Pelvic Ring Injuries

Due to the high energy nature of pelvic ring injuries, associated morbidities require thorough assessment. Incidence of associated trauma includes:

• Chest trauma 63%
• Long bone fractures 50%
• Head injuries 40%
• Visceral organ damage 40%
• Spinal fractures 25%
• Intestinal injuries 14%
• Genitourinary injuries 6 to 15%
• Open fractures 5%
  • Mortality of open pelvis fractures is around 50%; urgent antibiotic administration is necessary
  • Perform a rectal and vaginal exam and look for breaks in the skin around the perineum

A pelvic ring injury can be a life-threatening injury or may be associated with a life-threatening injury, and a thorough exam is necessary.

• Advanced trauma life support (ATLS)
• Motor and sensory exam
• Physical exam of the pelvis including push/pull test and lateral compression test
• Look for leg length inequality not explained by a limb fracture.
• A high riding prostate or blood at the urethral meatus may indicate a genitourinary injury.
• Rectal and/or vaginal exam
• Perineum exam may reveal swollen and/or mobile genitalia.

Destot Sign – Palpable hematoma in the perineum above the inguinal ligament or proximal thigh may represent pelvic fracture with active bleeding.

Grey Turner Sign – Flank bruising indicative of retroperitoneal bleeding.

Morel-Lavallee Lesion – Internal degloving injury from skin shear at time of injury, may require intervention and may affect surgical planning, look for significant soft tissue abrasions, ecchymosis, or subdermal hematoma. May also be identified on CT scan with the assessment of soft tissues.[1][2]

Imaging                       

• Xrays – CXR, AP pelvis
  • Inlet view – allows evaluation of anterior or posterior translation.
  • Outlet view – allows evaluation of coronal plane deformity.
  • Flamingo views – for assessment of chronic pelvic ring instability
• CT scan – should be obtained for all pelvic ring injuries.
  • Helps to assess the extent of the sacral injury
• MRI – rarely indicated in acute pelvic ring trauma

Classification

Tile Classification[1]

Type A – Stable

• A1 – Fractures not involving the pelvic ring
• A2 – Stable minimally displaced fractures of the pelvic ring

Type B – Rotationally unstable, vertically stable

• B1 – Open book
• B2 – Lateral compression ipsilateral
• B3 – Lateral compression contralateral

Type C – Rotationally and vertically unstable

• C1 – Unilateral
• C2 – Bilateral
• C3 – Associated with an acetabular fracture

Young and Burgess Classification[7]

• Lateral Compression (LC)
  • LC1 – Anterior sacral compression fracture +/- pubic rami fractures (often a stable pattern)
  • LC2 – Crescent fracture +/- pubic rami fracture (unstable)
  • LC3 - LC 1 or 2 with a contralateral APC injury
• Anterior-Posterior Compression (APC)
  • APC1 – Minor symphysis widening or distracted ramus fracture
  • APC 2 – Opening of symphysis greater than 2.5 cm, disruption of sacrospinous and anterior SI ligaments, assumes posterior SI ligaments remain intact
  • APC3 – Complete disruption of symphysis and SI joint
• Vertical Shear (VS)
  • VS – Vertical displacement of hemipelvis represents complete instability.
• Combined Mechanism (CM)
  • CM – Any combination

Denis Classification of Sacral Fractures[2]

• Zone 1 – Lateral to the sacral foramen
• Zone 2 – Entering sacral foramen
• Zone 3 – Medial to sacral foramen – Highest incidence of neurologic injury including nerve root or cauda equina

Lumbopelvic Dissociation[8]

• Fracture pattern which renders the base of the spine discontinuous with the pelvis requiring fixation
• Beyond the scope of this activity
• Bilateral sacral fractures have a high incidence of lumbopelvic dissociation, and CT scan should be reviewed carefully for coronal plane sacral disruptions

Recognize that a pelvic ring injury may represent a life-threatening emergency and work as a team to resuscitate critically injured patients rapidly

• ATLS first
  • If a patient has a pelvic ring injury, do not assume they do not have another source of hemorrhage.
  • A pelvic ring injury should remind all practitioners of high energy trauma and perform a thorough assessment of all body systems.
  • Exclude thoracic and abdominal bleeding before assuming a patient's hemorrhage is from a pelvic ring injury.

Hemorrhage Associated with High Energy Trauma and Pelvic Ring Disruption[7]

Pelvic ring injuries can have significant blood loss from sources, including:

• Pelvic venous plexus (a common source of hemorrhage in 80% of cases): can lead to a retroperitoneal hematoma, which can hold up to 4 Liters of blood.
• Osseous blood supply, including nutrient arteries and bleeding cancellous bone.
• Arterial injury (uncommon source of hemorrhage in 10-20% of cases), the following arteries can be involved; superior gluteal artery most common in  APC injuries, internal pudendal and obturator arteries in LC injuries.

Initial Management and Resuscitation

Resuscitation

Ideally, a transfusion of PRBC:FFP: Platelets at a ratio 1:1:1 has been reported to improve mortality in cases where massive transfusion is necessary.

Pelvic Binder/Circumferential Sheet Placement[9]

• Temporary intervention to partially reduce the displacement of a pelvic ring injury and should be placed at the level of the greater trochanters. Adding stability will help with clot formation within the pelvis and limit hemorrhage. It is controversial whether this actually changes the pelvic volume.
  • Indications
    • Hemodynamically unstable pelvic ring injuries including APC and VS injuries
    • LC injuries treated with binder may be over-compressed and may cause harm to other structures in the pelvis.            
  • Contraindications
    • Acetabular fractures
• May mask an injury from being identified.
  • If the patient is hemodynamically stable on arrival without radiographic evidence of a pelvic ring injury, remove the binder and obtain repeat imaging.[10]

 Angiography/Embolization[11]

• Pelvic ring injuries that remain hemodynamically unstable despite transfusion and binder placement should undergo further intervention. At most centers, the next step is angiography and embolization. External fixation and open pelvic packing are the next steps at some centers; however, this is controversial.
• CT angiography confirms the presence or absence of ongoing arterial hemorrhage with 98 to 100% negative predictive value.
• Ongoing bleeding after selective embolization indicates bilateral temporary internal iliac embolization, which can be effective. But, on the other side can be complicated by gluteal necrosis and impotence.

 External Fixation[12]

• Pelvic clamp or traditional frames.
• Indicated as a temporary or definitive fixation for unstable injuries with hemodynamic instability, injuries with external rotation component, and symphyseal widening with fecal or urinary contamination.
• It allows nursing in an upright position with the advantage of improving ventilation, especially in patients with chest trauma.
• Pin positions for frames: Gluteal pillar, Anterosuperior (into the iliac crest), or anteroinferior ( supraacetabular). Supraacetabular pin placement, under fluoroscopic guidance, has the advantage of a significant increase in the stability of the sacroiliac joint [13]. On the other side, the risk of injury to the lateral femoral cutaneous nerve is higher with supraacetabular pin placement.[14]
• Contraindicated in the ilium and acetabular fractures.

Anterior Subcutaneous Pelvic Fixator (INFIX)[15]

• New technique to avoid complications associated with pelvic external fixation including pin site infection   

Diverting Colostomy

• It may be necessary for open pelvic ring injury with perineal trauma.

Definitive Management

Non-operative: indicated for stable fractures such as type I APC and LC injuries. Pubic rami fractures are managed conservatively as surgical dissection necessary for fixation outweigh the benefits.[16]

Operative: indicated in unstable fractures such as APC and LC types II and III and VS Injuries. Operative intervention is relatively indicated in type I APC and LC injuries if there is significant displacement as indicated by lower limb rotational deformity resulting in complete loss of rotation or leg length discrepancy of 1.5 cm or more. Other relative indications include associated trauma necessitating laparotomy, tilt fracture protruding into the perineum, and refractory pain.[17]

Open Reduction Internal Fixation[18]

• ORIF results in improved quality of reduction and better biomechanical stability when compared to external fixation.
• Plates and screws across the symphysis can support the anterior ring.
• Parasymphyseal pubic ramus fracture is treatable with open plating or percutaneous screw fixation.
• SI dislocation or sacral fracture can be treated with sacroiliac, transiliac transacral, or transiliac screws percutaneously. A thorough understanding of pelvic ring osseous fixation pathways is necessary to perform these techniques safely. Sacral dysmorphism is common and can complicate safe percutaneous fixation of the posterior pelvic ring.[19]
• Open plating of SI joints or sacral fractures may be necessary if a closed reduction is unobtainable or the fracture pattern is not amenable to percutaneous fixation.
• Approaches: Pfannenstiel, Stoppa, or ilioinguinal approaches can be used to gain access to anterior structures. Posterior approaches are indicated in cases of inadequate reduction of the sacroiliac joint or associated sacral fractures.

Percutaneous Fixation

• Iliosacral screw fixation for instability of the posterior ring is a popular technique. especially with traumatized posterior skin that would breakdown with ORIF.[20]
• The most common complications are nerve root injury, errantly placed screws, and loss of reduction.[21]

 Triangular Osteosynthesis[8]

• Lumbosacral pedicle screw fixation combined with a sacroiliac fixation for management of lumbopelvic discontinuity.
• Absolute indications are still unclear.

The timing for definitive fixation is controversial. Early definitive fixation is advantageous for pain relief, easier nursing care, better reduction quality, bleeding control, and early mobility. but that at the expense of increased bleeding risk and possible second hit in trauma patients who are not fully resuscitated.[22][23][20]

Differential Diagnosis:

• The pelvic ring should never be unstable without an injury
• The only exception is in pregnant women who may have pelvic ring instability or widening temporarily around the time of parturition

Sagi et al 2011 JOT[24][25]:

• Dr. Sagi and colleagues evaluated pelvic ring injuries under dynamic fluoroscopy in the operating room and found a subset of pelvic ring injuries to be more unstable than predicted by fracture pattern alone. 
• Which patients require examination under anesthesia (EUA) still requires clarification.
• Can use EUA during fixation of pelvic ring injuries to determine how much fixation is required.

The sequence of Events for Treating a Pelvic Ring Injury

On arrival:

• ATLS
  • Two large-bore IVs
  • Foley catheter
    • Contraindicated if blood at the urethral meatus
    • Indications for a retrograde cystourethrogram
      • Male patients with symphysis disruptions, hematuria, blood at meatus, inability to void, ecchymosis or hematoma of the perineum, high-riding or boggy prostate
  • Rectal and vaginal exam
  • Hemodynamic instability treated with fluids vs. immediate blood products.
• CXR
  • High energy trauma may also have widened mediastinum or pneumothorax.
• AP Pelvis
  • Try to decipher between APC and LC/VS/CM injury patterns.
    • If the symphysis has significantly widened its likely an APC pattern
      • If the symphysis is wide and the patient is hemodynamically unstable, apply a pelvic binder or circumferential sheet.
    • If the pelvis is broken/disrupted, but it is not clearly an APC pattern, consider other interventions before a pelvic binder.
      • Traction for a VS injury 
• CT head, neck, chest, abdomen, and pelvis
  • Fine cuts (2 mm) of the pelvis
  • Look for other injuries, including head/neck/chest/abdominal/pelvic hemorrhage.

• If the patient remains hemodynamically unstable
  • Identifiable source of bleeding outside of pelvis:
    • Control by other means per general surgery recommendations
  • No other source of bleeding identified other than pelvic ring injury: 
    • Interventional radiology embolization
      • Best next step in most centers
    • Emergent pelvic external fixation and pelvic packing
      • Controversial

• Once the patient is hemodynamically stable
  • Inlet and outlet X-rays of the pelvis
    • For surgical planning
  • If the patient has polytrauma, it indicates a reason for the delay of definitive surgical intervention.
    • Temporary external fixation per damage control orthopedic principles
  • If the patient is stable (lactate corrected)
    • Definitive fixation

Young-Burgess Classification Predicts Mortality[26]

• Combine the classification into stable (LC1, APC1) vs. unstable (LC2,3 APC 2,3)
  • Stable – mortality of 7.9%
  • Unstable – mortality 11.5%

Reduction of the posterior ring within 1 cm improves long term outcomes.

Return to work rate is highly variable, with most patients reporting some form of persistent impairment.[27]

• 24% lose a job
• 34% returned to work but changed duties
• 46% unable to perform pre-injury duties

Male gender and older age have higher mortality.

Females with symphysis fixation can still have safe vaginal deliveries.[28][29]

• As long as the front and back of the pelvis are not both restrained by fixation

Malunion[30]

• Controversial how to define or measure displacement and malunion
• Patient with anatomic reductions have better outcomes, but displacement less than 1 cm are often tolerable
• Sometimes difficult to discern stable patterns from unstable patterns
• May consider manipulation under anesthesia to determine stability in select cases or to guide treatment during surgery
• Complete sacral fractures with ipsilateral rami fractures treated nonoperatively will displace over time 39% of the time
• Complete sacral fractures with bilateral rami fractures treated nonoperatively will displace over time 68% of the time

Hardware Failure[31]

• Micromotion is present even in a well-aligned and healed pelvic ring. Therefore, there is a high rate of hardware failure over time. If the pelvic ring has healed, there should be no displacement if and when the hardware fails; this is not an indication for hardware removal
• Plating across the symphysis has a hardware failure rate of 43% at one year
• 97% of hardware failures were asymptomatic

 Neurologic Dysfunction

• Denis 3 fractures of the sacrum have approximately a 50% rate of neurologic dysfunction of lumbosacral nerve roots.

 Sexual Dysfunction[32][33]

• Erectile dysfunction occurs in 46% of males after pelvic ring injury
• Dyspareunia occurs in 56% of females after pelvic ring injury, 91% with APC injuries, and 79% of patients treated with symphysial plating

 Chronic Pain and Disability

• See prognosis section

Infection[34]

• As high as 16% with a posterior approach to the sacrum
• Obesity increases the risk of complications and reoperation

DVT/PE[35]

• Pelvic ring injury may require IVC filter

Depending on the specific injury and treatment method, the patient may require a period of weight-bearing restrictions to one or both extremities. Nursing and therapy will be necessary to assist with a patient's return to function. DVT prophylaxis postoperatively is paramount. 

Clinicians need to address patient expectations early. Discussing reasonable outcomes and understanding some degree of chronic discomfort may be unavoidable. Also, discussing some intimate issues like erectile dysfunction or dyspareunia is important to patient well-being and making necessary referrals to OB-GYN or urology as necessary. 

Patients with pelvic ring injuries are typically very sick and will require the assistance of multiple providers. Each provider must discuss their role with other providers and the patient. There may be multiple teams working on a single patient in complex scenarios, and interprofessional communication is essential. Because of the complexity of these injuries, the number of organs injured, and the high morbidity and mortality, it is imperative that an interprofessional team be involved in patient care. The brief roles of the interprofessional team are as follows:

The urologist may be required if there is a urethral injury; since these patients require suprapubic catheterization. Further, it is imperative that the catheter not be placed in the way of a diverting ileostomy for the general surgeon or a pelvic incision for the orthopedic surgeon. Diverting ileostomy/colostomy or suprapubic catheters should be placed as cephalad as possible to avoid interfering with the surgical incisions needed to operate on the pelvis.

A general surgeon may be required to divert the fecal flow by creating a diverting ileostomy or colostomy.

The radiologist is essential for localizing the injuries and their extent. Also, an interventional radiologist may be necessary for arterial embolization in cases of uncontrolled hemorrhage.

These patients are often managed in the trauma or surgery ICU and need close monitoring by the nurses. These patients also need DVT and pressure sore prophylaxis. Since most patients cannot eat an oral diet for a few days or weeks, a dietary consult for TPN may be required. If the patient has a stoma, a stoma nurse needs to educate the patient and the family about stoma care, the necessary changes in diet, maintaining hygiene around the appliance, and reporting back to the physicians of any issues encountered.

Pain control and antimicrobial therapy may be necessary, and the pharmacist should oversee medication reconciliation and dosing and let the team know of any potential interactions or dosing issues.

Because these patients are often bedridden for prolonged periods, physical and occupational therapy must be involved to exercise the muscles and maintain function. They can inform the team about the progress or lack thereof as the patient moves through the stages of rehabilitation.

A mental health nurse should see the patient before discharge as depression and anxiety are common after pelvic trauma. The road to recovery is long and unpredictable, causing extreme stress in many patients. These findings should go to the managing physician(s) as well as the nursing team.

Most patients require extensive rehabilitation after discharge and may need to follow up with many specialists, including the nurse practitioner.

In summary, as can be seen above, pelvic ring injuries/fractures require an interprofessional team approach, including physicians, specialists, specialty-trained nurses, and pharmacists, all collaborating across disciplines to achieve optimal patient results. [Level V]

Outcomes

Pelvic trauma is a significant event, and despite optimal care, it correlates with very high morbidity. Many patients remain disabled after the injury and are not able to return to work. Most have difficulty performing daily living activities and often require assistance with ambulation. The long term prognosis for most of these patients is guarded.