Dual Growing Rods for the Treatment of Early-Onset Scoliosis.

Abstract

The dual growing-rod technique involves implantation of a set of two rods and two anchor groups (upper and lower foundations) to exert frequent distractions to allow for spinal growth. Pay special attention to the effect of positioning on sagittal alignment. Use multimodality intraoperative neuromonitoring, including SSEPs, MEPs, EMG, and H-Reflexes. Avoid broad exposure of uninstrumented levels to prevent the risk of spontaneous fusion. The foundation is an assembly of at least four anchors at two or three vertebrae along with one or two rods. Use hooks or pedicle screws for the proximal foundation and use bilateral pedicle screws (a four-anchor construct) for the distal foundation. Cut two 4.5-mm rods and contour them to the appropriate sagittal and coronal alignment, being careful not to overcorrect in the sagittal and coronal planes. Place a tandem connector at the thoracolumbar junction to allow for future lengthening. Pass the preassembled rods and tandem connector from caudad to cephalad beneath the fascia, securing them to the foundation and performing the first lengthening. Gentle handling of the skin and associated deeper tissues is essential to avoid complications. These are the same as those for the initial surgery. Make one incision between the two connectors on or in line with the original incision. Lengthening can be performed inside or outside the tandem connector. See Step 9 for the initial surgery. The quantity and quality of research on growth-sparing techniques for early-onset scoliosis have increased substantially in the past three years. IndicationsContraindicationsPitfalls & Challenges.