Epidemiology and surgical management of the lower lumbar spinal metastases in China: a multicenter retrospective study.

Between 2000 and 2019, data of hospitalizations with lower lumbar spinal metastasis were extracted from six medical centers in China. A total of 505 patients were identified in this study. Peak patients occurred in the group aged from 60 to 69 years, the age at diagnosis of female patients was 2.62 years earlier than that of male patients, and the proportion of male patients aged over 60 years was higher than that of females. Three most prevalent primary tumor were lung cancer, unknown origin tumor, and breast cancer. Solitary L4 metastases were nearly same as solitary L5 metastases. In terms of intervention, 347 patients (68.71%) received systemic treatment, while 158 patients (31.29%) underwent surgical therapy comprised of minimally invasive surgery (28 cases, 17.72%) and open surgery (130 cases, 82.28%). According to multivariate logistic analysis, SINS score, medical center, CCI, and segment of involved vertebrae were four independent predictors of surgical decision-making. This study represents the largest series of patients with lower lumbar metastases in the literatures. Due to several unique anatomic and biomechanical considerations with respect to metastases to the lower lumbar region, some characteristics are not completely commensurate with other spinal segmental metastases, which reinforces the significance for translation to regular clinical practice.