Total hip arthroplasty in patients 50 years or less: do we improve activity profiles?

The primary objective of this study was to use step activity monitoring to quantify activity changes after total hip arthroplasty in patients 50 years or less. Secondly, we investigated whether step activity measurements correlated with the Harris hip and UCLA scores. We prospectively analyzed 37 patients (age ≤ 50) treated with primary THA. Patient activity was recorded with a step activity monitor. Harris hip and UCLA scores were analyzed. Total daily stride counts increased by an average of 30.0%. Increases were noted in the percent of daily time spent at high, moderate and low activity. Increases in daily time spent at high activity moderately correlated with the UCLA activity score but did not correlate with the HHS. Both the UCLA score and the HHS did not correlate with mean daily strides. Following THA, patients ≤ 50 years of age increase their activity by taking more daily strides and improve their activity profile by spending more time at higher activity. Improvements in step activity moderately correlate with improvements in UCLA scores.