Several posterior fixation techniques for unstable pelvic ring fractures have been described. Here, we present a minimally invasive, percutaneous technique to fix the two posterior iliac crests using spinal instrumentation. Between September 2008 and March 2012, 11 patients with a mean age of 36.4 years were operated because of a vertically unstable Tile C pelvic ring fracture. Posterior fixation was performed using two polyaxial screws in each iliac crest with two subfascial connector rods. At the final follow-up, all patients were evaluated clinically and radiologically. The mean surgery time was 45 minutes; there were no intraoperative complications. At a mean follow-up of four years, the functional Majeed score was excellent in eight patients and good in three patients. The radiological results were excellent in eight patients and good in three patients. Percutaneous posterior fixation of vertically unstable pelvic fractures leads to good functional and radiological outcomes. TYPE OF STUDY Technical note, retrospective. LEVEL OF EVIDENCE IV.