Keywords: تثبیت ایلایا; Spinopelvic instrumentation; Spinal-pelvic instrumentation; Spinopelvic fixation; Bilateral lumbopelvic fixation; Sacroiliac screws; Lumbosacral fixation; Iliac screw; Iliac fixation; Spondylopelvic dissociation; Sacral kyphotic deformity;