part 1: Requirements for development, validation, and routine control of a sterilization process for medical devices
• ISO 11137-1 Sterilization of health care products—Radiation—Part 1: Requirements for development, validation, and routine control of a sterilization process for medical devices.
• 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 process

Reprocessing: Many of the patient-contacting components of bone anchor instrumentation are reused, and should be adequately cleaned, disinfected, and sterilized between uses to minimize infections and prevent device degradation

• Shelf-life testing is conducted to support the proposed expiration date through valuation of the package integrity for maintaining device sterility and/or evaluation of any changes to device performance or functionality.
• ASTM F1980: Standard Guide for Accelerated Aging of Sterile Barrier Systems for Medical Devices

• ANSI/AAMI/ISO 11607-1: Packaging for terminally sterilized medical devices – Part 1: Requirements for materials, sterile barrier systems and packaging
• ANSI/AAMI/ISO 11607-2: Packaging for terminally sterilized medical devices – Part 2: Validation requirements for forming, sealing and assembly processes.

• The proposed labelling must include comprehensive details about the bone anchor, including its intended use and directions for use.
• Regulation: Must satisfy the requirements outlined in 21 CFR 807.87(e).

Clinical testing was not necessary for demonstrating substantial equivalence.

Necessity of Clinical Evidence:

• Clinical studies may be necessary in specific situations where non-clinical evaluations do not fully address clinical outcomes or risks.

Situations Requiring Clinical Testing:

• Different Indications for Use
• New Technology.
• Engineering/Animal Testing Issues.
• Lower Mechanical Properties