Abstract
Introduction
Improving cosmesis is an important aim of the AIS surgery. Anterior and posterior instrumentations are two established methods of correcting Lenke 5C AIS. Both methods have respective advantages and disadvantages. However, there was no detailed report in the literature focusing on the comparison between the cosmetic and radiographic outcomes of these two methods. The objective of this study is to evaluate and compare the cosmetic and radiographic outcomes of anterior versus posterior instrumentation in Lenke 5C AIS.
Materials and Methods
A retrospective analysis was conducted in 68 consecutive female Lenke 5C patients who had surgery between 2006 and 2010. Thirty-two patients had anterior surgery (Group A) and 36 patients had posterior surgery (Group B). Patients were evaluated at a minimum follow-up of 2 years. Cobb angles, apical vertebral translation (AVT), and apical vertebral rotation (AVR) were measured in the standard long-standing posteroanterior radiographs. Waistline height index, waistline depth index, waistline area index, waist area index, and hump index (α) were measured clinically and the five parameters combined into a composite cosmetic index (CCI). Cosmetic and radiologic outcomes of both Groups A and B were evaluated and compared.
Results
The mean age, preoperative CCI, major curve magnitude, number of levels involved in the major curve, AVT, and AVR were similar for the anterior and posterior groups (age: 16.25 vs. 16.00 years; CCI: 53.76 vs. 52.65; curve size: 45.67 vs. 46.33 degrees; number of levels: P50 = 5 vs. P50 = 5; AVT: 17.39 vs. 18.40%; AVR: 2.13 vs. 2.24 degrees). There were significant increases noted in terms of correction of CCI before and after surgery in both groups (p < 0.001). Average coronal correction of major curves was 89% at follow-up in Group A and 87% in Group B. No significant differences were observed regarding correction of CCI, Cobb angle, and AVT at last follow-up between both groups (p > 0.05). However, significant differences were noted in Group A with regard to shorter fusion levels (p < 0.001) and improved correction of AVR (p < 0.05). There were no complications in either group which extended hospital stay or required an unplanned second surgery.
Conclusion
Anterior versus posterior surgery comparison in treating Lenke 5C AIS did not show any significant differences with regard to cosmetic and lumbar/thoracolumbar curve correction, but demonstrated shorter fusion levels and improved correction of vertebral rotation in anterior instrumentation group.