Comparison of all segmental pedicle screws versus selective segmental pedicle screws instrumentation in severe rigid adolescent idiopathic scoliosis

Abstract

Objective To compare the corrective results of treatments between all segmental pedicle screws (ASPS) and selective segmental pedicle screws (SSPS). Methods A retrospective study of 48 severe rigid adolescent idiopathic scoliosis (AIS) patients under only posterior pedicle screws instrumentation and fusion in our department during March 2003 to December 2008 was made. Patients with a major thoracic curve >70° and flexibility <30% in antero-posterior standing radiograph and supine bending radiograph were screened. There were 48 patients suitable for this study selected from 327 AIS ones. Of them, 22 cases were fixed with SSPS and 26 with ASPS. Statistic parameters of age, preoperative Cobb angle of major thoracic curve, flexibility, blood loss during operation, correction rate of major thoracic curve in coronal plane one week after operation and last follow-up were compared between two groups. Results Mean age was 15.65 years and 17.32 years respectively in ASPS group and SSPS group, preoperative Cobb angle of major tho-racic curve in standing coronal plane was 86.77°±11.71° (71.31°-107.51°) and 87.56°±14.88° (70.10°- 117.83°), flexibility was 15.82%±7.37% (6.82%-29.74%)and 19.30%±9.19% (0.89%-29.71%), operation time was (280.69±35.92) min and (275.10±33.91) min, blood loss during operation was (988.50±287.80) ml and (800.98±360.47) ml, correction rate of major thoracic curve in coronal plane one week after operation were 60.07%±8.80% and 46.79%±14.90% respectively. Lose of correction was observed in one patient in ASPS group because of broken of the convex side rod. Conclusion There is a higher postoperative correc-tion rate of major thoracic curve in coronal plane of severe rigid AIS in ASPS group than in SSPS group. Key words: Scoliosis; Adolescent; Spinal fusion