YY/T 1426.1-2016Implants for surgery - Wear of total knee-joint prostheses - Part 1: Loading and displacement parameters for wear-testing machines with load control and corresponding environmental conditions for test (English PDF)

3.1 Before and after displacement APdisplacement

The offset of the axial force axis relative to the buckling/extension axis measured in the direction perpendicular to the axial force axis and the buckling/extension axis.

Note 1. A is the abbreviation of "anterior"; P is the abbreviation of "posterior".

Note 2. When the total knee joint is at the reference position (3.7), the displacement is set to zero, and when the axial force axis is relative to the reference position of the total knee joint

Defined as a positive value (3.7), see Figure 1.

3.2 Before and after force APforce

Perpendicular to the tibial axis and the flexion/extension axis, the force acting on the tibial plateau component, the force acting through the axial force axis.

Note. When the direction of action of the force along the tibial component from the forward, the definition is positive, see Figure 1.

3.3 Axial force axisforce

The force applied to the tibial component of the knee prosthesis parallel to the tibial axis.

Note. When the direction of force from the bottom up when the provisions of the force is positive (see Figure 1 and Figure 2).

3.4 Axial force axis

Axial force of the line, the line through the knee prosthesis tibial component from the tibial axis to the tibial lateral displacement of 0.07w ±

0.01 w, where w is the total width of the tibial component, see ISO 7207-1.

Note 1. See Figure 2.

Note 2. For an average width (i.e., 74 mm) tibial component, the 0.07 w value is approximately equal to 5 mm.