Table 1: Patient demographics.

Characteristic variableTotal hip arthroplasty
mean (standard deviation)
Total knee arthroplasty
mean (standard deviation)

Number of patients87103
Age at surgery63.1 years (SD ± 14.3 years)65.1 years (SD ± 11.3 years)
Length of stay2.82 days (SD ± 1.02 days)2.59 days (SD ± 0.69 days)
Body mass index (BMI)29.2 kg/m2 (SD ± 6.13)30.7 kg/m2 (SD ± 5.99)
ASA score2.72 (SD ± 0.54)2.82 (SD ± 0.54)