Differences between Koreans and Americans undergoing Total Knee Replacement Arthroplasty for Primary Osteoarthritis

Kim, Hee Chun; Fitzgerald, Robert H; Lotke, Paul A

Abstract

BACKGROUND: Total knee arthroplasty is a reliable and durable procedure in the treatment of knee arthritis. Patient selection is one scientific aspect of total knee replacement and the surgeon must develop knowledge about those patients who will benefit from total knee replacement. Authors tried to find any differences in preoperative status for Koreans and Americans undergoing total knee replacement arthroplasty(TKRA) for primary osteoarthritis(OA). Another goal of this study was to determine whether Koreans undergoing elective TKIRA for primary OA had more advanced disease preoperatively than Americans undergoing the same procedure.
METHODS
Preoperative clinical and radiographic severity of knee OA was determined between Koreans who underwent TKRA at the National Medical Center in Seoul, Korea and Americans who underwent the same procedure at the Hospital of the University of Pennsylvania in Philadelphia, USA.
RESULTS
There were 62 women and five men included in the group I(Koreans) compared to 60 women and thirty men in the group II(Americans). The mean age for the patients in the group I was 64.0 years and for the group II 69.5 years. The average weight for the group I was 63.8 Kg(range, 46-85 kg) with an average height of 152.4 cm(range, 133-168 cm). The corresponding data in the group II was 86.6 kg(range, 54-170 kg) and 167.4 cm(range, 147-196 cm). The mean preoperative knee score(developed by The Knee Society) for the group I was 32.7 points and the mean preoperative function score was 42.0 points. The mean preoperative knee and function scores for the group II were 38.1 and 46.2 points, respectively. The mean preoperative flexion contracture and further flexion were 11.7degrees(range, 0-40degrees) and 124.8degrees(range, 70-140degrees), respectively. The corresponding data in the group II were 4.0degrees(range, 0-15degrees) and 107.7degrees(range, 80-130degrees), respectively. The group I knees had a mean preoperative tibiofemoral angle of 4.8degrees(+/-6.0degrees) varus. For the group H knees, the preoperative tibiofemoral angle was 0.83degrees(+/-7.80degrees) valgus. Lateral FT(femorotibial) osteoarthritis was not found in any Korean patients but seen in 18 cases(17.8%) of American patients.
CONCLUSION
The observed differences in the status prior to TKRA indicate that Koreans are operated on at a more advanced stage in the course of their disease than Americans. A number of important issues remain to be addressed in future research, such as the role of patient preference and different access to TKRA and the differences of their clinical presentation.