[Therapy of unstable sacrum fractures in pelvic ring fractures with dorsal sacrum distraction osteosynthesis].

Unstable pelvic ring injuries AO type C ("vertical shear") with a fractured sacrum are treated operatively in less than 50% of the cases (DGU pelvis study group). Furthermore, only 12% of these ORIF involve the sacrum bone itself. No specific technique has gained wide acceptance in treating transsacral instability. In accordance with earlier publications (Käch, Josten) suggesting an internal fixator, we developed the dorsal sacrum fracture distantly anchored ORIF (DSDO). This procedure closes the dorsal pelvic ring by joining the two dorsal iliac crests (fixed-angle screws inserted in the posterior superior iliac spine) and additionally anchors in a lumbar pedicle. Thus, a three-dimensional reduction and stable fixation device with optional local nerve decompression and even plating possibility is achieved. Between January 1996 and July 2001, 35 unstable sacrum disruptions were treated with DSDO in 180 patients operated for pelvic trauma. This allowed immediate mobilization in all cases. The radiologic follow-up examination ( n=20) revealed a solid union in all patients. Complications focused on management of the soft tissue degloving injury (Morel-Lavalleé lesion), which needs special attention.