Application of second sacral alar-iliac screw technique for reconstruction of spinopelvic stability

Abstract

To summarize the current research progress of second sacral alar-iliac (S 2AI) screw technique for reconstruction of spinopelvic stability. The recent original literature concerning development, clinical applications, anatomy, imageology, and biomechanics of S 2AI screw technique in reconstruction of spinopelvic stability was reviewed and analyzed. As a common clinical strategy for the reconstruction of spinopelvic stability, S 2AI screws achieve satisfactory effectiveness of lumbosacral fixation without complications which were found during the application of traditional iliac screws technique. S 2AI screw technique is more difficult to place screws by hand because of its narrow screw trajectory. Although the S 2AI screws trajectory pass through 3 layers of bone cortex, the biomechanical cadaveric study demonstrate that no statistical difference in stiffness was found between the traditional iliac and S 2AI screw in a spinopelvic fixation model. S 2AI screw technique should be a safe and feasible method for reconstruction of spinopelvic stability in place of the traditional iliac screw technique.