Abstracts Posters SICOT-SOF meeting Gothenburg 2010 _2_

Poster
Topic: Arthroplasty - Hip
Abstract number: 25302
POLYETHYLENE WEAR IN CEMENTLESS THA WITH 22MM ZIRCONIA HEAD -
COMPARISON WITH CROSS-LINKED POLYETHYLENE AND NON-CROSS-
LINKED POLYETHYLENE-
Tomofumi KOIZUMI, Takashi NISHIOKA, Tadashi MITSUHASHI, Takuya MISHIRO,
Yoichiro TAKATA
Takamatsu Redcross Hospital, Kagawa (JAPAN)
Purpose: The purpose of this study was to evaluate annual wear of cementless total
hip arthroplasty (THA) composed of a 22mm ziruconia head with cross-linked
polyethylene and conventional polyethylene liners retrospectively. Materials and
Methods: We studied 38 THAs with non-cross-linked PE (N) and 37 THAs with crosslinked
PE (C). The average age at surgery were 57.8 (N) and 61.2 years (C). The
average BMI was 23.2(N) and 23.0(C). Anteroposterior radiographs were used to
calculate annual linear and volumetric wear ratio as reported previously. The
average follow-up period was at least 5 years. Clinical outcomes were assessed by
Japan orthopaedic association (JOA) score.Results JOA score were recovered from
46.7 to 81.7 (N) and from 45.0 to 82.3 (C). In the N group, linear wear was gradually
increased from 0.26 to 1.0 mm and volumetric wear was increased from 77.1 to 333
mm3 collectively. There were not significant amount of linear and volumetric wear
detected after the first postoperative year in the C group. Total wear rate were
0.12mm/y, 40.7 mm3/y in C group and 0.01 mm/y, 2.5 mm3/y in N group.
Conclusion: The results showed that radiographic measurements of polyethylene
wear in cross-linked polyethylene were significantly less than that of conventional PE.
Cross-linked PE can lead to reduction and stabilization of free radicals in
polyethylene so that THA could be indicated for younger and more demanding
population.
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