Pelvic Injuries

by Sercan Yalcinli

Introduction

Pelvic fractures constitute 1-3% of pelvic skeletal fractures. In younger adults, a pelvic fracture is generally due to high energy pelvic injuries secondary to motor vehicle injuries, pedestrian injuries, falls from height, motorcycle accidents and crush injuries. In the elderly, it may occur following a fall from a sitting position. Pelvic trauma-related mortality is between 3-20%. It reaches 40-50% in hemodynamically unstable patients.

The pelvis is composed of three bones: Two innominate bones and sacrum. İlium, ischium and pubis bones form the innominate. (See figures 1,2,3)

Figure 1. Anterior view of pelvic bones

Figure 2. Superior view of pelvic bones

Figure 3. Posterior view of pelvic bones

The posterior sacroiliac, sacrotuberous and sacrospinous ligaments located between the sacrum and two innominate bones provide the pelvic stability. Symphysis pubis supports pelvis frontally. (See figure 4)

Figure 4. Pelvic ligaments

Three bones form the acetabulum. The ilium forms the upper boundary; ischium forms the posterior part and ilium and pubis form the anterior part of the acetabulum. (See figure-5)

Figure 5. Acetabulum anathomy

The pelvis has a complex vasculature. Iliac arteries and main veins are close to both sides of the sacroiliac joints. (See figure 6) The thin-walled venous structures have limited contraction capabilities. Therefore, patients with pelvic fractures may have life-threatening bleedings.

Figure 6. Pelvic vessels

Cauda equina courses through the sacral spinal cord and leaves at the sacral spinal foramina to form the lumbar and sacral plexus. Lumbosacral plexus is the thickest peripheral nerve of the body and is frequently injured in posterior hip dislocation with acetabular fracture. Watch this video for detailed information.

Pelvic fractures are divided into three groups:

a) pelvic fractures which cause separation of pelvic ring,

b) no separation of pelvic ring with one bone fracture (see figure 7) and

c) acetabular fractures.

Figure 7. Nondisplacement fractures of pelvis
a: fracture on iliac crest/ilium, b: fracture of superior pubic ramus, c: fracture of ischium, d: fracture of anterior superior iliac spine, e: fracture of anterior inferior iliac spine, g: fracture of sacrum, H: fracture of coccyx.

Acetabular fractures are often associated with the femur fracture, hip fracture and dislocations, and knee injuries. Posterior wall fracture is the most common acetabular injury and is usually associated with posterior dislocation of the hip. Posterior hip dislocation is generally associated with sciatic nerve injury. Watch this video for detailed information. (See image 1, 2, 3 )

Image 1. Posterior acetabular fracture associated with posterior dislocation of the right hip

Image 2. Iliac and anterior column fracture of acetabulum.

Image 3. Iliac and anterior column fracture of acetabulum. 3D reconstruction in the CT of of the patient with image 2..

Several classifications are used to identify pelvic fractures (see video)

Young-Burgess Classification classifies fractures according to the direction of the force that caused the injury and the mechanisms of injury . There are four different fracture models according to this classification system:

• lateral compression (LC),
• anteroposterior compression (AP),
• vertical scissor (VS) and
• combined mechanisms.

Lateral compression is the most common mechanism. It corresponds to 50% of the injuries. An example is a side impact of a motor vehicle to a pedestrian (see figure 8, image 4).

 

Figure 8. Lateral compression fractures of pelvis. Left to right. Type 1, Type 2, and Type 3. Type 1 includes sacral compression fracture on ipsilateral side. Type 2 is a sacral injury with disruption of posterior sacroiliac ligaments. Iliac wing fracture on impaction side can be seen. Type 3 includes Type 1 and 2 injuries on impaction side with open book fracture/injury on contralateral side.

Image 4. Lateral compression type 3 injury; inferior and superior pubic rami fractures on impaction side and contralateral sacroiliac widening

AP compression or open book injury is the second most common mechanism and corresponds to 25% of injuries. An example is a frontal impact of the motor vehicle. (See figure 9) (See image 5, 6)

Figure 9. Anteroposterior compression fractures of pelvis. Left to right Type 1, 2, and 3. Type 1: symphysis pubis diastasis less than 2.5 cm, ligaments are stretched (anterior sacroiliac, sacra-tuberous, sacrospinous) but intact. Type 2: Symphysis separated more than 2.5 cm. ligaments (sacra-tuberous, sacrospinous) are disrupted. Sacroiliac ligaments are intact. Type 3: Symphysis separated more than 2.5 cm and all ligaments are disrupted.

 

Image 5. Antero-posterior compression type 2 injury with right femur bone fracture

Image 6. Type 3 injury

The least common is VS as it generates 5% of the injuries. Falls from heights are examples. (See figure 10, image 7)

Figure 10. Vertical compression injury. Pubis and sacroiliac joints are disrupted.

 

Image 7. Left iliac wing, acetabulum and inferior pubis fracture of pelvis

Coexistence of other injuries constitutes 20-25% of injuries.

Tile classification is about the mechanical stability of the pelvis.

Type A – Stable pelvic ring injuries, posterior stability is intact: Avulsion fractures, isolated iliac wing fractures, isolated pubic rami fractures, transverse fractures of sacrum or coccyx.

Type B – Partially stable pelvic ring injury (incomplete disruption of the posterior pelvis) rotationally unstable, vertically stable: Open-book fractures, lateral compression fractures, double rami fractures and posterior injury

Type C – Unstable pelvic ring injury: Vertical shearing fractures, rotationally and vertically unstable.

Tile classification system predicts the need for surgical intervention. Young and Burgess determines the pattern of the fracture and predicts the chance of associated injuries and mortality risk.

Case Presentation

A 38-year-old male presents to the emergency department following a motor vehicle accident. The patient has left femoral and hip pain. His vitals are as follows: Blood pressure 100/60 mmHg, heart rate 108 beats per minute, pulse oxygen saturation at room air 99%. His physical examination reveals suprapubic tenderness, limitation of motion in the left hip joint, pelvic tenderness and hemorrhage at urethral meatus. Point-of-care ultrasonography shows no intraabdominal free fluid. Plain pelvic radiography and retrograde urethrography show superior pubic ramus fracture, sacral fracture, 3 cm displacement of the symphysis pubis, left femur bone fracture and urethral injury, respectively. Computerized tomography confirms retroperitoneal hemorrhage. The patient is brought to the operating room.

Critical Bedside Actions and General Approach

• In multi-trauma patient, start with general trauma care including ABC.
• Mechanical stabilization and immobilization of the patient are important because they reduce the risk of bleeding and secondary organ injuries.
• Consider other organ injuries, especially with unstable pelvic fractures (e.g., intraabdominal injuries, gastrointestinal tract injuries, genitourinary injuries, major vascular injuries, and neurological injuries)
  • Check vital signs
  • Physical examination
  • Take medical history
  • Learn mechanism of injury
  • Ensure an iv line (except lower extremity)
  • Type and crossmatch
  • Order necessary imaging, labs, etc..
  • Determine the need for operation and type of pelvic fracture, stable or unstable (mechanically and hemodynamically).

Differential Diagnoses

• Abdominal pain in elderly
• Blunt abdominal trauma
• Hip dislocation
• Hip fracture

History And Physical Examination Hints

The mechanism of injury plays a vital role in identifying pelvic fracture risk and determining the severity of the fracture. Low-energy injuries (such as falling on the ground) typically lead to a stable injury. High-energy injuries (such as motor vehicle accidents) increase the risk of unstable pelvic fractures and other organ injuries.

The direction of the force may give an idea about the type of injury. Antero-posterior forces may lead to open book injuries (such as motor vehicle accidents). The pelvic floor generally remains intact while lateral forces (side impacts) lead to injuries of the posterior ligaments. Vertical forces (such as falls from heights) may lead to damage to the ligaments and pelvic floor that lead to significant instability in the posterior pelvis.

Patients should also be questioned for bladder tenderness, last urination and defecation time, last oral intake time, medical history, drugs and allergies, menstruation time and pregnancy status of females.

Rotation of the iliac wings indicates a severe pelvic fracture on inspection. Differences in limb length may be associated with hip injury or unstable or displaced hemipelvis. Careful inspection of the skin and skin folds is important for the detection of open fractures. Perineal ecchymosis or hematoma, Cullen’s sign, and Grey Turner sign are late findings and may be visible due to retroperitoneal hemorrhage and intraabdominal hemorrhage on the periumbilical or flank section. (Image 8 and 9)

In conscious patients without distracting injury, tenderness on palpation between the symphysis pubis, sacrum and the sacroiliac joint may be a symptom of pelvic injury. Manipulation of the pelvis should be kept minimum because of the increased risk of hemorrhage due to the break down of clots that formed around the pelvic fracture. Hence, in an unstable pelvic fracture, the recurrent physical examination is contraindicated.
Presence of blood in the penile meatus should be noted. A digital rectal examination should be made to reveal the anal sphincter tone, prostate position and integrity, presence of mucosal disruption and bleeding caused by bone ends. Also, a digital vaginal examination should be done to detect open fractures in females.

Pulse and motor and sensory examination of the lower extremities should be evaluated.

Emergency Diagnostic Tests and Interpretation

Plain Radiography

ATLS guidelines recommend plain pelvic radiography for patients who have signs of pelvic injury on physical examination, severe trauma mechanism, suppressed awareness or distracting injury.

The method for evaluation of plain pelvic radiography is described in here.

Sacral fractures and sacroiliac joint injuries may not be seen on AP view. Inlet and outlet x-ray views increase sensitivity and specificity for the diagnosis of pelvic fractures in patients who have posterior pelvic tenderness but normal findings in anterior evaluation. (see image 10 a,b and 11 a,b)

Image 10 a. Inlet view

Image 10 b. Inlet view

Image 11 a. Outlet view

Image 11 b. Outlet view

Avulsion fractures of the L5 transverse process, avulsion fractures of adhesion places of sacrospinous and sacrotuberous ligaments, avulsion of lower lateral lip of the sacrum and vertical sacral fractures that extend to medial part of sacral foraminae may show an unstable pelvic fracture exclusively.

Computed Tomography

• CT is the gold standard for evaluation of pelvic injuries.
• CT should be used when the clinical suspicion is high, but the plain pelvic radiograph is negative.
• CT identifies secondary injuries in patients with pelvic fractures on x-ray.
• It is preferred in suspected acetabular fractures.
• Contrast-enhanced CT gives useful data for evaluation of soft tissue injuries, vascular injuries, and pelvic hematoma.
• The presence of arterial bleeding is 80-90% recognizable with CT.

Emergency Treatment Options

There is no standardized protocol for the treatment of pelvic injuries. Treatment options should be based on the hemodynamic status, the severity of trauma, the mechanism of injury, the type of fracture, and concomitant injuries.

Resuscitation

• All critically ill patients should be given oxygen and intravenous fluids.
• Lower extremity veins should not be preferred as an intravenous line in patients with severe pelvic fracture because of the risk of leak into the retroperitoneal space.
• Opioids may be given for pain control.
• Antibiotics should be given for patients with bowel rupture, urogenital injury, and an open fracture.
• Tetanus prophylaxis is applied to appropriate patients.
• Crystalloid fluids and blood products may be required in patients with a pelvic injury.
• Open book injuries, fractures that cause separation of more than 0.5 cm in the pelvic ring, and fracture findings that include displacement at symphysis pubis or obturator ring may need the blood transfusion.
• Hemodynamically unstable patients, due to hemorrhagic shock caused by trauma, should be treated considering the ATLS guidelines.

Control of Hemorrhage

Treatment choice should be selected according to the capacity of the health center with an emergency physician, an orthopedic surgeon and an interventional radiologist to take control of pelvic hemorrhage.

 

Mechanical stabilization

• The bed linen is wrapped tightly around the pelvis as a simple non-invasive technique. Please see below videos.

 

• Sheets must be wrapped to pass through the center of the trochanters instead of iliac crests.
• Open book injuries get the most benefit from bed linen wrapping method.
• This maneuver may aggravate the degree of the displacement in lateral compression injuries because of the internal rotational strain.
• External fixation and extraperitoneal packing may be preferred by the orthopedic surgeon as invasive treatment options.

Angiographic Embolisation

Posterior pelvic ring injuries are associated with the most severe hemorrhages. The majority of pelvic bleeding has the venous origin. Arterial hemorrhages account for 10-15%.

Shock and death are associated more with arterial bleeding.

Angiography is indicated in patients with a major pelvic fracture who have resistant hypovolemia, although other resources for bleeding are under control .

Angiographic embolization is reported to be effective at controlling arterial bleeding, while external fixation is reported to be effective at controlling venous hemorrhage. However, it is difficult to determine the origin of the hemorrhage whether venous or arterial until angiography is applied.

Complications

Timely intervention is crucial for prevention of complications.
Life-threatening hemorrhage, deformity, neurological and genitourinary injuries are complications that should be diagnosed and treated in pelvic traumas.

Early Complications

• Hemorrhagic shock
• Urethral injury
• Bladder injury
• Vaginal laceration
• Rectal injury
• Perineal injury
• Limbo-Sacral nerve root injury

Late complications

• Chronic pain
• Sexual dysfunction
• Shortening of extremity
• Malunion or nonunion

Pediatric, Geriatric, Pregnant Patients and Other Considerations

The risk of hemorrhage is higher in pediatric patients. Child abuse should be considered. There is an increased risk of uterine rupture in pregnant patients. Consider deep vein thrombosis prophylaxis in non-ambulatory geriatric patients with stable pelvic fractures.

Disposition Decisions

Admission criteria

• Tile type B or C pelvic fractures
• Acetabular fractures
• Pelvic fractures with other system injuries

Discharge Criteria

Hemodynamically stable Type A pelvic fractures with no evidence of other system injuries.

References and Further Reading

• Pelvic Fracture in Emergency Medicine. Author: C Crawford Mechem, Md, Ms, Facep  Chief Editor: Trevor John Mills, Md, Mph.Http://Emedicine.Medscape.Com/.
• Complications Associated With Fractures Of The Pelvis. Lf, Peltier.1965, J Bone Joint Surg, S. 47:1060.PMID:14318624
• Pelvic Fractures: Epidemiology And Predictors Of Associated Abdominal İnjuries And Outcomes.Demetriades D, Karaiskakis M, Toutouzas K, Alo K, Velmahos G, Chan L. J Am Coll Surg. 2002 Jul;195(1):1-10. PMID:12113532
• Moreno C, Moore Ee, Rosenberger A, Et Ak Hemorrhage Associaled With Major Pelvic Fracture: A Multispecialty Challenge. J Trauma 26:987- 994,1986. PMID:3783790
• Emergency Department Evaluatıon And Treatment Of Pelvıc Fractures Paolo T. Coppola, Md, And Marco Coppola, Do, Facep Emergency Medıcıne Clınıcs Of North Amerıca Volume 18 Number 1 February 2000. 
• Rosen’s Emergency Medicine: Concepts And Clinical Practice, 7th Edition, Chapter 52. 
• Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 7th Edition Chapter 269. 
• https://Www.Youtube.Com/Watch?V=Jpscugjra8g.
• https://Www.Youtube.Com/Watch?V=D4_R7y-C7lu.
• https://Www.Youtube.Com/Watch?V=81csco3qy3s.
• Young Wjr, Burgess Ar. Radiologic Management Of Pelvic Ring Fractures: Systemic Radiographic Diagnosis. Baltimore: Urban And Schwarzenberg; 1987. 
• Tile M. Fractures Of The Pelvisand Acetabulum.3rd Ed. Baltimore: Williams&Wilkins;1995. 
• Templeman D, Tornetta P. Pelvic And Acetabular Fractures.In: Jeffrey S, Fischgrund, Editors. Orthopaedic Knowledge Update 9. Rosemont, Il: Amer Academy Of Orthopaedic2008. P. 389-98. 
• Kellam Jf, Mcmurtry Ry, Paley D, Tile M.The Unstable Pelvic Fracture. Operative Treatment.Orthop Clin North Am. 1987 Jan;18(1):25-41.PMID: 3796960. 
• Emerg Med Clin North Am. 2010 Nov;28(4):841-59. Doi: 10.1016/J.Emc.2010.07.002. 
• J Trauma Acute Care Surg. 2013 May;74(5):1363-6. Doi: 10.1097/Ta.0b013e31828b82f5. PMID:23609291
• https://Www.Youtube.Com/Watch?V=-X_Al_Ibnxe.
• https://Www.Youtube.Com/Watch?V=Omg79ced6s0.
• Management And Treatment Of Pelvic And Hip İnjuries.Williams-Johnson J, Williams E, Watson H. Emerg Med Clin North Am. 2010 Nov;28(4):841-59. Doi: 10.1016/J.Emc.2010.07.002. PMID:20971394
• Rosen And Barkin’s 5-Minute Emergency Medicine Consult 5th Editionauthor(S):Jeffrey J. Schaider, Md And Roger M. Barkin, Md, Mph, Et Al. Publisher: Wolters Kluwer Health | Lippincott Williams & Wilkins.