Unicompartmental knee arthroplasty (UKA) has been proven to be an effective treatment for degenerative joint disease confined to a single tibiofemoral compartment. Recently, UKAs have been performed with robotic-arm assistance (RAA) devices to build and improve upon previous computer-assisted navigation. As a pilot study, we have analyzed short term outcomes for a series of robotic-arm assisted medial UKAs and compared them to a comparable cohort of traditionally instrumented medial UKAs. Ninety-eight fixed-bearing medial UKAs were isolated in our prospective data collection database for short-term analysis for this study. Included patients completed pre and post-operative Short Form 12 version 1 Health Survey (SF12), Western Ontario and McMaster University Outcome Scores (WOMAC), and Knee Society Function Score (KSFS) questionnaires. Forty-eight RAA UKAs were performed using the MAKO RIO system with Restoris implants, and fifty manual UKAs were performed with the Zimmer® Unicompartmental High-Flex Knee System (ZUK).Introduction:
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Indications for UKA for isolated osteoarthritis of the knee remain controversial. 229 UKA that were performed at our institution were evaluated for which factors was associated with a poor outcome. BMI > 35 was correlated with lower KSS scores than patients with BMI < 35. In contrast to prior reports, patients younger than 60 years old had higher scores than patients 60 years and older at 2 years. Women had an unacceptably high short-term revision rate for any reason of 6.5%. Popularity for UKA has increased, and a more in depth investigation of predictors of poor outcomes demonstrates that younger patients appear to have better results. Obese patients continue to improve up to 2 years after surgery and should not be precluded from undergoing UKA.
The study is a prospective series of the functional outcomes of total knee arthroplasty (TKA) with a novel bi-cruciate stabilizing prosthesis (BCS TKA) compared to a Posterior stabilized (PS) TKA. Between 2008 and 2012, 63 BCS TKA were performed on 56 patients (71 knees) and 54 patients underwent 56 PS TKA with a primary diagnosis of degenerative osteoarthritis, all performed by a single surgeon. Patients completed the Short-Form 12 and WOMAC Index questionnaires pre-operatively and post-operatively at 3 months, 1 year, and 2 years with range of motion determined in the office setting. Regarding the BCS knees, significant improvements in post-operative range of motion were noted, and results of the WOMAC pain component were promising at all intervals tested. However, measures of overall knee function including the WOMAC physical function and stiffness scores in addition to Knee Society Functional Scores saw a slight decline during the second post-operative year. Results from the PS knee implants showed similar trends, and no statistically significant differences were found between the two cohorts throughout functional follow-up; however the ranges of motions appear to be increased in the BCS knee cohort.
