ISO 8319-2:1986

Overview

ISO 8319-2:1986 specifies requirements for screwdrivers used in orthopaedic surgery to insert and remove bone screws with single-slot heads, cruciate slots and cross-recessed (modified Phillips) heads. The standard focuses on drive connections and screwdriver bits - defining shapes, dimensions, materials, mechanical performance and marking - while avoiding undue restrictions on design. Screwdrivers covered are intended for use with bone screws that conform to ISO 9268.

Key topics and technical requirements

• Design and dimensions
  • Defines bit geometries for hand and power-driven screwdrivers for single-slot, cruciate and cross-recessed heads.
  • Includes dimension tables and figures for bit shapes, flutes and recess profiles (see Table 1 and figures in the standard).
• Materials and hardness
  • Blade materials specified include martensitic stainless steel (e.g., grades from ISO 683/13) and cold-worked cobalt‑chromium‑tungsten‑nickel alloys (ISO 5832/5).
  • Rockwell hardness ranges are given (e.g., stainless steel ~48–54 HRC; cobalt‑chromium alloys ~48–50 HRC).
• Mechanical performance and testing
  • Torque and torsion testing procedures for blades, bits and complete screwdrivers are defined (including use of torque-testing dies).
  • The blade-to-handle connection must withstand specified test torques without loosening, fracture or permanent deformation (the text includes a test torque example of 9.7 N·m).
  • Slot/drive test discs and dimensional tolerances are specified in relation to ISO 2380 and related test methods.
• Marking
  • Required permanent markings include intended screw size (code and thread diameter per ISO 9263), manufacturer name/trademark, ISO 8319 part number (if space) and material (if space).

Applications and users

• Who uses ISO 8319-2
  • Medical device manufacturers that design and produce orthopaedic screwdrivers and driving tools.
  • Surgical instrument designers and quality engineers responsible for acceptance testing and compliance.
  • Hospitals, procurement and sterile services teams specifying compliant instruments for orthopaedic procedures.
  • Test laboratories that validate mechanical and material properties of surgical screwdrivers.
• Practical value
  • Ensures interchangeability and reliable engagement between drive tools and bone screws.
  • Reduces risk of tool failure during surgery by specifying materials, hardness and torque resistance.
  • Supports regulatory compliance and consistent manufacturing quality.

Related standards

• ISO 9268 (metal bone screws - dimensions)
• ISO 2380 (screwdriver blades for slotted head screws)
• ISO 683/13 (heat-treated and wrought stainless steels)
• ISO 5832/5 (wrought cobalt‑chromium‑tungsten‑nickel alloy)
• ISO 6508 / ISO 6568 (hardness and test methods)
• ISO 9263 (screw size coding and marking)

Keywords: ISO 8319-2, orthopaedic instruments, drive connections, screwdrivers, bone screws, single-slot, cruciate, cross-recessed, surgical instruments, torque test, medical device standards.