YY/T 0809.13-2020 in English

Standard Background and Scope of Application

This standard is modified to adopt the ISO 7206-13:2016 international standard, and establishes a test method for the anti-torsion performance of the head fixation of the stemmed femoral component in partial and total hip prostheses. It mainly solves the problem of loose connection between the femoral ball head and the cone in clinical practice, and is applicable to implant components made of metal/non-metal materials.

Core Test Principle

Through a static torque loading system, apply an increasing torque to the assembly at a rate of 20 N·cm/s±4 N·cm/s or 0.05°/s±0.01°/s until:
1) the peak value of the torque curve decreases
2) the limit value of 50 N·m is reached
3) an angular displacement of 20° occurs

Technical requirements for test equipment

A testing machine that complies with GB/T 16825.1 must be equipped with:

• Axial pressure loading accuracy ≤1%
• Torque measurement accuracy ≤1%
• Angular displacement monitoring tolerance ±0.5°

The cone unit must use the same material, process and size specifications as those used in clinical practice.

Specimen preparation specifications

6.3 Femoral head fixation method

Method 1: Processing parallel planes (diameter range 30%-70%)
Method 2: Epoxy resin bonding (covering ≥140° spherical surface)
Method 3: Casting resin embedding

Implementation recommendations

1. Before testing, the 5-DOF constraints of the fixture system must be verified (only axial rotation is restricted)
2. It is recommended to use a dynamic torque sensor to monitor the angle-torque curve in real time
3. After testing, clinical reuse of components is prohibited to avoid changes in material properties affecting secondary testing