(iii) Principles of acetabular fractures

Acetabular fractures are rare, significant injuries involving the articular surface of the acetabulum. They are typically associated with a high-energy mechanism of injury, though fragility type fractures are now increasingly seen. Associated injuries to another organ system are seen in half of all cases. Radiographic assessment is performed using antero-posterior pelvic radiographs and Judet views, as well as computerized tomography (CT). Classification is based on the column theory and describes fracture anatomy in relation to the anterior and posterior columns. Non-operative treatment is indicated when there is less than 2 mm of articular displacement or when patient factors (such as associated injuries/co-morbidities) or soft tissue injury are incompatible with surgery. Open reduction and internal fixation is indicated in displaced fractures, total hip arthroplasty being used in unreconstructable injuries. Operative treatment involves difficult exposures and technically demanding reduction and fixation techniques. Significant associated injuries include neurovascular injury, bleeding, open fracture wounds, soft tissue injury, hip dislocation and femoral fractures. Late complications include post-traumatic osteoarthritis, avascular necrosis and heterotopic ossification. The goals of treatment should be to give the patient a congruent, functional hip whilst minimizing the complications from both the injury and surgery. Poor results are more likely if the reduction is non-anatomical.