Similar patient reported outcomes at long-term follow-up after external fixation versus internal fixation of the anterior ring component of APC injuries.

Purpose: Unstable pelvic ring injuries produced by external rotation of the hemipelvis and a symphyseal disruption are most often treated with internal fixation of the anterior ring, with percutaneous treatment of the posterior ring as needed. In some clinical situations, patients are treated with external fixation for their anterior injuries and the long-term functional outcomes associated with external fixation are not well understood. We ask if there is a difference in functional outcome, between treatment of these injuries with internal versus external fixation, when measured at a minimum of three years after injury.

Method: This was a retrospective cohort study performed at a level one regional trauma center. Trauma database review identified 128 patients, with 70 subsequently excluded, with unstable anterior posterior compression (APC) pelvic ring injuries (OTA 61B2.3 & 61C1.2) treated with surgery with minimum three years of follow-up. An intervention of internal fixation versus external fixation of anterior pelvic ring was performed, and depending on the injury, supplemented with posterior iliosacral screw fixation. Main outcome was measured with the Majeed functional outcome score (0-100).

Results: Patients treated with external fixation reported a Majeed score of 70 (95% CI 28-100) compared to 79 (95% CI 36-100) in those with internal fixation (p-value 0.28). Subgroups of the Majeed score were not significantly different (p value > 0.05). Open fractures, severity of injury, and ISS were worse in those treated with external fixation. There was no differential loss to follow-up. Conclusion Patients with unstable pelvic ring injuries with symphyseal disruptions treated with external fixation as definitive treatment versus internal fixation may fare no different in the long term.