Review Question - QID 3030

Figures A through D show a comminuted both column acetabular fracture. In this injury, both columns are involved, with the acetabulum losing all connection to the axial skeleton (sacrum). This differentiates it from all other patterns, where at least part of the acetabular cartilage maintains connection to the sacrum.

Figure C shows the ischial spur, which is classically known as the spur sign and most easily seen on the obturator oblique radiograph.

Incorrect Answers:
Answer 1: This injury has axial skeleton attachment to the acetabular cartilage through the posterior column.
Answer 3: This injury has axial skeleton attachment to the acetabular cartilage through the anterior and posterior columns.
Answer 4: This injury has axial skeleton attachment to the acetabular cartilage through the anterior column as well as the posterior column, depending on fracture pattern.
Answer 5: This injury has no posterior column involvement, and therefore the posterior column maintains the axial skeleton attachment to the acetabulum.