Osteoporotic vertebral compression fractures：correlation between number of fractured vertebrae and C7plumb line/sacro-femoral distance ratio / 中国组织工程研究

ABSTRACT

BACKGROUND:Sagittal imbalance induced by vertebral osteoporotic fractures has not been paid enough attention in previous studies. OBJECTIVE:To assess the correlation of osteoporotic vertebral compression fracture and spinal sagittal imbalance. METHODS:Sixty patients with old osteoporotic vertebral compression fracture, who were treated in the Department of Spine Surgery, the Affiliated Hospital of Chengde Medical Colege from February 2013 to August 2015, were enroled in this study as the observation group. Sixty healthy old people from physical examination center were enroled as the control group. The whole-spine anteroposterior and lateral X-ray films were taken in both groups. The number and the location of fractured vertebrae were recorded. Sagittal parameters of both groups including thoracic kyphotic angle, lumbar lordotic angle, T1-spinopelvic inclination angle and the C7plumb line/sacro-femoral distance (PL/SFD) ratio were measured and compared among groups. The observation group was dividedinto three subgroups according to the number of fractured vertebrae,i.e., single-vertebrae fracture subgroup, double-vertebrae fracture subgroup and above triple-vertebrae fracture subgroup. The C7PL/SFD ratio of the three subgroups was compared. The correlation between the number of fractured vertebrae and the C7PL/SFD ratio was analyzed. RESULTS AND CONCLUSION:(1) The thoracic kyphotic angle of the observation group was bigger than that of the control group (P< 0.05). The lumbar lordotic angle of the observation group was smaler than that of the control group (P< 0.05). The absolute value of the T1-spinopelvic inclination angle of the observation group (-1.81±1.48)° was smaler than that of the control group (-3.35±1.22)° (P< 0.05). The C7PL/SFDratio of the observation group was significantly bigger than that of the control group (P< 0.05). (2) In the observation group, there were 4 cases of single-vertebrae fracture, 25 cases of double-vertebrae fracture and 31 cases of above triple-vertebrae fracture. Significant differences in the C7PL/SFD ratio were determined among subgroups (P< 0.05). The number of fractured vertebrae was positively correlated with the C7PL/SFD ratio; the correlation coefficient was 0.747. (3) Results indicated that osteoporotic vertebral compression fracture can change spinal local sagittal alignment. Multiple compression fractures of vertebrae can cause spinal sagittal imbalance. The gravity center of human body shifts forward. The number of fractured vertebrae was positively correlated with the range of shift forward.