nearly rigid ring comprising three elements: the sacrum and two paired lateral components, each composed of the
ilium, ischium, and pubis
individual bones are held together by tough but flexible ligaments
intact pelvis possesses an exceptional degree of strength
great forces are required to fracture the pelvis
Mechanism of Injury
motor vehicle collisions are responsible for 50% to 80% of pelvic fractures
motor vehicle versus pedestrian accounts for 10% to 30%
falls, motorcycle accidents, and crush injuries account for the rest
injury patterns result from the direction of the applied force
Anteroposterior Compression
caused by auto-pedestrian accidents or a direct crush injury to the pelvis
can result in disruption of the pubic symphysis and the anterior and posterior
sacroiliac ligaments
pelvis opens like a ‘book’, increasing intrapelvic volume
may be associated with urethral injury, bladder rupture, and damage to the pelvic blood
vessels
'Open-Book' Pelvic Fracture
Lateral Compression
can result in horizontal fractures of the pubic rami, compression fractures of the sacrum,
or fractures of the iliac wings
pelvic volume is compressed, so significant bleeding is not common
associated with a higher incidence of head injury compared with other types of pelvic fractures
Superior and Inferior Pubic Rami Fractures
Vertical Shear
results from axial loading in which the force is transmitted directly up one leg, often from a fall
produces vertically oriented fractures of the pubic rami, sacrum, and iliac wings
since the sacrospinous and sacrotuberous ligaments are disrupted, this injury is very unstable
damage to the sciatic nerve is frequent
often results in massive hemorrhage
Vertical Shear Pelvic Fracture
Combined Mechanism
involves two of the above mechanisms
associated with a high morbidity and mortality
Stable Fractures
stable fractures include nondisplaced fractures of the pelvic
ring, pubic rami fractures with less than 2.5 cm of displacement, or pubic symphysis
displacement less than 2.5 cm
rotational instability is characterized by greater than 2.5 cm widening of the pubic symphysis or greater
than 2.5 cm displacement of pubic rami fractures
vertical instability is characterized by greater than 1 cm superior translation of the hemipelvis
(requires disruption of the posterior sacroiliac ligaments)
Patient Evaluation
Physical Exam
leg-length discrepancy and external rotation suggests a pelvic fracture
pelvis may be assessed for stability and pain by administering A-P and lateral compression
digital rectal and vaginal examinations are necessary to assess for blood, lacerations, and
bony fragments
in men, a high-riding prostate suggests urethral disruption
in men, blood at the meatus mandates a retrograde urethrogram prior to inserting a Foley catheter
Radiology
initial study is the A-P pelvis film
CT of the pelvic bones is valuable to the orthopedic surgeon for planning operative fixation
of the fracture
additional x-rays and CT scans should only be done after all life-threatening injuries have been
corrected and the patient is hemodynamically stable
Management
consists of 3 objectives: 1) control of hemorrhage, 2) identification and management of associated injuries,
and 3) repair of the fracture
Control of Hemorrhage
hemodynamically unstable patients with a pelvic fracture are more likely to be bleeding from a nonpelvic
site than bleeding into the pelvis
chest x-ray is necessary to rule out a major hemothorax
abdomen should be assessed by FAST or DPL
DPL should be done in the supraumbilical position to avoid entering a pelvic hematoma
Control of Pelvic Hemorrhage
although any pelvic fracture can cause significant hemorrhage, most life-threatening blood
loss results from open book or vertical shear fractures, which cause massive venous bleeding
methods to control blood loss include reducing pelvic volume or angiographic embolization
Pneumatic Antishock Garment (PASG)
may be applied in the field by paramedics
blocks access to the patient and reduces diaphragmatic excursion
External Binders
can be fashioned out of a sheet wrapped around the pelvis
many commercial products exist
goal is to reduce the pelvic volume and tamponade bleeding
External Fixation
anterior external fixators may have value in patients with anterior instability (diastasis of the symphysis pubis)
but they will not control bleeding from the disrupted sacroiliac venous plexus
the pelvic C-clamp device has been used to provide emergent posterior stabilization and may be more effective
in controlling venous hemorrhage
Angiography
only 10% of pelvic hemorrhage is from an arterial source, but bleeding vessels may be embolized
in practice, both skeletal fixation and angiography may both be necessary to control blood loss
Pelvic Packing
lower midline incision
stay extraperitoneal
3 laparotomy pads are placed on each side of the bladder
Preperitoneal Pelvic Packing (image from The American College of Surgeons)
Associated Injuries
Bladder Injury
occurs in 7% to 15% of pelvic fractures
results from a burst injury
most patients have hematuria
diagnosis is made by cystography or CT scan
most are retroperitoneal and are adequately treated with a Foley catheter for 7 to 10 days
intraperitoneal perforations require laparotomy for closure
Urethral Injury
occurs in 5% to 12% of males with pelvic fractures
should be suspected if there is blood at the meatus or scrotal ecchymosis
pubic diastasis or inferior pubic rami fractures (straddle fractures) greatly increase the odds
of urethral injury
rectal exam may reveal a high-riding prostate
retrograde cystogram should demonstrate the urethral tear
treatment consists of placement of a suprapubic catheter, with a delayed repair of the urethra
Rectal Injury
if blood is in the rectal vault, or bony fragments are felt on rectal exam, proctoscopy should be performed
treatment consists of a diverting colostomy, presacral drainage, and possibly washout of the rectal vault to minimize
contamination of the fracture and its associated hematoma
Vaginal Injury
identified by the presence of blood or bony fragments in the vagina
vaginal lacerations should be closed primarily once the life-threatening problems have been addressed
in the absence of a perineal wound, a colostomy is not necessary
Nerve Injury
sciatic nerve is the nerve most frequently injured
obturator and femoral nerves are injured less frequently
Repair of the Pelvic Fracture
Stable Fractures
treated with pain control and early mobilization with protected weight bearing
Unstable Fractures
unstable fractures will require ORIF
Complications of Pelvic Fractures
Venous Thromboembolism
risk of DVT, without prophylaxis, ranges from 30% to 60%; and with prophylaxis, from 5% to 15%
incidence of pulmonary embolism ranges from 1% to 9%
Long Term Complications
low back pain, limb-length discrepancies, urinary incontinence, impotence, difficulty with childbearing
