Risk factors affecting vertebral collapse and kyphotic progression in postmenopausal osteoporotic vertebral fractures

We aimed to investigate the risk factors that affect vertebral deformity 6 months after osteoporotic vertebral fractures (OVFs) at the time of injury. From May 2017 to May 2020, 70 postmenopausal women with OVFs were evaluated for age; body mass index; number of previous OVFs; total 25-hydroxy vitamin D [25(OH)D] levels; posterior wall injury on computed tomography; cross-sectional area (CSA) of the psoas major, erector spinae, and multifidus; fat infiltration; vertebral instability (VI) upon admission; collapse rate (CR); and kyphotic angle (KA) at 6 months after injury. A multiple regression analysis was conducted to identify the risk factors for the CR and KA. The CR was correlated with posterior wall injury (r = 0.295, p = 0.022), 25(OH)D levels (r =  − 0.367, p = 0.002), and VI (r = 0.307, p = 0.010). In the multiple regression analysis, the 25(OH)D levels (p = 0.032) and VI (p = 0.035) were significant risk factors for the CR at the 6-month follow-up. The KA was correlated with the 25(OH)D levels (r =  − 0.262, p = 0.031) and VI (r = 0.298, p = 0.012). In the multiple regression analysis, the CSA of the psoas major (p = 0.011) and VI (p < 0.001) were significant risk factors for the KA at the 6-month follow-up. In cases with large VI at the time of injury, the CR and KA were significantly higher at 6 months after injury. Moreover, the CR was affected by the 25(OH)D level, while the KA was affected by the CSA of the psoas major upon admission.