What are the risk factors for complications after combined injury of the pelvic ring and acetabulum?

PURPOSE: Combined acetabular and pelvic ring injuries represent a unique subset of pelvic trauma and little is known regarding their complications and outcomes. We sought to further evaluate these injury patterns and quantify their outcomes. METHODS: A retrospective review at a single level 1 trauma center was performed on all patients with operatively treated combined ring and acetabulum injuries during a seven-year period. Main outcome measurements include all-cause complication including residual neurologic deficit, deep infection, conversion to total hip arthroplasty, deep venous thrombosis and mortality. RESULTS: Seventy operatively treated combined ring and acetabulum patients with one-year follow-up were reviewed. The overall complication rate was 44%. Hip dislocation occurred in 40% of the cohort and was significantly associated with residual neurologic deficit and all-cause complication. Angiography with embolization was not associated with an increased rate of deep infection. Open acetabular approaches had a significantly higher complication rate compared to percutaneous procedures. Delay to definitive fixation greater than 36 h trended toward but did not reach association with all complications. CONCLUSION: Combined injuries to the acetabulum and pelvic ring have high rates of complications. No individual fracture patterns were identified as risk factors, but hip dislocation was associated with an increased rate of complications. When possible, percutaneous reduction and fixation of acetabular fractures and early definitive fracture fixation lead to lower rates of complications. Use of angiography with embolization appears to be safe and does not increase the risk of infection or other complications.