Convened under the auspicious of esteemed endorsers - ISTA

Poster: 52Development of a Constant Load Dynamic Gap Measurer for Soft TissueBalancing in Total Knee ArthroplastyDai-Soon Kwak - The Catholic University of Korea - Seoul, Korea*Yong In - Uijongbu St. Mary's Hospital - Uijongbu-Si, Korea, Republic ofSeung-Ho Han - The Catholic University of Korea - Seoul, Korea*Email: iy1000@catholic.ac.krFlexion-extension gap balancing is recognized as an essential part of total knee arthroplasty(TKA). Although several devices (spreader or tensor) for assessing flexion-extension gap havebeen described, these devices limit assessments to knees in full extension and in 90° flexiononly. Manual distraction force applied to the device can also vary by time or surgeon. Wedeveloped a new device for dynamic gap balancing which can offer constant load to the gapbetween femur and tibia using pneumatic pressure during range of motion. The purpose of thisstudy was to determine distraction force to apply and to evaluate reproducibility of the newdevice.Biomechanical tests were performed to evaluate the variations among experienced orthopaedicsurgeons in manual force for distracting the existing spreader. A spreader device (Aesculap,Tuttlingen, Germany) was mounted on Instron materials testing machine (Instron 5567, MA,USA). Three experienced surgeons distracted the spreader device using a clamp with manualmaximal force 5 times each. Reliability test for the new device was performed using 5 cadavericknees by the same surgeons. Intraclass correlation coefficients (ICCs) were calculated.The mean force applied to the spreader device was 148N (127-169N). A new device, constantload dynamic gap measurer, was developed on the basis of the biomechanical tests. This devicecan load constant distraction force up to 200 N. The ICCs of the cadaveric feasibility testingusing the new device ranged from 0.712-0.740.The constant load dynamic gap measurer can enable the surgeon to properly evaluate the softtissue balance throughout the range of motion during TKA with acceptable reproducibility. Thismeasurer was applied for a Korean patent 10-2009-0112146.Poster: 53The Innovative EOS System for the Study of Total Hip ArthroplastyPatients : A Pioneering Experience in 200 Cases*Jean Yves Lazennec - APHP SALPETRIERE - Paris, FRANCEMarc Antoine ROUSSEAU - hopital la pitie - paris, franceAlfonso RANGEL - hopital la pitie - paris, franceVicente GONZALBES - hopital la pitie - paris, franceSamir Chabane - hopital la pitie - paris, franceYves CATONNE - hopital la pitie - paris, francefile:///E|/ISTA2010-Abstracts.htm[12/7/2011 3:15:47 PM]