vertical shear

Definition

Unstable injuries

Complete disruption of both the anterior and posterior ring

5 - 20% of pelvic fractures

Mechanism

Axial load

Motor vehicle accident

Fall from height

Pathology

Anterior ring

LC-1:  pubic rami fracture with sacral fracture

Anatomy

Pelvis is a true ring

- any anterior fracture must have a posterior injury as well

- integrity of the posterior sacroiliac complex is key

Bony Anatomy

2 innominate bones + sacrum

Symphysis pubis < 5mm

SI joint 2-4 mm