Results of Compensating Spine Fusion in Children with Spine Deformities Associated with Vertebral Segmentation Disorder of the Thoracic Spine

Abstract

Objective. To analyze results of compensating spine fusion in children aged 1 to 3 years with vertebral segmentation disorders of the thoracic spine. Materials and Methods. Forty children with asymmetric (lateral) segmentation disorder in the thoracic spine underwent anterior-lateral fusion on the side opposite to a vertebral block. In 3 children the fusion was supplemented with rib synostosis on the side opposite to vertebral block. Dynamics of the primary curve, thoracic spine sagittal alignment, deformity progression rate before and after surgery, and changes in left and right hemithorax volumes, SAL index and thorax asymmetry index were followed up. Results. Mean rates of deformity progression correlate with the extension of congenital block and the amount of segments included in compensating spine fusion. Progression rate decreased by more than 50 % in 10 children having the number of surgically fused segments exceeding the number of congenitally unsegmented vertebrae. In 8 children with equal number of congenitally and artificially blocked segments the rate of deformity progression decreased by 44 %. Compensating spondylosyndesis did not influence the thorax deformity. Conclusion. The rate of spinal deformity progression after compensating spine fusion depends on the length of unsegmented rod and the number of artificially blocked segments on the opposite side.