Background: During revision total hip arthroplasty, the acetabular
component is often secured with screws to ensure initial press-fit stability.
The purpose of the present study was to assess a series of acetabular
revisions involving the use of a porous-coated acetabular component that was
stabilized with peripheral screws and to evaluate the results in relation to
the acetabular bone deficiencies that were present at the time of the revision
Methods: From 1987 to 1991, 203 consecutive acetabular revisions
were performed. In 142 hips, a severe acetabular bone deficiency that did not
require an allograft was reconstructed with a porous-coated acetabular cup
that was secured with a minimum of two peripheral screws. After an average
duration of follow-up of 13.2 years, 134 hips were reviewed clinically and
radiographically. The procedure was considered to be a clinical failure if the
component was revised or if the postoperative clinical scores were poorer than
the preoperative scores.
Results: At the time of the most recent follow-up, 127 (95%) of the
134 hips were stable and clinically successful. The other seven hips (5%) were
considered to have failed. Five of these seven hips failed because of an
infection, and two failed because of aseptic loosening. Five (19%) of the
twenty-seven hips with a Paprosky type-3A defect (a defect in which 30% to 50%
of the host acetabulum is missing) failed.
Conclusions: Revision total hip arthroplasty with use of a
porous-coated acetabular component that is fixed with peripheral screws can
provide long-term durability in hips with severe acetabular defects that do
not require the use of an allograft (Paprosky type-1 and type-2 defects). We
recommend that when an acetabular implant with peripheral screws is used for
the treatment of a more severe (type-3) defect, the cup should be augmented
with structural allograft to improve initial stability, or other implants
should be utilized.
Level of Evidence: Therapeutic Level IV. See Instructions
to Authors for a complete description of levels of evidence.