In this 3-year follow-up study of 66 community-dwelling adults with severely deformed vertebral fractures, the annual incidence of adjacent vertebral fracture (AVF) was 6.1%/year. Lower bone mineral density at the femoral neck and spinopelvic malalignment were risk factors for AVF.
Purpose: This study aimed to clarify the incidence and risk factors of adjacent vertebral fractures (AVFs)-fractures adjacent to a prevalent vertebral fracture (VF)-using an established population-based cohort from the ROAD study.
Methods: Among the 1213 participants who underwent whole-spine radiography in ROAD's third (2012-2013, the baseline) and fourth surveys (2015-2016, the follow-up), 66 (12 men, 54 women) had at least one VF at the baseline. VF and AVF were determined radiographically using Genant's semi-quantitative (SQ) method, where VF was SQ ≥ 2 and AVF was a one-level cranial or caudal vertebra with an SQ grade one or more higher at the follow-up. An interviewer-administered questionnaire was applied, and anthropometric measurements and bone mineral density (BMD) measurements at the lumbar spine and femoral neck were performed. Sagittal imbalance of the spine was defined as a mismatch between pelvic incidence and lumbar lordosis (PI-LL) of > 20°. Multivariate logistic regression analyses were performed to identify risk factors for AVF.
Results: AVF occurred in 12 participants (1 man, 11 women). The annual incidence of AVF was estimated at 6.1%/year. Logistic regression analyses revealed that lower BMD at the femoral neck and PI-LL > 20° were risk factors for AVF.
Conclusions: The annual incidence of AVF in a general population with prevalent VF was 6.1%/year. In addition, lower BMD at the femoral neck and PI-LL > 20° were risk factors for AVF.
Keywords: Adjacent level; Bone mineral density; Incidence; Sagittal alignment; Vertebral fracture.