The results of this study revealed significant relationships between plain radiograph and MR images of acute phase OVFs and the incidence of nonunion. As these risk factors are defined more clearly and further validated, they may become essential assessment tools for determining subsequent OVF treatments. Patients with one or more of the earlier-described risk factors for nonunion should be observed carefully and provided with more intensive treatments.

2.

The purpose of this study was to examine factors affecting the severity of neurological deficits and intractable back pain in patients with insufficient bone union following osteoporotic vertebral fracture (OVF). Reports of insufficient union following OVF have recently increased. Patients with this lesion have various degrees of neurological deficits and back pain. However, the factors contributing to the severity of these are still unknown. A total of 45 patients with insufficient union following OVF were included in this study. Insufficient union was diagnosed based on the findings of vertebral cleft on plain radiography or CT, as well as fluid collection indicating high-intensity change on T2-weighted MRI. Multivariate logistic regression analysis was performed to determine the factors contributing to the severity of neurological deficits and back pain in the patients. Age, sex, level of fracture, duration after onset of symptoms, degree of local kyphosis, degree of angular instability, ratio of occupation by bony fragments, presence or absence of protrusion of flavum, and presence or absence of ossification of the anterior longitudinal ligament (OALL) in the adjacent level were used as explanatory variables, while severity of neurological deficits and back pain were response variables. On multivariate analysis, factors significantly affecting the severity of neurological deficits were angular instability of more than 15°[adjusted odds ratio (OR), 9.24 (95% confidence interval, CI 1.49-57.2); P \ 0.05] and ratio of occupation by bony fragments in the spinal canal of more than 42% [adjusted OR 9.23 (95%CI 1.15-74.1); P \ 0.05]. The factor significantly affecting the severity of back pain was angular instability of more than 15°[ adjusted OR 14.9 (95%CI 2.11-105); P \ 0.01]. On the other hand, presence of OALL in the adjacent level reduced degree of back pain [adjusted OR 0.14 (95%CI 0.03-0.76); P \ 0.05]. In this study, pronounced angular instability and marked posterior protrusion of bony fragments in the canal were factors affecting neurological deficits. In addition, marked angular instability was a factor affecting back pain. These findings are useful in determining treatment options for patients with insufficient union following OVF.

The MBDU can reduce postoperative segmental spinal instability and achieve good postoperative clinical outcomes in patients with DLS. The convex approach provides surgeons with good visibility and improves preservation of facet joints.

No abstract

MRI signal changes were associated with the compression degree and angular motion of fractured vertebrae. This classification showed sufficient reliability in categorizing MRI findings of OVFs.

This study demonstrated the radiological factors predicting delayed union after an OVF. T2 high-signal changes showed the strongest association with delayed union. Consecutive MRIs were particularly useful as a differential tool to predict delayed union following OVFs.

No abstract