Comparison of acute single versus multiple osteoporotic vertebral compression fractures in radiographic characteristic and bone fragility

BACKGROUND: Osteoporotic vertebral compression fractures (OVCF) are common in aged population with bone fragility. This study aimed to identify the radiographic and bone fragility characteristic of acute single and multiple OVCF. METHODS: OVCF patients hospitalized in a spine center between June 2016 and October 2020 were retrospectively studied. Demographics, comorbidity, bone mineral density, spine trauma, duration of pre-hospital back pain, anatomical location and distribution pattern of OVCF, extent of vertebral marrow edema, and degree of vertebral compression of patients with multi-segment vertebral fractures (MSVF) were summarized and compared to those with single segment vertebral fractures (SSVF). RESULTS: A total of 1182 patients with 1530 acute fractured vertebrae were included. There were 944 SSVF (79.9%) and 238 MSVF (20.1%) simultaneously involving two (MSVF-2) or three and more vertebra (MSVF-3/m). The Female-Male ratio was 4.4 and differed not significantly between SSVF and MSVF. Females in SSVF were younger than males while MSVF-2 tended to occur in older females. L1, T12, and L2 were the three most frequently fractured vertebra and MSVF involved more vertebra in thoracic and lumbar spine. 31.1% in MSVF-2 and 83.1% in MSVF-3/m had at least two vertebral fractures in adjacent. The fractured thoracolumbar vertebra in MSVF was less compressed than that in SSVF. Apparent spine trauma was reported by 61.4% of SSVF, 44.1% of MSVF-2, and 36.3% of MSVF-3/m, while early hospitalization with pre-hospital back pain ≤ 1 week was 58.9% in SSVF, 45.3% in MSVF-2, and 25.9% in MSVF-3/m. Only females aged 70–80 years old in MSVF-3/m showed lower baseline bone mineral density than in MSVF-2 and SSVF. MSVF were not associated with increased comorbidity of hypertension, diabetes, coronary heart disease, cerebral infarction, and chronic pulmonary disease. CONCLUSIONS: 20% of acute OVCF can involve multiple vertebra without significant spine trauma or lower baseline bone mineral density. Multiple OVCF tend to occur in adjacent vertebra with less thoracolumbar vertebral compression but longer duration of pre-hospital back pain.