Risk factors of domino osteoporotic vertebral fractures is severe paraspinal muscle fatty degeneration

Domino osteoporotic vertebral fractures (OVFs) involve multiple OVFs occurring simultaneously or sequentially, before healing of the initial OVFs. However, the risk factors and long-term clinical outcomes of domino OVFs are unclear. To identify the risk factors associated with domino OVFs and to assess their impact on patients’ quality of life (QOL). Multicenter prospective observational cohort study. Patients (n = 190) treated conservatively for acute OVFs in 8 hospitals with 12-month follow-up. Clinical outcomes were assessed using the visual analog scale (VAS), Oswestry Disability Index (ODI), and Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ). Multivariate analyses were performed to identify risk factors for domino OVFs. All patients underwent magnetic resonance imaging (MRI) at 3 months to detect subsequent domino OVFs. Domino OVF group included initial domino OVFs (multiple acute OVFs at baseline) and subsequent domino OVFs at 3 months. Paraspinal muscle assessment was performed using the lumbar indentation value and Goutallier classification. Patient characteristics, bone quality, paravertebral muscle degeneration, nutritional status, radiographic parameters, and QOL scores were compared between the nondomino and domino OVF groups. We evaluated 50 (26.3%) patients with domino OVFs (34 with initial domino OVFs; 20 with subsequent domino OVFs). Walking ability was poorer in the domino than in the nondomino OVF group, from baseline to the 12 months follow-up. Groups with 3 or more adjacent domino OVFs showed worse VAS and ODI scores. Multivariate logistic regression analysis revealed that severe fatty degeneration of the paraspinal muscle was an independent risk factor for domino OVFs. Severe paraspinal muscle fatty degeneration is an independent risk factor for domino OVFs. Our study showed that the quality, rather than the quantity, of paraspinal muscles had an impact on domino OVFs. Early assessment of fatty degeneration in the paraspinal muscles is essential for predicting the development of domino OVFs.