Overview
ISO 8827:1988 specifies general requirements for implants for surgery - staples with parallel legs for orthopaedic use. The standard defines dimensions, tolerances, shapes and designation conventions for parallel‑leg staples, illustrates typical forms, and includes an informative annex with guidance on selection and clinical use. It is intended for manufacturers, regulatory bodies, quality engineers and clinicians involved with orthopaedic staples.
Key topics and technical requirements
- Dimensions & designation: Staples are designated by overall length (l), overall width (b) and diameter (d) in millimetres (e.g., 25 x 20 x 1). For unequal leg lengths, each leg length must be specified.
- Tolerances and geometry:
- Overall length and width: nominal ±1 mm.
- Parallelism: axis of each leg must lie within a cylindrical tolerance zone of 0.5 mm diameter.
- Curvature: internal radius of curvature for wire staples must be at least 2 mm or the wire diameter, whichever is greater; curvature must have a smooth contour.
- Tips: conical, trocart (trocar), lance or flattened (e.g., tapered in a plane).
- Materials and mechanical properties:
- Acceptable materials include austenitic stainless steel wire (per ISO 5332-1), cobalt-chrome casting/alloy types (per ISO 5832 series), and titanium forging alloys (per ISO 5832‑? references in the standard).
- Minimum mechanical values are specified for different materials and wire diameters (e.g., stainless wire tensile strength and yield, cobalt‑chrome and titanium tensile/elongation ranges). Tests are referenced to ISO 6892 (tensile testing).
- Surface finish: Surfaces must be free from burrs, scratches and visible defects; options such as ribs, spikes or coatings are allowed but must not weaken legs.
- Marking and packaging: Must comply with ISO 6018 requirements for labelling, packaging and practice.
- Informative annex: Guidance on staple selection and use (not normative) - e.g., use larger cross-sections, ribs or stronger alloys to reduce breakage; orientation and placement considerations for epiphyseal retention; surface features to improve fixation.
Applications and users
- Who uses the standard: orthopaedic implant manufacturers, design engineers, surgical instrument suppliers, hospital procurement, regulatory authorities and standards committees.
- Practical applications: design specification and quality control of orthopaedic staples used for bone fixation, epiphyseal retention and soft tissue anchoring; procurement specifications and conformity assessments for surgical staples.
Related standards
- ISO 5332-1 (surgical implant stainless steel wire)
- ISO 5832-3 / -4 / -5 (implant alloys: cobalt‑chrome, cobalt‑chrome‑molybdenum, etc.)
- ISO 6892 (metal tensile testing)
- ISO 6018 (marking, packaging and housekeeping for surgical implants)
Keywords: ISO 8827, orthopaedic staples, implants for surgery, parallel‑leg staples, dimensions and tolerances, surgical implant materials, staple selection guidance.