The results of fifty-five consecutive primary total hip arthroplasties in which a Harris-Galante porous coated acetabular component had been used were reviewed after a minimum of five years.
Areas of gaps between the porous mesh at the periphery of the acetabular component and the bone were seen on the immediate postoperative radiographs of twenty-eight hips(50.9%).
At the second year follow up, a radiolucent line was found in twenty-six hips(47.3%).
These radiolucent lines were never wider than one milimeter and were most frequently located in zone III.
At the time of last follow-up evaluation, a progressive radiolucent line was identified around eight hips and a discontinous radiolucent lien was present in all three zones around eleven.
The continous radiolucent line was identified in two hips.
Aprogressive radiolucent line developed around only two of twenty-seven hips that were not associated with an initial peripheral gap, but a progressive radiolucent line developed aroune six of the twenty-eight hips that were associated with such
a
gap.
An initial peripheral gap will subsequently show a progressive radiolucent line. None of the acetabular components were loose, however, six acetabular component were revised due to dissociation of polyethylene liner, postoperative femoral
fractures
and
revision of femoral stem in two hips each.
In six cases of the author's experience with revision, bone ingrowth around the porous suraface of acetabular components was well developed.
Our experience with Harris-Galante porous coated acetabular components suggests that the technique used for implantation may be important not only for initial fixation and ingrwoth of bone, but also, more importantly, for the design of the
liner-metal
back locking mechanisms.
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