This study examined the factors affecting pain, the pattern of pain, as well as the intensity and duration after a total knee arthroplasty.

As a prospective study, 69 osteoarthritic knee patients who underwent total knee arthroplasty from Jan. 2004 to Nov. 2004, were examined using a visual analogue scale (VAS) in order to determine the pain intensity, duration, pain character and pattern at 6 weeks, 3 months, 6 months and 1 year after surgery. We checked for possible factors such as height, body weight, body mass index (BMI), HSS score, deformity, range of motion preoperatively, prosthesis type and operation procedure intraoperatively, the HSS score and range of motion at postoperative one year. The Pearson correlation test and Kruskal-Wallis test were used for statistical analysis.

The mean preoperative and 1-year postoperative HSS score was 61.4 and 94.6, respectively. The height, body weight, body mass index (BMI), HSS score, deformity, range of motion, prosthesis type and surgical procedure were not related to the intensity and duration of the pain. The mean postoperative VAS score at 6 weeks and 3, 6 and 12 months was 4.3±1.0, 2.7±0.9, 1.6±0.4, 1.3±0.4, respectively. Five patients had mild pain until postoperative one year.

The pain after total knee arthroplasty disappeared with time. However, mild knee pain sometimes remained even 1 year after surgery.