- Discussion:
- its the most common pelvic fracture pattern;
- involves compression
injury to sacrum, w/ cancellous impaction;
- sacral injury is often not identified & frx pattern is often misidentified
as isolated
pubic ramus frx;
- sacral compression frxs are usually stable since cancellous bone
of sacrum is impacted;
- Radiographs:
-
sacral impaction frx are best noted by observing borders of sacral foramina for
discontinuity on
inlet view;
- discontinuity identifies the injury as an LC type;
- AO Type B2.1
- lateral compressive force applied to the hemipelvis, crushes
SI complex
& causes anterior injury on the same side;
- anterior injury may involve frx of both superior & inferior pubic rami which may be overriding;
- posterior injury is a compression fracture of anterior of anterior aspect of the sacrum;
- intact tension band of the pelvis as well as an intact pelvic floor do not allow vertical
displacement in this injury type;
- it has internal rotational instability but is vertically stable;
