The Trans Iliacal Internal Fixator (TIFI) is a minimally invasive technique for the stabilization of sacro-iliac joint ruptures and fractures lateral to the sacral ala or through the sacral foramen. In this study, 7.0 mm pedicle screws of the Universal-Spine-System (USS, Synthes) were inserted 1-2 cm on the cranial side of the posterior superior iliac spine and parallel to the superior gluteal line. The connecting bar was inserted subfascially and fixed with the locking head pedicle screws to form an fixed-angle construction. In a prospective study 31 patients with vertical shear injuries of the pelvis were treated with the TIFI. There were two wound infections and one loosening of a pedicle screw. None of the screws were incorrectly positioned and no neuro-vascular lesions were caused by the implant. 2 years postoperatively we found 50% good and excellent results for type C pelvic ring injuries. Early findings show that the TIFI is well suited to stabilization of sacro-iliac joint ruptures and fractures of the lateral sacrum. Closed reduction and minimally invasive insertion technique are possible. The implant leads to sufficient biomechanical stability but there is a very low intraoperative risk of neuro-vascular lesion.