Objectives: To investigate the relationship between the preoperative coronal intervertebral angle changes and postoperative trunk shift (TS) in patients who received congenital scoliosis correction.
Methods: The data of 921 patients with congenital scoliosis, who received posterior congenital scoliosis correction and internal fixation, was retrospectively analyzed. Anteroposterior (AP) whole spine standing radiographs and right and left lateral bending radiographs were taken preoperatively, and AP whole spine standing radiographs were obtained postoperatively and at the final follow-up. TS was measured in the coronal plane, and intervertebral angle change was the sum of the absolute values of L4-S1 intervertebral angle changes in the coronal plane, and was determined before surgery, postoperatively, and at final follow-up.
Results: A total of 38 patients with a mean age of 16.42±8.36 years old and a mean follow-up of 12.4 months (range, 6 to 36 months) were included. A median negative correlation were found between TS at the final follow-up and total variance of bending (r=-0.51, P=0.001). Groups were defined by two methods: coronal intervertebral angle changes ≥10° or <10°, and final follow-up TS < 20 mm or ≥ 20 mm. TS at the final follow-up was significantly greater in the <10° group than the ≥10° group (32.45 vs 12.44 mm, P=0.001), and coronal intervertebral angle changes was significantly greater in the TS < 20 mm group than the ≥ 20 mm group (14.2° vs 6°, P=0.001).
Conclusion: Postoperative TS which will not compensate spontaneously can be predicted by measurement of the preoperative intervertebral interspace angle in the congenital scoliosis lumbosacral region.