Convened under the auspicious of esteemed endorsers - ISTA

*Email: jerome.tonetti@free.frIn prevention of hip dislocation femoral head diameter increased. Ceramic liner and metal-backacetabular cup thicknesses were reduced, to allow 36 mm ball diameter in a 50 mm metal-backexternal diameter. Thus, new risk of ceramic liner breakage appears [1]. When Metal-backundergoes deformation during impaction [2], ceramic liner might be mal seated. Contacts reduceto some stress riser points instead of large surface could lead to ceramic breakage [3]. The intraoperative procedure to get and check a perfect insertion could be time consuming. Impingementbetween metal stem neck and ceramic liner edge is a cause of metal wear and ceramic chippingbreakage [1]. We propose (1) a ceramic liner pre assembled in the metal-back to avoid falseceramic on metal strain spread and (2) metal rim to prevent stem on ceramic liner impingementwith a conical range of motion up to 134°.Out of 2500 implantations, we did a prospective survey of 100 pre assembled ceramic liners.We review the patients at 2 years follow-up. Functional results were excellent in 92 patients,good in 6 patients, fair in 2 patients. Five patients complained about groin pain after strongactivities, related to ilio psoas muscle conflict. Two patients reported a transient squeaking. Wefound neither ceramic liner breakage nor hip dislocation. No patient underwent revisionarthroplasty.Our results are encouraging. This implant design is secure with a quick and simple implantationtechnique. Results should be confirmed by further follow-up in a larger population.[1] Hwang SK, Oh JR, Her MS, Shim YJ, Cho TY, Kwon SM. Fracture-dissociation ofCeramic Liner. Orthopedics. 2008 Aug; 31, 8: 804.[2] Lin ZM, Meakins S, Morlock MM, Parsons P, Hardaker C, Flett M, Isaac G.Deformation of press-fitted metallic resurfacing cups. Part 1: Experimental simulation. Proc InstMech Eng H. 2006, 220; 2: 299-309[3] Miller AN, Su EP, Bostrom MP, Nestor BJ, Padgett DE. Incidence of Ceramic LinerMalseating in Trident Acetabular Shell. Clin Orthop Relat Res. 2009, 467; 6: 1552-6.Poster: 112Conversion of Arthrodesis to Arthroplasty in Hip Joint*Takuma Yagura - Kansai Medical University - Osaka, JapanHirokazu Iida - Kansai Medical University - Hirakata, JapanTakahiko Wada - Kansai Medical University - Hirakata, JapanNaofumi Okamoto - Kansai Medical University - Hirakata, JapanTomohisa Nakamura - Kansai Medical University - Hirakata, Japan*Email: takuma.620@hotmail.co.jpBackground: Conversion of arthrodesis to arthroplasty in hip joint remains controversial. Itsdifficulties include in not only the operative techniques, but also the postoperative slowfile:///E|/ISTA2010-Abstracts.htm[12/7/2011 3:15:47 PM]