The influence of ageing on the incidence and site of trauma femoral fractures: a cross-sectional analysis

BACKGROUND: This study aimed to determine the influence of ageing on the incidence and site of femoral fractures in trauma patients, by taking the sex, body weight, and trauma mechanisms into account. METHODS: This retrospective study reviewed data from adult trauma patients aged ≥20 years who were admitted into a Level I trauma center, between January 1, 2009 and December 31, 2016. According to the femoral fracture locations, 3859 adult patients with 4011 fracture sites were grouped into five subgroups: proximal type A (n = 1359), proximal type B (n = 1487), proximal type C (n = 59), femoral shaft (n = 640), and distal femur (n = 466) groups. A multivariate logistic regression analysis was applied to identify independent effects of the univariate predictive variables on the occurrence of fracture at a specific site. A two-dimensional plot was presented visually with age and the propensity score accounts for the risk of a fracture at a specific femoral site. RESULTS: This analysis revealed that older age was an independent variable that could positively predict the occurrence of proximal type A (OR [95%CI]: 1.03 [1.03–1.04], p < 0.001) and B fractures (1.02 [1.01–1.02], p < 0.001), and negatively predict the occurrence of proximal type C (0.96 [0.94–0.98], p < 0.001), shaft (0.95 [0.95–0.96], p < 0.001), and distal fractures (0.98 [0.98–0.99], p < 0.001). DISCUSSION: Using the propensity scores which account for the risk of a fracture in a specific femoral site, this study revealed that the older patients were at a higher risk of developing proximal type A and type B fractures, while a lower risk of developing fractures in the shaft and distal femur. This incidence of fracture site can largely be explained by age-related factors, including a decrease in bone strength and falling being the most common mechanism of trauma in older patients. CONCLUSIONS: This study revealed a difference in the involvement of age in the incidence of femoral fracture sites in the trauma patients.