Incidence and risk factors for hip fracture in elderly patients undergoing lumbar spine surgery: a nationwide database study with 11-year follow-up

Summary Impaired functional movement may occur after spinal surgery, which increases risk of fall episode and hip fracture. Patients with long-segment thoracolumbar spine fusions had a significantly higher risk of hip fracture than those with only discectomies. Fall prevention is necessary due to the highly increased hip fracture risk. Introduction Spinal surgeries are performed to treat spondylolisthesis, fractures, scoliosis, or other deformities. Impaired balance mechanisms and functional movement may occur after spinal surgery. Fall episodes may cause hip fractures, which have negative impacts on quality of life and increase mortality. The incidence of hip fracture after spinal surgery is still unknown. The aim of this study was to examine the association between various types of spinal surgeries and hip fractures in the elderly by using a nationwide database. We hypothesized that the spinal surgeries may increase hip fracture risk in the elderly. Methods We used the National Health Insurance Research Database (NHIRD) to identify 3345 patients undergoing spinal surgery and a random dataset to identify 6690 age-, sex- and Charlson comorbidity index (CCI)-matched controls to compare the incidence of hip fractures in an 11-year follow-up period. We also enrolled 82,730 patients with spinal surgeries from the inpatient dataset to investigate the impact of different types of spinal surgeries. Results Patients who received spinal surgeries had higher risks of hip fractures, especially patients aged 60 to 79 years and female patients. The patients with long-segment thoracolumbar spinal fusions had a significantly higher risk of hip fracture than those with only discectomies. Short segmental lumbar spine fusions also slightly increased the risk of hip fracture compared with discectomies. Conclusion Fall prevention for the elderly undergoing lumbar spinal surgery is necessary due to the highly increased hip fracture risk.