This study compared the primary stability of two commercially
available acetabular components from the same manufacturer, which
differ only in geometry; a hemispherical and a peripherally enhanced
design (peripheral self-locking (PSL)). The objective was to determine
whether altered geometry resulted in better primary stability. Acetabular components were seated with 0.8 mm to 2 mm interference
fits in reamed polyethylene bone substrate of two different densities
(0.22 g/cm3 and 0.45 g/cm3). The primary stability
of each component design was investigated by measuring the peak
failure load during uniaxial pull-out and tangential lever-out tests.Objective
Methods
We report the use of a 15° face-changing cementless
acetabular component in patients undergoing total hip replacement
for osteoarthritis secondary to developmental dysplasia of the hip.
The rationale behind its design and the surgical technique used
for its implantation are described. It is distinctly different from
a standard cementless hemispherical component as it is designed
to position the bearing surface at the optimal angle of inclination,
that is, <
45°, while maximising the cover of the component by
host bone.
