Unicompartmental knee arthroplasty (UKA) has been shown to have many benefits over conventional Total Knee Arthroplasty (TKA), but has also been shown to be technically difficult. In fact, technical error is the most common cause of premature failure in UKA. Bicompartmental arthroplasty (BKA) has the potential to perform like TKA with the benefits of UKA. We describe the initial experience with customized alignment guides and implants for UKA and BKA, manufactured based upon preoperative CT scan. Twenty three implants in 19 patients were implanted and followed for a minimum of three months postoperatively. Knee society scores and SF-12 scores were collected preoperatively and postoperatively. Radiographs were analyzed with image analysis software for malposition and loosening.INTRODUCTION
MATERIALS AND METHODS
we have previously reported that bone preparation is quite precise and accurate 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 tibial implant position, presumably occuring during cement curing. In this study, we reviewed a subsequent cohort of patients in which the tibial and femoral components were cemented individually with ongoing evaluation of tibial component position during cement curing. Group 1 comprised the simultaneous cementing techniquegroup 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 each cohort of patients were evaluated using image analysis software. Statistical evaluation was performed.INTRODUCTION
METHODS AND MATERIALS
