The position of the aorta relative to the spine in patients with adult degenerative scoliosis

STUDY DESIGN: A retrospective analysis was conducted to analyze the position of the aorta by MRI in patients with adult degenerative scoliosis. OBJECTIVE: This study aimed to investigate the relative anatomic positions of the aorta and spine in patients with adult degenerative scoliosis (ADS). SUMMARY OF BACKGROUND DATA: Aorta injury is a rare complication of spinal surgeries. However, there would be a disastrous consequence once it happened. Therefore, knowing about the position of aorta is of great importance. METHODS: A retrospective analysis was performed in 90 patients with ADS and 132 participants without spine deformity. ADS patients were divided into several groups such as left scoliosis, left scoliosis with thoracolumbar kyphosis, right scoliosis, and right scoliosis with thoracolumbar kyphosis. The aorta-vertebrae angle (α) and aorta-vertebrae distance (d) in each level of T12–L4 were measured by using a Cartesian coordinate system. t test of independent samples was performed, α and d were compared, and Pearson correlation analysis was employed for α, d, and X-ray radiographic measurements. RESULT: The changes of α were not statistically significant (P > 0.05) in LS and LKS groups but d (P < 0.05) was longer in LKS group compared with the control group. In the right malformed group, there was no significant change in the angle (P > 0.05) in the abdominal aorta but longer d (P < 0.05) than the normal group. There was longer d in the RKS group compared with the RS group (P < 0.05). Pearson correlation analysis showed that there was a positive correlation between d and TLK (r = 0.439, P < 0.05). CONCLUSION: In patients with ADS, a relative normal position is maintained between the aorta and vertebrae. While the aorta is slightly away from the left pedicle in RS patients and farther away in patients with kyphosis, the angle of kyphosis would become bigger and d becomes longer. Therefore, the surgeons should be aware of the changes of the aorta position to avoid the disastrous vessel injuries.