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There was no difference in functional outcomes between UKA and BKAs. Radiographicanalysis showed that no implants overhanged bone by more than 1 millimeter in any dimension.Two of 23 tibial components were placed in greater than 10 degrees of varus (so-calledoutliers). Conversely, 9/19 tibial components were outliers placed in more than 7 degrees ofposterior slope or in reverse slope. The femoral components were designed to be placed parallelto the longitudinal axis of the femur, and 19/23 were within 3 degrees. Interestingly, there wasa tremendous amount of variation between patients. There were no postoperativecomplications. In one case, the tibial component was not completely seated to the bonepreparation level. Otherwise, there were no intraoperative complications. No revisions havebeen performed and none are pending.CONCLUSIONS. Customized implants are designed to match the patient anatomy as closelyas possible, without duplicating gross malalignment or malposition. This study shows that thistechnology reliably allows placement of UKA and BKA devices within acceptable alignmentparameters, with excellent short-term functional results. Interestingly, BKA componentsperformed as well as UKA components, suggesting that a certain percentage of traditional TKApatients can expect UKA-like function after BKA instead of TKA. Of course, much longerfollowup is required to determine rates of failure from progressive arthritis or device wear.Nevertheless, current customized UKA and BKA components are safe and effective.Thursday, October 7, 2010, 15:10-15:50Session B7: Robotic Knee SurgeryEffect of Cement Technique on Component Position During Robotic-ArmAssisted Unicompartmental Arthroplasty (UKA)*Raj Sinha - JFK Memorial Hospital - La QUINTA, United StatesMargaret Cutler - JFK Memorial Hospital - La Quinta, USA*Email: rajsinha@mac.comINTRODUCTION: we have previously reported that bone preparation is quite precise andaccurate relative to a preoperative plan when using a robotic arm assisted technique for UKA.However, in that same study, we found a large variation between intended and final tibialimplant position, presumably occuring during cement curing. In this study, we reviewed asubsequent cohort of patients in which the tibial and femoral components were cementedindividually with ongoing evaluation of tibial component position during cement curing.METHODS AND MATERIALS. Group 1 comprised the simultaneous cementingtechniquegroup of patients, previously reported on, although their x-rays were re-analyzed.Group 2 consisted of the individual cementing technique cohort. All implants were identical,specifically a flat, inlay all-polyethylene tibial component. Postoperative x-rays from eachcohort of patients were evaluated using image analysis software. Statistical evaluation wasperformed.file:///E|/ISTA2010-Abstracts.htm[12/7/2011 3:15:47 PM]