Several authors mentioned that the improved cementing techniques clearly have not been shown to lead to improved long term stability of acetabular component on the contrary to the result of femoral component.
This has prompted changes in cup design and the use of uncemented acetabular component.
Since October, 1985 We have used hemispheral porous coated acetabular components and we have studied 87 patients with 93 cases to analize the incidence of clinical and radiographic signs of implant instability, and to determined
correation
between component loosening and osteoporosis, age and weight.
And we also tried to show the result with one of our cases in which moselized bone chip graft was performed into the screw holes of acetabular components at initial operation and to show one cases with severe groin pain which were revised.
@ES The results was as following:
@EN 1) Incidence of symptoms of acetabular instability, which were 9 cases(9.6%), were about twice as compared with that of radiographic instability, which were 4 cases (4.3%).
2) Of 4 cases with definitely unstable, 3 cases were reclassified as stable after two or three years with no evidence of additional migration and no symptoms. Only one case revealed continuous migration.
3) The hemispherical porous coated acetabular components appeared to become more stable with time even in the cases with technical errors, either beause of their shape or their surface characteristics.
4) There could be no correlation between acetabular component loosening and contact fit, angle of inclination, number of screws used for fixation, bone quality, age, and weight.
5) Groin pain could not always represent acetabular instability.
6) Reaming to sacrifice subchondral plate should be avoided to prevent migration.
7) Moselized bone grat which was derived from acetabular reaming into the screw holes might be one of the good methods to promote bone ingrowth.
8) In few cases of author's experience with revision, bone ingrowth around the porous surface of acetabular component could be well developed.
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