Correlation study between KSS, WOMAC and SF-36 scores in patients undergoing total knee arthroplasty in a Spanish speaking population.

The aim of this study was to determine whether it is necessary to use the KSS, WOMAC and SF-36 scales in a Spanish speaking population. These 3 questionnaires were administered to 1000 consecutive patients in the TKA preoperative period. Pearson's correlation coefficient and coefficient of determination were obtained. 196 patients were excluded. A poor correlation was obtained comparing the different items of the different scores with each other. Only in 3 out of different comparisons performed was a Pearson's correlation r>0.5 obtained. The worst results were obtained comparing the two knee specific tests (SF-36 vs WOMAC) and the best ones comparing SF-36 and WOMAC scores. Based on these results, the use of the three tests in the TKA preoperative period is recommended in a Spanish speaking population.