Fig. 1. Close-up of test station no. 2 of HUT-4 hip joint simulator showing 50 mm
diameter Metasul MoM hip installed, without lubricant chamber. Gait of right hip is
simulated. Durom acetabular cup is cemented to a position of 70° inclination (66°
abduction, 32° anteversion). At this moment, i.e., maximum extension (outer cradle)
and neutral abduction–adduction (inner cradle) of the femoral head, and
maximum load of the second (toe-off) load peak (vertical loading bar above the
joint), high friction almost dislocates the joint as the motion is momentarily purely
abduction of head. Hence, 70° proved to be close to the highest possible inclination
angle that could be run with.