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*Naoyuki Katayama - Hokkaido Orthopaedic Memorial Hospital - Sapporo, JapanHisanori Oura - Hokkaido Orthopaedic Memorial Hospital - Sapporo, JapanShigeo Matsuno - Hokkaido Orthopaedic Memorial Hospital - Sapporo, Japan*Email: Hip-katayama@jcom.home.ne.jpAbstract: We retrospectively reviewed 495 patients (572 hips) who had undergone primarytotal hip arthroplasty(563 hybrid THAs, 9 cemented THAs ) between April 2001 and December2007 using a collarless polished double tapered femoral component (Exeter universal stem)after two to nine years (mean 4.0). Preoperative diagnosis was osteoarthritis in 482(84%),avascular necrosis in 48(8.4%), rheumatoid arthritis in 22(3.8%), fracture in 16(2.8%),ankylosing spondylitis in three(0.5%), PVS in one(0.17%). There were 491 women and 81 menwith a mean age at operation of 60.8 years (23 to 88). All stems were implanted by onesurgeon(N.K.) with so-called second-generation cementing technique. We used Simplexcement with a distal cement restrictor(Exeter plug; Stryker Howmedica), pulsatile lavage,retrograde cementing with a gun and proximal pressurization. We did not use vacuum-mixing,or centrifugation. The sizes of femoral stems used were 33.0 mm offset in four, 35.5 mm in 122,37.5 mm in 404, 44.0 mm in 41, 50.0 mm in one.Radiological analysis was performed on calibrated plain radiographs taken in two planes.All stems were inserted within 4° of neutral alignment in the AP plane. Three stems were inmore than 3° of varus, and one was in more than 3° of valgus. Cementing grades(Barrack)were A in 59.1 %, B in 36.6 %, C in 0.5%. All the stems subsided at the stem-cement interfacevertically. The mean total subsidence was 0.77mm (0.14 to 2.17). 55 hips(9.6%) showedpostoperative cortical hypertrophy: 48 in zone 5, 12 in zone 6, and nine in zone 3. Only onehip had ectopic ossification(Brooker grade 3). There was no radiolucent line in all hips. Onepatient showed focal osteolysis in zone 6 . In 38 of the hips (6.6 %) intramedullary cementleakage or plug migration were found.There have been no revisions for aseptic stem loosening. Six stems required re-operation: fivefor infection, and one for recurrent dislocation. Other three hips required re-operation forrecurrent dislocation , and one for cup loosening(all stems still survived). Survival for the stemswith an endpoint of revision for aseptic loosening was 100%. Survival for the stems with anendpoint of revision for any reason was 98%. This study confirms that Exeter universal stemssubside within the cement mantle but without loosening. However, occasionally Exeteruniversal stem is too long for a small Japanese patient, so that we need a shorter stem withlarger offset.Poster: 43Total Hip Arthroplasty With a Custom-Made Stem Using CT BasedNavigation System*Kenji Kawate - Nara Medical University - Kashihara, JapanIkuo Kawahara - Nara Medical University - Kashihara, JapanTomoyuki Ueha - Nara Medical University - Kashihara, Japanfile:///E|/ISTA2010-Abstracts.htm[12/7/2011 3:15:47 PM]