Comparison of Combined Anterior/Posterior Spinal Fusion Versus Posterior Fusion Alone for the Treatment of Adolescent Idiopathic Curves Greater than 90 Degrees

Summary: Surgical treatment of adolescent idiopathic scoliosis (AIS) curves > 90º often consists of anterior and posterior fusion (APSF) to improve coronal correction and fusion rate. However, in our study we found the use of posterior spinal fusion (PSF) alone with an all pedicle screw construct provides the same correction in patients with AIS curves > 90º as the circumferential APSF approach without the need for entering the thorax and more negatively impacting pulmonary function.

Introduction: Surgical treatment of adolescent idiopathic scoliosis (AIS) curves > 90º often consists of anterior and posterior fusion(APSF) to improve coronal correction and fusion rate.

Purpose: To assess the results of spinal fusion for AIS curves > 90º and determine whether the use of a posterior only approach with an all **pedicle screw construct can decrease the need for anterior release operations.

Methods: Fifty-four consecutive AIS patients with curves > 90º who underwent a spinal fusion procedure at one institution (1987 - 2001) with either APSF or a posterior spinal fusion (PSF) with an all pedicle screw construct were included for analysis. All patients had a minimum 2-year follow-up (mean, 6.0 years; range 2.0 to 14.5 years) and were analyzed radiographically as well as with pulmonary function tests (PFT's). Statistical analyses were performed between groups using the Wilcoxon-Mann-Whitney tests.

Results: Twenty patients were treated with a APSF, whereas 34 patients were treated with PSF. There were no statistically significant differences between the groups for gender, age, number of levels fused, preoperative Cobb measurements, curve flexibility, or amount of postoperative Cobb correction (PSF, 43.2º; APSF 39.2º). There was less effect on pulmonary function in the group treated with PSF versus the group treated with APSF (p <0 .005). There were no complications or re-operations in either group.

Conclusion: The use of PSF alone with an all pedicle screw construct provides the same correction in patients with AIS curves > 90º as the circumferential APSF approach with less negative effect on pulmonary function.

Significance: In this patient population with often restrictive preoperative pulmonary function, a posterior-only approach with the use of an all pedicle screw construct has the advantages of providing the same correction as a combined APSF without the need for entering the thorax and more negatively impacting pulmonary function.

FDA Diclosure Cleared: No ** Thoracic Pedicle Screws