Gender and age differences in anatomical parameters of proximal femur in middle-aged and elderly patients with femoral intertrochanteric fracture

Objective To determine the gender and age differences in anatomical parameters of proximal femur in middle-aged and elderly patients with femoral intertrochanteric fracture so as to provide theoretical evidence for development of internal fixation devices. Methods The clinical and CT data of 375 patients with intertrochanteric fracture were analyzed retrospectively who had been treated at Department of Orthopedics, The First Medical Center, General Hospital of Chinese PLA from September 2009 to March 2017. The patients were divided into 4 age groups. The middle-aged group (from 45 to 59 years old) had 22 cases, 16 males and 6 females; the early elderly group (from 60 to 74 years old) had 87 cases, 37 males and 50 females; the elderly group (from 75 to 89 years old) had 238 cases, 76 males and 162 females; the late elderly group (≥90 years old) had 28 cases, 6 males and 22 females. The anteversion angle of femoral neck, femoral neck-shaft angle, femoral head diameter, femoral neck length, femoral neck offset and femoral neck width were measured on their images. The anatomical parameters of proximal femur were compared between genders in the same age group and between groups of the same gender. Results There were no significant differences between male and female patients with femoral intertrochanteric fracture in body mass index or AO classification, showing comparability(P>0.05). The anteversion angle of femoral neck (8.33°±5.00°) of the male middle-aged and elderly patients with intertrochanteric fracture was significantly smaller than that of the female ones (11.28°±6.15°), but their femoral head diameter, femoral neck length, femoral neck offset and femoral neck width (49.10 mm±2.48 mm, 99.70 mm±5.22 mm, 7.18 mm±2.20 mm and 39.10 mm±4.92 mm) were significantly larger than those of the female ones (43.46 mm±2.79 mm, 90.00 mm ± 4.75 mm, 6.29 mm±2.07 mm and 33.49 mm±4.87 mm) (all P 0.05). Conclusions Compared with the middle-aged and elderly male patients with femoral intertrochanteric fracture, the middle-aged and elderly female ones have a larger anteversion angle of femoral neck, smaller offset, width and length of femoral neck, and a smaller femoral head diameter. There are no significant age differences in anatomical parameters of the proximal femur in middle-aged and elderly patients with femoral intertrochanteric fracture. Key words: Hip fractures; Femur; Clinical anatomy; Gender; Imaging, three-dimensional