Impact of variation in physical activity after total joint replacement

Patients who undergo total knee arthroplasty (TKA) or total hip arthroplasty (THA) often develop postoperative pain. Exercise approaches are recommended postoperatively; however, the impact of excessive variation in physical activity is unclear. The purpose of the present preliminary study was to investigate the impact of excessive variation in physical activity using the accelerometer in the early period after TKA or THA.

Seventy-two patients were enrolled in the study. Forty patients underwent initial TKA, and 32 initial THA. Physical activity was measured for 8 days from postoperative day 3 to 10. Patients with substantial correlation between physical activity and postoperative day were classified as the "good-pacing" group. Patients with no correlation between them were classified as the "poor-pacing" group. They were also evaluated using a pain visual analog scale (VAS), pain catastrophizing scale, and hospital anxiety and depression scale.

The average age was 68 years, and 59 patients (82%) were women. The average maximum number of steps per day was 2,181. There were 45 patients with good pacing and 27 with poor pacing. The poor-pacing group showed significantly lower maximum number of steps per day, higher postoperative average VAS score, higher postoperative worst VAS score, and longer duration of postoperative hospital stay than the good-pacing group.

Patients with excessive variation in physical activity showed severe postoperative pain and prolonged postoperative hospital stay. The postoperative variation in physical activity could be an outcome for improvement in patients after lower-limb arthroplasty.