Adequate femoral stem position and circumferential cement mantle are important factor preventing mechanical loosening of the femoral component. In an attempt to improve and facilitate the positioning of the femoral component, Zimmer Centralign
Precoat
femoral stem with attachment of a few small wings on the proximal and distal part of the stem was developed.
To investigate the effect of Zimmer centralizing femoral stem, we studied two series of the patients with Zimmer Precoat femoral stem and Zimmer Centralign femoral stem.
We assessed the stem position and cement mantle thickness on postoperative radiographs of 44 cases(36 Pts.) Zimmer Precoat femoral stem without centralizing device and 44(42 Pts.) Zimmer Centralign femoral stem, which were performed from
December,
1990
to December, 1994 by one surgeon at Guro hospital, Korea University.
29 hips(65.9%) of neutral, 10(22.7%) of mild valgus, 1(2.3%) of mild varus, 3(6.8%) of valgus and 1 of varus position in group I and 20(45.3%) of neutral, 16(36.4%) of mild valgus, 2(4.6%) of mild varus, 3(6.8%) of valgus and 3 of varus position
in
group ? were observed.
In cases of 3mm to 6mm cement mantle thickness in each 1,3,5,7 zone, 24 hips(54.5%), 24(54.5%), 13(29.5%) and 24(54.5$) in group I, 27(61.4%), 24(54.5%), 18(40.9%) and 31(70.5%) in group ? in A-P radiography and there were no significant
difference
in
each group(p>0.5), but the number of less than 2mm cement mantle thickness of group ? were significantly smaller than group I in zone 1,5,7 in A-P radiography and zone 1,5 in lateral radiography(p<0.01, 0.05).
Our results could suggest that there were somethat benefit of the Zimmer Centralign femoral stem regarding to the cement mantle thickness but not the stem position in the proximal femur and the centralizing wing of the femoral stem seem to be
more
extended in width for the centralizing effect, also care should be taken when inserting the femoral stem even though Zimmer Centralign stem.
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