The goal of the treatment of early onset scoliosis (EOS) is correction of the deformity while still allowing for spinal growth. The aim of this study was to determine the safety and effectiveness of the single and dual growing rod techniques and which technique was the most effective in the management of EOS respectively. From 2003 to 2009,23 patients underwent single (15) or dual (8) growing rod procedures using a pedicle screw construct and tandem connectors. The etiology of the patients' spinal deformities were as follows; infantile, juvenile idiopathic, congenital and neuromuscular. Clinical evaluation included age, sex, diagnosis, follow-up, number and frequency of lengthenings, and complications. Radiographic evaluation included measured changes in Cobb angle, kyphosis, lordosis, frontal and sagittal balance. Overall 46 lengthening procedures were performed, the average number of lengthening procedures being 2.1 +/- 1.14 per patient. The average time between two lengthening procedures was 13 (2-28) months. Average follow-up time was 40.8 +/- 20.6 months. The mean coronal Cobb angle was improved from 64.8 degrees +/- 16.6 degrees to 39.7 degrees +/- 16.4 degrees. Statistically, at the final follow-up, early postoperative measurements in the coronal plane were better in the dual growing rod group than in the single rod group. Nine patients underwent fusion surgery. Their mean age was 11 (10-14) years, with a follow-up of 34.6 (14-54) months. The mean Cobb angle before fusion was 58.7 degrees (40 degrees-75). There were 0.9 complications per patient in all groups, 0.38 in the dual rod and 1.2 in the single rod group, respectively. Dual growing rods result in better deformity correction and stability of correction with an acceptable complication rate.