Objective Stable internal fixation of sacral fractures after anatomic reduction of the vertical displacement. Decompression of nerve roots. Early return to pain-free function. Indications All vertically unstable sacral fractures of type C pelvic ring disruptions. Sacroiliac dislocations. Contraindications Compound fractures. Soft tissue detachment of posterior pelvic ring or fractures associated with considerable soft tissue trauma constitute a contraindication limited to the immediate post-injury phase given the risk of infection and soft tissue complications. Surgical Technique Curvilinear or paravertebral posterior approach. Reduction of the fracture, stabilization between pedicle of L4 or L5 and posterior aspect of the iliac bone or the sacral wing lateral to the sacral fracture. Thereafter, iliosacral screw fixation (unilateral fractures with little displacement) or transsacral plate fixation (bilateral fractures or unilateral fractures with marked displacement). If a stabilization of the anterior pelvic ring has been performed, 1 iliosacral screw is sufficient, otherwise 2 screws should be used. Stabilization of the anterior pelvic ring is only indicated in the presence of disruption of the symphysis, marked displacement of fragments, or if associated injuries necessitate an anterior approach. Results Since April 1992, vertically unstable sacral fractures were treated with this stabilization in 48 patients (average age 34 years, range 15 to 72 years). Since 1994, the start of postoperative full weight-bearing was gradually advanced. Despite the immediate postoperative full weightbearing, a loss of reduction was not observed in properly performed triangular internal fixation. An incomplete reduction associated with an inadequate stabilization led to a loss of correction in 3 patients. Prominent heads of pedicle screws at the level of the posterior iliac crest may cause soft tissue problems. All fractures consolidated. Implant removal was performed in 23 patients, in 1 patient on account of deep infection and in 22 after consolidation of the fracture. Out of 25 patients with preoperative neurologic deficit, 4 showed a complete and 3 a partial recovery.