Osteoporotic Patients with Thoracolumbar Scoliosis Are at Higher Risk for Developing Thoracolumbar Spinal Fractures: A 7,000 Patient Population Cross-Sectional Study.

Background: Adult spinal deformity (ASD) is a 3-dimensional deformity that may compromise spinal stability. We hypothesized that this instability increases the risk of spinal fractures in patients with ASD. Methods: This observational, cross-sectional cohort study was conducted at a single university hospital. All patients aged 40 years or older who underwent DEXA scans over a 3-year period were included. Clinical and radiological data were analyzed using SPSS software. Results: A total of 7,075 patients (6,476 females, 599 males) were included. The mean age was 60.7 ± 10.7 years, and the mean T-score was -1.11 ± 1.38. Among these, 970 (13.7%) were osteoporotic and 645 (9.1%) had scoliosis. Spinal fractures were identified in 202 patients (2.9%) of whom 67 (33.1%) had scoliosis. Approximately 75% of these fractures occurred above the apex of the scoliotic curve, and 16% occurred at the apex itself. Multivariate analysis identified several independent risk factors for spinal fracture: increasing age (odds ratio [OR] = 1.12, 95% confidence interval [CI]: 1.09-1.15, p = 0.00), Chinese ethnicity (OR = 2.64, 95% CI: 1.07-6.55, p = 0.036), osteoporosis (OR = 1.68, 95% CI: 1.33-2.12, p < 0.001), and scoliosis (OR = 5.37, 95% CI: 3.96-7.28, p < 0.001). Subgroup analysis showed a progressive increase in fracture risk with greater Cobb angles: 10° to 20° (OR = 4.78, p < 0.01), 21° to 30° (OR = 4.95, p = 0.005), and >30° (OR = 6.14, p = 0.043). The risk increased to 31.3 times when the patient was female, osteoporotic, and had a Cobb angle ≥30° (OR = 31.3, 95% CI: 18.1-44.7, p = 0.05). Conclusion: To the best of the author's knowledge, this is the first large study to describe lumbar scoliosis as an independent risk factor for spinal fracture. Although patient's age, race, and sex may be risk factors for the development of spinal fractures, the presence of lumbar scoliosis significantly increases the risk, especially in patients with osteoporosis. The risk of developing spinal fracture increases to 31.3 times if the patient is female, has osteoporosis, and Cobb angle ≥30°. This study serves to alert the physician that elderly osteoporotic patients with thoracolumbar/lumbar scoliosis are at higher risk of developing spinal fractures, and careful follow-up with aggressive treatment of osteoporosis may be required. Level of Evidence: Level III. See Instructions for Authors for a complete description of levels of evidence. Clinical Relevance: Elderly female osteoporotic patients with thoracolumbar/lumbar scoliosis are at higher risk of developing spinal fractures. Careful follow-up with aggressive treatment of osteoporosis may be required.