Open book fracture of the pelvis

CLINICAL DATA: Pelvic pain following trauma.

X-RAY:

• disruption of pubis symphysis.
• the pelvis opens like a book.
• sacroilial joint disruption.

CT STUDY:

• sacroiliac joint diastasis bilaterally. Contrast in the ureters in this delayed phase.

• symphyseal and sacroiliac joint diastasis.
• Fracture of left lateral edge of the lower sacruum.

DISCUSSION:

1. a pelvic fracture due to anteroposterior compression injury to the pelvis.
2. know as Malgaigne fracture — disruption of the joints of the symphysis pubis and sacroiliac joint from complete ligamentous injury
3. X-ray anteroposterior pelvic radiograph is the basic screening test and uncovers 90% of pelvic injuries.
4. CT scan is the best imaging study for evaluation of pelvic anatomy and degree of pelvic, retroperitoneal, and intraperitoneal bleeding. CT scan also confirms hip dislocation associated with an acetabular fracture.
5. Unstable pelvic fractures:

• anteroposterior compression resulting in open book or sprung pelvis fractures.
• lateral compression resulting in windswept pelvis.
• vertical shear resulting in Malgaigne fracture or bucket hande fracture.
• combined mechanical: happen when two different force vectors are involved and results in a complex fracture pattern.
• More than 5 mm to 15 mm of cephalic displacement of the posterior SI complex on outlet views implies instability.

Associated injuries:

• significant risk of uncontrolled pelvic bleeding and exsanguination from pelvic fractures resulting in pelvic, thigh and/or retroperitoneal haemorrhage. The most frequently injured arteries are parietal branch of the commune, internal or external arteries because of their proximity to the bone, the sacro-iliac joint and the inferior ligaments of the pelvis. 
• bladder rupture.
• urethral injury.
• The pelvic bone dislocation and the increase of pelvic volume facilitate blood effusion.