In this communication we characterize and name an earlier undefined type of acetabular fracture—the acetabular greenstick fracture. This is a subtype of fracture in which the anterior column component is incomplete, that is, the anterior column is fractured only in its inferior part (iliac body), whereas its superior part (the iliac crest) is intact. These fractures are characterized by an external rotation of the anterior acetabular dome on the axis of the intact iliac crest. The intact iliac crest might prevent anatomic reduction. Iliac crest osteotomy is proposed as a novel surgical technique to assist reducing this type of fractures. The fracture type and surgical techniques are shown by an illustrative case.