Patient activity after total hip arthroplasty declines with advancing age

Abstract

Evaluation of patient activity is essential for clinical decision making before THA. To correlate age progression to patient activity after THA, we determined the number of walking cycles of 105 patients in different age groups by decades. Patients on average performed 6144 walking cycles per day (2.24 million cycles per year). Men were more active than women. The highest activity occurred in patients between 50 and 59 years of age, with a constant decrease in activity with advancing age. However, within age groups, we observed up to sixfold differences in the number of walking cycles per day. In addition to declining activity with advancing age, higher body mass index correlated with lower step counts. The high mean measured number of walking cycles, which were even higher than those reported for subjects without an arthroplasty, suggests patients benefit from THA. Female gender, advanced age, and obesity correlated with lower activity. Owing to the high intragroup variability of our results, preoperative evaluation of patient activity levels, individual patient factors, and patient demands, should be considered in clinical practice.

Fig. 1

A photograph shows the StepWatch™ Activity Monitor (SAM) worn at the ankle.

Fig. 2

A graph shows the highest number of walking cycles per day in patients between 50 and 59 years and subsequent decline with advancing age.

Fig. 3

The correlation of declining activity with advancing age in regression analysis (walking cycles per year = −56.2 × age + 9382) is shown. CI = confidence interval.

Fig. 4

A graph shows the correlation of lower activity with higher BMI in regression analysis (walking cycles per year = −111.85 × BMI + 9212). CI = confidence interval.