We previously reported the seven-year results of the use of a
hemispherical, porous-coated acetabular component in twenty consecutive
primary total hip arthroplasties in a highly selected group, namely, patients
with severe developmental dysplasia or total dislocation of the hip. The
present report describes the outcomes of those hips nine years later, at an
average follow-up of sixteen years (range, 11.5 to nineteen years). Since the
time of our prior report, two shells were revised; one revision was done
because of aseptic loosening and the other, because of polyethylene liner
dissociation without tine fracture. The remaining shells were well fixed. No
pelvic osteolysis was evident on plain radiographs. The average polyethylene
liner wear rate was 0.09 mm/yr. With failure defined as aseptic loosening of
the shell, the average sixteen-year survival for the shell was 92%. We believe
that this cup had excellent fixation at a long duration of follow-up of
sixteen years in this highly selected set of patients with difficult hip
problems.
Level of Evidence: Therapeutic Level IV. See Instructions
to Authors for a complete description of levels of evidence.