Posterior screw fixation in rotationally unstable pelvic ring injuries Georg Osterhoff *, Christian Ossendorf, Guido A. Wanner, Hans-Peter Simmen, Cle ´ ment M.L. Werner Department of Surgery, Division of Trauma Surgery, University Hospital Zurich, Raemistrasse 100, 8091 Zu ¨rich, Switzerland Introduction Operative treatment of pelvic ring fractures accelerates the recurrence of undisturbed gait. 13 Lateral compression fractures with rotational instability only (Young and Burgess LC I and LC II 29 or AO/Tile B2 17,23 ) are commonly treated by anterior fixation alone. 4,25 The AO manual of fracture management, as well, suggests anterior fixation alone in these fractures. 17 Yet, injuries of the anterior pelvic ring are almost always associated with injuries of the posterior pelvis 5 and the stability of the entire pelvic ring primarily depends on the integrity of the posterior sacroiliac arch. 27,2,1 Thus, Matta suggested stabilising these patients posteriorly and using internal fixation of the anterior pelvic ring predominantly in patients with symphysis pubis dislocations. 9 Objections to posterior stabilisation might arise because posterior surgical approaches to the pelvis were usually extensive and could be problematic in patients with poor soft tissue. 22 Moreover, surgery in prone position in haemodynamically unstable trauma patients and the risk of a ‘‘second hit’’ by prolonged early care must be avoided. However, with the advent of techniques like percutaneous iliosacral screw fixation, 4,12,3,15,21 early minimally invasive definitive fixation of pelvic ring injuries is possible. In an experimental setup, iliosacral screws are able to restore >80% of pre-traumatic stability of a vertical shear injury. 2 They therefore might obviate the need for additional anterior surgical stabilisation – especially when there is only rotational instability. This could be a useful alternative in patients with conditions where an extended anterior approach is of high risk or prone to complications, e.g. patients with sclerotic vessels, coagulopathy, obesity, or after hernial repair with a mesh. In the present study we evaluated the postoperative radio- graphic and clinical outcome of patients with rotationally unstable lateral compression fractures of the pelvic ring treated by iliosacral screw fixation alone. Methods Consecutive patients with rotationally unstable lateral com- pression fractures (Young and Burgess LC I and LC II 29 or AO/Tile B2 17,23 ) treated by iliosacral fixation alone using cannulated screws (Synthes, Oberdorf, Switzerland) in our institution between 12/2008 and 07/2010 were included in the present study. Fracture Injury, Int. J. Care Injured 42 (2011) 992–996 ARTICLE INFO Article history: Accepted 5 April 2011 Keywords: Percutaneous iliosacral screw fixation Rotationally unstable pelvic fracture Pelvic ring injuries ABSTRACT Objective: Although the stability of the pelvic ring primarily depends on the integrity of the posterior sacroiliac arch, lateral compression fractures with rotational instability are commonly treated by anterior fixation alone. The objective of the present study was to assess the outcome of patients with these fractures treated by posterior iliosacral screw fixation alone. Methods: Patients with rotationally unstable lateral compression fractures of the pelvic ring (Young and Burgess LC I and LC II or AO/Tile B2) treated by percutaneous iliosacral fixation alone were included. Postoperative complications, need for secondary surgery, malunion, secondary fracture displacement and the time to full-weight bearing were documented. Results: Twenty-five patients (13 female, 26 male; age: 56 Æ 20 years) were treated by percutaneous screw fixation (14 bilaterally, 11 unilaterally). Mean follow-up was 6 Æ 4 months, mean time to full weight bearing 9 Æ 3 weeks. Revision surgery was necessary in two patients (8%) due to nerve irritation; an additional anterior stabilisation was needed in two other patients (8%) due to secondary dislocation. Wound infection or motor weakness were not encountered, non-union of the posterior arch did not occur. Non-union of the pubic rami, however, occurred in two patients. The presence of malunion of the pubic rami did not affect the time to full weight bearing. Conclusions: Percutanous iliosacral screw fixation alone is a sufficient technique for the stabilisation of rotationally unstable pelvic fractures with low rates of complications or non-unions. It allows for a minimally invasive treatment thus being a useful option in patients who do not qualify for open anterior fixation. ß 2011 Elsevier Ltd. All rights reserved. * Corresponding author. Tel.: +41 44 255 1111; fax: +41 44 255 4406. E-mail address: georg.osterhoff@usz.ch (G. Osterhoff). Contents lists available at ScienceDirect Injury journal homepage: www.elsevier.com/locate/injury 0020–1383/$ – see front matter ß 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.injury.2011.04.005