The role of anterior supra-acetabular external fixator as definitive treatment for anterior ring fixation in unstable pelvic fractures



Management of anterior ring injuries is still a matter of discussion, and there are only few studies reporting anterior external fixator as definitive treatment for unstable pelvic injuries. This study aimed to describe the clinical and radiological outcomes of a consecutive series of mechanically unstable pelvic injuries that were treated with definitive anterior supra-acetabular external fixator for the anterior ring, and to identify risk factors for failure.


We included a consecutive series of patients with unstable pelvic ring fractures who underwent anterior supra-acetabular external fixation for definitive treatment, between January 2012 and January 2020. All demographics, associated injuries and procedures, injury mechanism, and complications were analysed. Pelvic fracture was classified based on Orthopaedic Trauma Association/Tile AO (OTA/AO) and Young–Burgess classifications. Complications associated with the external fixator were revised. All patients were functionally evaluated at final follow-up and asked to report their clinical outcomes using the Majeed score.


A total of 47 patients were included, of which 25 were females. The median age was 44 years (interquartile range 23–59). Median follow-up duration was 14 months (interquartile range 6–31). The most frequent aetiology was motor vehicle accident (35), followed by fall from height (8). All fractures required posterior pelvic ring fixation. The median time during which patients had external fixation in situ was 11 weeks (interquartile range 9–13). All patients achieved healing of pelvic fracture at median time of 10 weeks (interquartile range 8–12). At final follow-up, the median displacement of the anterior pelvis was 6 mm (interquartile range 0–11). Superficial infection was the most common complication (n = 7). No washout procedures were needed. No major complication was reported. No patient required reoperation for anterior ring fracture. The median Majeed score was 88 points (range 60–95; interquartile range 80–90) at final follow-up.


Our findings suggest that the use of supra-acetabular external fixator is safe and effective for definitive treatment of the anterior ring in unstable pelvic fractures. It is a method with high proportion of excellent results, regardless of the type of fracture. The rate of complications is low, and it does not compromise functional results.

This is a preview of subscription content, access via your institution.

Fig. 1:
Fig. 2:
Fig. 3


  1. 1.

    Wojahn RD, Gardner MJ. Fixation of anterior pelvic ring injuries. J Am Acad Orthop Surg. 2019;27:667–76.

    Article  PubMed  Google Scholar 

  2. 2.

    Marecek GS, Scolaro JA. Anterior pelvic ring: introduction to evaluation and management. J Orthop Trauma. 2018;32:8–10.

    Article  Google Scholar 

  3. 3.

    Kleweno CP, Scolaro J, Sciadini MF, McAlister I, Shannon SF, Chip Routt ML. Management of pelvic fractures. Instr Course Lect. 2020;69:489–506.

    PubMed  Google Scholar 

  4. 4.

    Gill JR, Murphy C, Quansah B, Carrothers A. Management of the open book APC II pelvis: survey results from pelvic and acetabular surgeons in the United Kingdom. J Orthop. 2017;14:530–6.

    Article  PubMed  PubMed Central  Google Scholar 

  5. 5.

    Sagi HC, Papp S. Comparative radiographic and clinical outcome of two-hole and multi-hole symphyseal plating. J Orthop Trauma. 2008;22:373–8.

    Article  PubMed  Google Scholar 

  6. 6.

    Song W, Zhou D, He Y. Biomechanical characteristics of fixation methods for floating pubic symphysis. J Orthop Surg Res. 2017;12:10–6.

    Article  Google Scholar 

  7. 7.

    Griffin DR, Starr AJ, Reinert CM, Jones AL, Whitlock S. Vertically unstable pelvic fractures fixed with percutaneous iliosacral screws: does posterior injury pattern predict fixation failure? J Orthop Trauma. 2003;17:399–405.

    Article  PubMed  Google Scholar 

  8. 8.

    Solomon LB, Pohl AP, Sukthankar A, Chehade MJ. The subcristal pelvic external fixator: technique, results, and rationale. J Orthop Trauma. 2009;23:365–9.

    Article  PubMed  Google Scholar 

  9. 9.

    Starr AJ, Nakatani T, Reinert CM, Cederberg K. Superior pubic ramus fractures fixed with percutaneous screws: what predicts fixation failure? J Orthop Trauma. 2008;22:81–7.

    Article  PubMed  Google Scholar 

  10. 10.

    Feng Y, Hong J, Guo X, Lin C, Ling W, Zhang L, et al. Percutaneous fixation of traumatic pubic symphysis diastasis using a TightRope and external fixator versus using a cannulated screw. J Orthop Surg Res. 2016;11:1–7.

    Article  Google Scholar 

  11. 11.

    Eastman JG, Krieg JC, Routt MLC. Early failure of symphysis pubis plating. Injury. 2016;47:1707–12.

    Article  PubMed  Google Scholar 

  12. 12.

    Collinge C, Archdeacon MT, Dulaney-Cripe E, Moed BR. Radiographic changes of implant failure after plating for pubic symphysis diastasis: an underappreciated reality? Clin Orthop Relat Res. 2012;470:2148–53.

    Article  PubMed  PubMed Central  Google Scholar 

  13. 13.

    Moed BR, Grimshaw CS, Segina DN. Failure of locked design-specific plate fixation of the pubic symphysis: a report of six cases. J Orthop Trauma. 2012;26:e71–5.

    Article  PubMed  Google Scholar 

  14. 14.

    Morris SAC, Loveridge J, Smart DKA, Ward AJ, Chesser TJS. Is fixation failure after plate fixation of the symphysis pubis clinically important? Clin Orthop Relat Res. 2012;470:2154–60.

    Article  PubMed  PubMed Central  Google Scholar 

  15. 15.

    Hoyt BW, Lundy AE, Purcell RL, Harrington CJ, Gordon WT. Definitive external fixation for anterior stabilization of combat-related pelvic ring injuries, with or without sacroiliac fixation. Clin Orthop Relat Res. 2020;478:779–89.

    Article  PubMed  Google Scholar 

  16. 16.

    Lee C, Sciadini M. The use of external fixation for the management of the unstable anterior pelvic ring. J Orthop Trauma. 2018;32:S14–7.

    Article  PubMed  Google Scholar 

  17. 17.

    Bellabarba C, Ricci WM, Bolhofner BR. Distraction external fixation in lateral compression pelvic fractures. J Orthop Trauma. 2000;14:475–82.

    CAS  Article  PubMed  Google Scholar 

  18. 18.

    Gänsslen A, Pohlemann T, Krettek C. Supraacetabular external fixation for pelvic ring fractures. Eur J Trauma. 2006;32:489–99.

    Article  Google Scholar 

  19. 19.

    Noordeen MHH, Taylor BA, Briggs TWR, Lavy CBD. Pin placement in pelvic external fixation. Injury. 1993;24:581–4.

    CAS  Article  PubMed  Google Scholar 

  20. 20.

    Haidukewych GJ, Kumar S, Prpa B. Placement of half-pins for supra-acetabular external fixation: an anatomic study. Clin Orthop Relat Res. 2003;411:269–73.

    Article  Google Scholar 

  21. 21.

    Lidder S, Heidari N, Gänsslen A, Grechenig W. Radiological landmarks for the safe extra-capsular placement of supra-acetabular half pins for external fixation. Surg Radiol Anat. 2013;35:131–5.

    Article  PubMed  Google Scholar 

  22. 22.

    McDonald C, Firoozabadi R, Routt ML, Kleweno C. Complications associated with pelvic external fixation. Orthopedics. 2017;40:e959–63.

    Article  PubMed  Google Scholar 

  23. 23.

    Scaglione M, Parchi P, Digrandi G, Latessa M, Guido G. External fixation in pelvic fractures. Musculoskelet Surg. 2010;94:63–70.

    Article  PubMed  Google Scholar 

  24. 24.

    Mitchell PM, Corrigan CM, Patel NA, Silverberg AJ, Greenberg SE, Thakore RV, et al. 13-year experience in external fixation of the pelvis: complications, reduction and removal. Eur J Trauma Emerg Surg. 2016;42:91–6.

    CAS  Article  PubMed  Google Scholar 

  25. 25.

    Guimarães RP, de Góes RA, Ulson O, de Ávila RB, Ono NK, Polesello GC. Supra-acetabular fixation and sacroiliac screws for treating unstable pelvic ring injuries: preliminary results from 20 patients. Rev Bras Ortop (English Ed). 2016;51:132–7.

    Article  Google Scholar 

  26. 26.

    Majeed SA. Grading the outcome of pelvic fractures. J Bone Joint Surg Br. 1989;71:304–6.

    CAS  Article  PubMed  Google Scholar 

  27. 27.

    Lefaivre KA, Slobogean GP, Valeriote J, O’Brien PJ, Macadam SA. Reporting and interpretation of the functional outcomes after the surgical treatment of disruptions of the pelvic ring: a systematic review. J Bone Joint Surg Br. 2012;94:549–55.

    CAS  Article  PubMed  Google Scholar 

  28. 28.

    Meinberg EG, Agel J, Roberts CS, Karam MD, Kellam JF. Fracture and dislocation classification compendium-2018. J Orthop Trauma. 2018;32(Suppl 1):S1-170.

    Article  PubMed  Google Scholar 

  29. 29.

    Lefaivre KA, Slobogean G, Starr AJ, Guy P, O’Brien PJ, MacAdam SA. Methodology and interpretation of radiographic outcomes in surgically treated pelvic fractures: a systematic review. J Orthop Trauma. 2012;26:474–81.

    Article  PubMed  Google Scholar 

  30. 30.

    Gardner MJ, Nork SE. Stabilization of unstable pelvic fractures with supraacetabular compression external fixation. J Orthop Trauma. 2007;21:269–73.

    Article  PubMed  Google Scholar 

  31. 31.

    Sagi HC, Coniglione FM, Stanford JH. Examination under anesthetic for occult pelvic ring instability. J Orthop Trauma. 2011;25:529–36.

    Article  PubMed  Google Scholar 

  32. 32.

    Papakostidis C, Kanakaris NK, Kontakis G, Giannoudis PV. Pelvic ring disruptions: treatment modalities and analysis of outcomes. Int Orthop. 2009;33:329–38.

    CAS  Article  PubMed  Google Scholar 

  33. 33.

    Pizanis A, Garcia P, Santelmann M, Culemann U, Pohlemann T. Reduction and fixation capabilities of different plate designs for pubic symphysis disruption: a biomechanical comparison. Injury. 2013;44:183–8.

    Article  PubMed  Google Scholar 

  34. 34.

    Merriman DJ, Ricci WM, McAndrew CM, Gardner MJ. Is application of an internal anterior pelvic fixator anatomically feasible? Clin Orthop Relat Res. 2012;470:2111–5.

    Article  PubMed  PubMed Central  Google Scholar 

  35. 35.

    Vaidya R, Colen R, Vigdorchik J, Tonnos F, Sethi A. Treatment of unstable pelvic ring injuries with an internal anterior fixator and posterior fixation: initial clinical series. J Orthop Trauma. 2012;26:1–8.

    Article  PubMed  Google Scholar 

  36. 36.

    Yu KH, Hong JJ, Guo XS, Zhou DS. Comparison of reconstruction plate screw fixation and percutaneous cannulated screw fixation in treatment of Tile B1 type pubic symphysis diastasis: a finite element analysis and 10-year clinical experience. J Orthop Surg Res. 2015;10:1–8.

    Article  Google Scholar 

  37. 37.

    Wardle B, Eslick GD, Sunner P. Internal versus external fixation of the anterior component in unstable fractures of the pelvic ring: pooled results from a systematic review. Eur J Trauma Emerg Surg. 2016;42:635–43.

    CAS  Article  PubMed  Google Scholar 

  38. 38.

    Mason WTM, Khan SN, James CL, Chesser TJS, Ward AJ. Complications of temporary and definitive external fixation of pelvic ring injuries. Injury. 2005;36:599–604.

    CAS  Article  PubMed  Google Scholar 

  39. 39.

    Chiu FY, Chuang TY, Lo WH. Treatment of unstable pelvic fractures: use of a transiliac sacral rod for posterior lesions and an external fixator for anterior lesions. J Trauma Inj Infect Crit Care. 2004;57:141–4.

    Article  Google Scholar 

  40. 40.

    Lindahl J, Hirvensalo E, Böstman O, Santavirta S. Failure of reduction with an external fixator in the management of injuries of the pelvic ring. Long-term evaluation of 110 patients. J Bone Joint Surg Br. 1999;81:955–62.

    CAS  Article  PubMed  Google Scholar 

  41. 41.

    Kim WY, Hearn TC, Seleem O, Mahalingam E, Stephen D, Tile M. Effect of pin location on stability of pelvic external fixation. Clin Orthop Relat Res. 1999;361:237–44.

    Article  Google Scholar 

  42. 42.

    Stewart RG, Hammer N, Kieser DC. External fixation of unstable pelvic fractures: a systematic review and meta-analysis. ANZ J Surg. 2019;89:1022–7.

    Article  PubMed  Google Scholar 

  43. 43.

    Çavusoglu AT, Erbay FK, Özsoy MH, Demir T. Biomechanical comparison of supraacetabular external fixation and anterior pelvic bridge plating. Proc Inst Mech Eng H. 2017;231:931–7.

    Article  PubMed  Google Scholar 

  44. 44.

    Mcdonald E, Theologis AA, Horst P, Kandemir U, Pekmezci M. When do anterior external or internal fixators provide additional stability in an unstable (Tile C) pelvic fracture? A biomechanical study. Eur J Trauma Emerg Surg. 2015;41:665–71.

    CAS  Article  PubMed  Google Scholar 

  45. 45.

    Jordan MC, Brems AC, Heintel T, Jansen H, Hoelscher-Doht S, Meffert RH. The anterior subcutaneous pelvic ring fixator: no biomechanical advantages compared with external fixation. J Bone Joint Surg Am. 2019;101:1724–31.

    Article  PubMed  Google Scholar 

  46. 46.

    MacCormick LM, Chen F, Gilbertson J, Khan S, Schroder LK, Bechtold JE, Cole PA. A biomechanical study comparing minimally invasive anterior pelvic ring fixation techniques to external fixation. Injury. 2018;50(2):251–5.

    Article  PubMed  Google Scholar 

  47. 47.

    Stuby FM, Doebele S, Agarwal Y, Windolf M, Gueorguiev B, Ochs BG. Influence of flexible fixation for open book injury after pelvic trauma—a biomechanical study. Clin Biomech. 2014;29:657–63.

    Article  Google Scholar 

  48. 48.

    Ohmori T, Kitamura T, Nishida T, Matsumoto T, Tokioka T. The impact of external fixation on mortality in patients with an unstable pelvic ring fracture: a propensity-matched cohort study. Bone Joint J. 2018;100B:233–41.

    Article  Google Scholar 

  49. 49.

    Tosounidis TH, Sheikh HQ, Kanakaris NK, Giannoudis PV. The use of external fixators in the definitive stabilisation of the pelvis in polytrauma patients: safety, efficacy and clinical outcomes. Injury. 2017;48:1139–46.

    Article  PubMed  Google Scholar 

  50. 50.

    Lybrand K, Bell A, Rodericks D, Templeman D, Tornetta P. APC injuries with symphyseal fixation: what affects outcome? J Orthop Trauma. 2017;31:27–30.

    Article  PubMed  Google Scholar 

  51. 51.

    Stuby FM, Lenz M, Doebele S, et al. Symphyseal fixation in open book injuries cannot fully compensate anterior SI joint injury—a biomechanical study in a two-leg alternating load model. PLoS ONE. 2017;12:1–11.

    CAS  Article  Google Scholar 

  52. 52.

    Sellei RM, Schandelmaier P, Kobbe P, Knobe M, Pape HC. Can a modified anterior external fixator provide posterior compression of AP compression type III pelvic injuries? Clin Orthop Relat Res. 2013;471:2862–8.

    Article  PubMed  PubMed Central  Google Scholar 

  53. 53.

    Ponson KJ, van Dijke GAH, Joosse P, Snijders CJ. Improvement of external fixator performance in type C pelvic ring injuries by plating of the pubic symphysis: an experimental study on 12 external fixators. J Trauma. 2002;53:907–13.

    CAS  Article  PubMed  Google Scholar 

  54. 54.

    Gardner MJ, Kendoff D, Ostermeier S, Citak M, Hüfner T, Krettek C, et al. Sacroiliac joint compression using an anterior pelvic compressor: a mechanical study in synthetic bone. J Orthop Trauma. 2007;21:435–41.

    Article  PubMed  Google Scholar 

Download references


No funding was received for this study.

Author information



Corresponding author

Correspondence to Cristián Barrientos-Mendoza.

Ethics declarations

Conflict of interest

The authors declares that they have no conflict of interest.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Barrientos-Mendoza, C., Brañes, J., Wulf, R. et al. The role of anterior supra-acetabular external fixator as definitive treatment for anterior ring fixation in unstable pelvic fractures. Eur J Trauma Emerg Surg (2021).

Download citation


  • Unstable pelvic ring injuries
  • Anterior ring pelvic fractures
  • Definitive stabilisation
  • Supra-acetabular external fixation
  • Ex fix
  • External fixation
  • Pelvic fracture