Surgical Treatment of Congential Scoliosis-Validity of Pedicle Screws

Kim, Won Joong; Suk, Se Il; Lee, Choon Ki; Lee, Ji Ho; Cho, Kyu Jung; Oh, Joo Han

Abstract

Surgical treatment of congenital scoliosis is often frustrating due to its severity and rigidity. Many surgical methods were provided for these complex deformities and some instruments were used to achieve better correction. However, no surgical treatment was satisfactory to correct the deformities. Recently, pedicle screw fixation, enabling a powerful grip of individual vertebral segment, is becoming a promising method to enhance correction of these tenacious deformities. This study was to compare the correction, loss of correction and complications of the various surgical methods employed for congenital scoliosis in Seoul National University Hospital and to verify the advantages of pedicle screw fixation. Ninety-two congenital scoliosis subjected to surgery and followed up for more than 2 years(range 2-9 years) were analysed. Surgical methods were; anterior uninstrumented fusion, 5; posterior fusion, 50(14 without instrument, 15 with hooks, 21 with screws); combined anterior and posterior fusion, 37(7 without instrument, 11 with posterior hooks, 10 with posterior screws, 9 with anterior VDS and posterior screws). Mean preoperative magnitude of index curve was 58° with no significant difference between the groups except for the anterior VDS and posterior screw group which had a mean magnitude of 93°. Mean flexibility of index curve was 18.7% with no significant difference between groups. The correction of index curves were; anterior uninstrumented fusion, 23%; posterior uninstrumented fusion, 28%; posterior hook, 31%; posterior screw, 46%; combined anterior and posterior uninstrumented, 37%; anterior fusion and posterior hook, 30%; anterior fusion and posterior screw, 47%; anterior VDS and posterior screw, 48%. The correction of pedicle screws were significantly better(p < 0.01) with significantly smaller loss of correction(p < 0.01). Nonunion occurred in 4, 1 in posterior uninstrumented fusion, 2 in posterior hooks and 1 in posterior pedicle screws with concomitant instrument failures. However, there were no neurologic or visceral complications related to screw placement. Pedicle screw fixation offers an enhances correction of congenital scoliosis with low complication rate, and when combined with an anterior procedure, enables control of the most severe and rigid curves.