55 - Pelvic Trauma

List the five ligaments that maintain the integrity of the posterior arch

• Sacrospinous • Sacrotuberous • Iliolumbar • Anterior SI • Posterior SI

List XR findings associated with bladder rupture (3)

• Anterior arch fracture with • Diastasis of symphysis > 1 cm • Fracture around obturator ring > 1 cm displaced

List three bony injuries associated with vertical shear fractures

• Avulsion ischial spine • Avulsion lower lateral lip of the sacrum • Avulsion of the transverse process of L5

Describe an "open book" pelvis

• Diastasis of public symphysis > 2.5 cm • Means there is disruption of the anterior (+/- posterior) ligaments • From AP compression, often associated with vertical shear as well (if involves posterior ligaments)

Describe a straddle fracture

• Four-pillar injury • Bilateral pubic rami # ("butterfly segment") • Commonly associated with lateral compression or vertical shear forces causing injury to the posterior pelvic arch • Frequently associated injuries of GU tract

Describe the three types of vertical sacral fractures (?Denis classification)

• Fracture lateral to sacral foramina (sacral foramina = sacral ala) • Fracture through sacral foramina • Fracture medial to sacral foramina (involving central spinal canal) • *Remember vertical sacral fractures (as opposed to transverse) involve the pelvic ring • High risk neurologic compromise (medial > through > lateral)

What is a Malgaine fracture?

• Fracture of the ilium near the SI joint with displacement of the symphysis OR a dislocation of the SI joint with fracture of both ipsilateral pelvic rami • Associated with urethral injury

List two pelvic fracture associated with urethral injury

• Malgagine • Straddle injury (butterfly)

Describe the typical "dashboard" injury pattern to the lower limb (4)

• Posterior hip dislocation • Posterior acetabular fracture • Sciatic nerve injury • Patella fracture +/- dislocation

Describe the normal pubic symphysis (+ relationship to pubic rami) and SI joint distances

• Pubic symphysis < 5mm • Pregnancy pubic symphysis < 8mm • Small 1 - 2 mm vertical offset of the left and right pubic rami • NO overlapping of pubic symphysis • SI joint 2 - 4 mm wide

Describe the relationship between level and neurologic findings with transverse sacral fractures

• Rare at S4 and below • Common above S4

BOX 55-4: List goals of management of pelvic fractures

• Resuscitation: transfuse for hemorrhagic shock • Recognition: posterior arch = higher risk hemorrhage • Evaluation: identify serious accompanying injuries • Stabilization: bind pelvis then definitive ortho fixation • Control pelvic bleeding: angiography vs pelvic packing

List the three mechanisms of pelvic fracture by their level of need for blood transfusions

AP compression > vertical shear > lateral compression

What exam physical exam maneuver do patients with pelvic fracture need?

DRE and vaginal exam to r/o open pelvic #