Compensation mechanisms for post-traumatic thoracolumbar kyphosis

Abstract

Objective. To identify the mechanism of deformity compensation in patients with post-traumatic kyphosis of the thoracolumbar junction, based on the analysis of X-ray results of surgical treatment.Material and Methods. The study included data obtained from medical records of 69 patients (47 women, 22 men) operated on for painful post-traumatic kyphosis at the levels of T12, L1 and L2 vertebra. Patients underwent staged surgical interventions in a single surgical session. Demographic data and X-ray results of surgical treatment were evaluated.Results. As a result of surgical interventions, post-traumatic kyphosis (LK) was corrected to an average of 1.9°. After correction of kyphosis, statistically significant changes in the parameters of sagittal spinal curvatures were revealed: an increase in thoracic kyphosis (TK), a decrease in lumbar lordosis (LL), including due to lower lumbar lordosis (LowLL). At the same time, the parameters of the spinopelvic balance (PT, SS) did not change. Statistically significant correlations (p < 0.001) were detected between the magnitude of local kyphosis correction (LK preOP-LKpostOP), which amounted to 33.63° ± 8.77°, and parameters of lumbar lordosis ΔLL, thoracic kyphosis ΔTK and ΔPI-LL. Parameters of global sagittal balance and pelvic balance did not show correlations with the magnitude of kyphosis correction. The X-ray study of patients in Group I (without signs of initial sagittal imbalance) and Group II (with signs of sagittal imbalance) revealed a statistically significant difference in global balance (GT) and spinopelvic balance (PT, SS, LowLL), both before and after correction intervention in the thoracolumbar junction area, despite comparable indicators of sagittal spinal curvatures and the magnitude of post-traumatic kyphosis,.Conclusion. The main compensation mechanism includes changes in the spinal departments adjacent to kyphosis: a decrease in thoracic kyphosis and an increase in lumbar lordosis, rather than changes in the global or spinopelvic balance.