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.
Open preview (PDF)Orthopaedic instruments — Drive connections — Part 2: Screwdrivers for single slot head screws, screws with cruciate slot and cross-recessed head screws
