[Significance of primary stabilization of the acetabular part of hip endoprosthesis in revision arthroplasty with extensive bone defects].

In this article author discuss medium term results of first or next secondary replacement of acetabular part of hip endoprosthesis--after filling up cavernous or segmental bone defects. There were analysed 104 operated hips 70 (67.3%) female and 34 (32.7%) male. Bilateral hip arthroplasty (in two sessions) was performed in 14 women and 5 men. The average age was 69.8 years. The mean time between the primary arthroplasty and the revision was 12.1 years. The follow up was 2-15 years, mean 5.4 years. Cemented acetabulum was used in 71 revisions (68.3%), self-threaded in 19 (18.3%) and pressed in 14 (13.5%). Destabilization and migration of acetabular part of prosthesis appeared in 14 events (13.5%). Radiolucency local zones on X-ray referred to possible pseudomembrane round the acetabular part without clinical manifestations were shown in 19 cases (18.3%). The study demonstrated that migration of acetabular part of hip prosthesis due to secondary stabilisation deficiency took place in hips were proper primary stabilisation was not achieved because of extensive bone defects.