Table 1. Patient Demographic Data.

Variable	Control group (n = 33)	Navigation group (n = 23)
Age (yr)	65.6 ± 13.6	71.7 ± 6.92
Sex (male:female)	5:28	5:18
Body mass index (kg/m2)	22.7 ± 3.85	24.4 ± 3.95
Bleeding (mL)	789.53 ± 641.32	862.17 ± 659.78
Operative time (min)	257.13 ± 82.45	345.65 ± 124.20
Observation period (mo)	80.6 ± 38.0	42.2 ± 23.2
Head size (mm)	29.3	31.1

Values are presented as mean ± standard deviation.