Restoration of Femoral Condylar Anatomy for Achieving Optimum Functional Expectations: Component Design and Early Results
BACKGROUND: Many total knee arthroplasty (TKA) systems are used across a variety of markets in which outcome will be influenced by patient morphology and normal activities of daily living, for that patient population. Femoral component sizing in primary total knee arthroplasty is of paramount importance for optimizing complication free post-operative function across all patients. The purpose of this study was to report the early results of a primary TKA system in support of the component design characteristics for achievement of increased functional expectations.
METHODS: A prospective, continuous series of 176 primary posterior stabilized (PS) TKAs were performed in 172 patients by a single surgeon. Femoral component size distribution was assessed and all patients were followed for a minimum of two-years post-operatively. Total Hospital for Special Surgery (HSS) scores and range of motion (ROM) was assessed for the entire cohort and by gender.
RESULTS: There were no patients lost to follow-up. Two patients required incision and drainage for superficial wound infection of the indicated knees. There was no radiographic evidence of component failure. As expected, femoral component size frequency use was skewed by gender with the larger sizes in males. There were no pre- or post-operative clinical or functional differences by gender and at the recent follow-up (avg. 3.8 years). In addition, there was an average significant increase in change of HSS score (p<0.01) and ROM (P<0.01) when compared to pre-operative baseline.
CONCLUSIONS: The design characteristic for component sizing and functional expectations were confirmed in the reported Western population cohort series. Further continued use and study of this primary TKA system is warranted across all ethnic cultures.
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