Chapter 35: Pelvis

Pelvic injuries (PI) are frequent, particularly after blunt trauma (9% of all blunt trauma patients), and range from clinically insignificant minor pelvic fractures to life-threatening injuries that produce exsanguination (0.5% of all blunt trauma patients). The overall mortality rate of patients with pelvic ring fractures is approximately 6%. Uncontrolled pelvic hemorrhage accounts for 39% of related deaths, whereas associated head injury is responsible for 31% of the deaths. AP compression and vertical shear injuries are associated with a higher incidence of pelvic vascular injury and hemorrhage. There is little agreement about the preferred methods of management and, therefore, guidelines are vague or not followed. However, the recent evolution of rapid pelvic stabilization by external fixation or pelvic binding and of bleeding control by angiographic embolization or preperitoneal pelvic packing has significantly decreased the mortality rates of devastating PI. A multidisciplinary approach is crucial, as no single specialty has all the skills or controls all the resources that can be used to produce ultimately outcomes. Emergency medicine physicians, trauma and critical care surgeons, orthopedic surgeons, and interventional radiologists should play protagonist roles in a well-orchestrated trauma team that manages these complex patients.

The pelvic ring comprises the sacrum and the two innominate bones, all attached with strong ligaments. The innominate bones join the sacrum at the sacroiliac joints and each other anteriorly at the pubic symphysis. The anterior and posterior sacroiliac ligaments include shorter and longer elements that extend over the sacrum and to the iliac crests, and provide vertical stability across the sacroiliac joints. The pelvic floor is bridged by the sacrospinous and sacrotuberous ligaments that connect the sacrum to the ischial spine and the ischial tuberosity, respectively. The anterior elements, including the pubic rami and pubic symphysis, contribute to approximately 40% of the pelvic stability, but the posterior elements are more important, as shown by biomechanical studies.

The internal iliac (hypogastric) arteries provide blood supply to the organs, bones, and soft tissues of the pelvis. The anterior division includes the inferior gluteal, obturator, inferior vesicular, middle rectal, and internal pudendal artery. The posterior division includes the iliolumbar, lateral sacral, and superior gluteal artery. The largest branch is the superior gluteal artery, which is the most commonly injured major arterial branch after pelvic fractures. Pelvic veins run parallel to the arteries and form an extensive plexus that drains into the internal iliac veins. The sacral venous plexus is adhered to the anterior surface of the sacrum and shredded after major pelvic fractures. Venous bleeding is more frequent than arterial bleeding after PI.

The sciatic nerve is formed by the nerve roots of L4 to S3 and exits the pelvis under the piriformis muscle. The anterior roots of L4 and L5 cross the sacroiliac joints and can be injured in sacral ala fractures or sacroiliac joint dislocations.

All pelvic organs are at risk of injury following severe PI with the bladder and urethra being the most frequently injured. The extraperitoneal rectum is also at risk in open pelvic fractures.

Despite multiple classification systems described, the two most commonly used are those described by Tile^1,2 and Young–Burgess.^3,4

The tile classification categorizes pelvic fractures in three groups based on stability, as evaluated primarily by clinical examination and plain radiographs (Table 35-1):

• Type A fractures are stable, as the posterior ligaments are intact. These fractures include transverse sacral, iliac wing, pubic rami, pure acetabular, and chip and avulsion fractures.

• Type B fractures are caused by internal and external rotational forces and are “partially” stable (vertically stable but rotationally unstable). They include open-book and bucket-handle fractures (Figs. 35-1, 35-2, 35-3).

• Type C fractures are vertically and rotationally unstable, as they involve a complete disruption of the sacroiliac complex (Fig. 35-4).

The Young–Burgess classification divides pelvic fractures according to the vector of the force applied into anteroposterior compression (APC), lateral compression (LC), and vertical shear fractures (Table 35-2):

• APC injuries are produced by forces applied in the sagittal plane, as is usually the case with motor vehicle crashes. APC-I injuries may result in a small widening of the pubic symphysis (<2.5 cm) but the posterior ligaments are intact. APC-II injuries include tearing of the anterior sacroiliac ligaments, as well as the sacrospinous and sacrotuberous ligaments, but the posterior sacroiliac ligaments are intact. The pubic symphysis diastasis may be more than 2.5 cm. Rotational instability is usually present and hemorrhage more likely. APC-III injuries are caused by high-energy transfer and the posterior sacroiliac ligaments are disrupted, causing full instability of the hemipelvis with a high likelihood of bleeding, nerve damage, and organ injuries.

• LC injuries are produced from lateral impacts across the horizontal plane, also common with motor vehicle crashes. LC-I injuries include transverse fractures of the anterior ring or impacted sacral fractures and are typically stable. LC-II injuries are caused by higher-energy forces that produce tearing of the posterior sacroiliac ligament and displacement of the sacroiliac joint or an oblique fracture of the ilium, the superior part of which remains attached to the sacrum, while the inferior is mobile (crescent fracture). Depending on the force applied, this fracture can be stable or unstable. LC-III injuries are severely unstable fractures, as the lateral force continues to compress and rotate the hemipelvis to the point of complete destruction of the sacroiliac joints, as well as the sacrospinous and sacrotuberous ligaments. Neurovascular and organ injuries are common.

• Vertical shear injuries are typically produced by a fall from a height and involve anterior (pubic rami, pubic symphysis) and posterior (sacroiliac complex) fractures. Typically, they are unstable.

• Combinations of the above types produce a variety of fracture patterns, most commonly involving LC and vertical shear injuries. Nearly one-third of PI patients have combination injuries.

Physical examination will establish the suspicion for a PI and assess for pelvic instability. With the examiner’s hands on the anterior iliac spines of the patient, a gentle compression toward the midline, as well as a mild anteroposterior movement of the hands, will provide evidence of pelvic instability. This must be done by an experienced physician who will interrupt the motion immediately if instability is produced. Aggressive handling of the pelvis, such as “rocking,” is discouraged because it produces pain, bleeding, and aggravation of the injury. Inspection of the perineum is critical to diagnose lacerations or hematomas, which are further indications of significant PI. In a study of 66 patients with Glasgow Coma Score over 12, a focused physical examination protocol, including posterior palpation of the sacrum and sacroiliac joint, anteroposterior and lateral iliac wing compression, active hip range of motion, and a digital rectal examination, resulted in 98% sensitivity and 94% specificity for the detection of posterior pelvic fractures.⁵

The plain anteroposterior pelvic film is part of the radiographic routine for blunt trauma. However, many studies indicate that in patients with a negative clinical exam for PI, the pelvic film is unnecessary. In a review of 743 blunt trauma patients with no pain or other clinical findings of PI, only 3 patients (0.4%) had a pelvic fracture.⁶ In all cases it was a single, nondisplaced pubic ramus fracture that required no treatment. In another study of 686 blunt trauma patients, 311 received a pelvic film, which carried a false-negative rate of 32%.⁷ Of the 375 patients who did not receive a pelvic film, 3% of the patients (13) were found to have small pelvic fractures, none of which required treatment. So, it seems that a routine pelvic film in asymptomatic patients is not useful. Similarly, a pelvic film in patients who have symptoms may be inadequately sensitive and, therefore, might be omitted in favor of a CT scan. In a study of 397 multiple injured patients who had a pelvic film and a CT scan, 43 patients had 109 pelvic fractures.⁸ The plain film did not diagnose 51 (47%) of the fractures in 9 (21%) patients. Iliac and sacral fractures were most frequently missed. The authors concluded that a screening pelvic film is unnecessary after blunt multitrauma.

Pelvic inlet and outlet films provide information about the anteroposterior displacement of the injury (inlet films) and vertical displacement (outlet films). CT scan with reconstructions (and recently three-dimensional reconstructions) has essentially replaced all other diagnostic modalities and is routinely performed to accurately characterize pelvic fractures, as well as identify associated pelvic organ injuries and hematomas (Fig. 35-5). Intravenous contrast is routinely administered, unless there is a contraindication. Oral and rectal contrast is not necessary for blunt trauma. Magnetic resonance imaging does not offer a distinct advantage over CT scan and is only considered if radiation exposure becomes an issue, as it is with pediatric patients, pregnant patients, or repeat imaging. On occasions, the ligaments need to be evaluated in more detail and this can be done with higher accuracy by magnetic resonance.

The diagnostic peritoneal lavage has nearly completely disappeared from the algorithms of diagnosis of abdominal bleeding in modern trauma centers. On occasions, we use the aspiration portion of it only (diagnostic peritoneal aspiration) to detect any large volume of intraperitoneal bleeding.⁹ We perform it percutaneously and, when a PI is suspected, supraumbilically. The Focused Abdominal Sonography for Trauma (FAST) exam has become a routine part of the initial evaluation and screening for intra-abdominal fluid. In PI a number of findings can be useful: (1) the absence of intraperitoneal fluid in a hemodynamically unstable patient indicates the presence of a major retroperitoneal hemorrhage from PI; (2) a distorted bladder contour indicates the presence of a compressing pelvic hematoma; (3) the presence of intraperitoneal fluid indicates that intraperitoneal organ injury must be excluded by additional diagnostic methods or laparotomy.

As soon as significant pelvic bleeding is suspected, the patient should be resuscitated per routine and a decision should be made for additional diagnostic tests or immediate intervention. The concept of hypotensive resuscitation (ie, allowing a lower than normal blood pressure during the early phases of resuscitation in order to prevent ongoing hemodilution and bleeding) has been adequately established for penetrating trauma.¹⁰ However, it is not universally accepted for blunt trauma despite the encouraging reports.¹¹ The coexistence of neurologic injuries, which have been shown to produce worse outcomes in the presence of hypotension, is the main deterrent to allow a low blood pressure in a hemodynamically unstable blunt trauma patient. In a recent prospective randomized study from 19 emergency medical services of the Research Outcomes Consortium, 192 hypotensive trauma patients were assigned in the prehospital setting to receive crystalloid resuscitation in order to maintain a blood pressure above 70 mm Hg (controlled resuscitation group) or above 110 mm Hg (standard resuscitation group). There was no difference in most outcomes but patients with blunt trauma in the controlled resuscitation group had a lower 24-hour mortality (3%) compared to the standard resuscitation group patients (18%). Although we still need phase III studies to evaluate the different resuscitation regimens, this study offers further proof that limiting the initially crystalloid resuscitation does not harm and may benefit hypotensive trauma patients of any type of injury.¹² We espouse the principles of hypotensive resuscitation even in blunt trauma and are very cautious with our early resuscitation efforts, rarely using massive crystalloid infusions. If we suspect correctable bleeding sites, we strive to control bleeding as early as possible and then assume full resuscitation. We pay particular attention to substitute lost blood with blood and blood product transfusion rather than acellular fluids, and we decrease the ratio of packed red blood cells to fresh frozen plasma to as close to 1:1 as possible.¹³ However, it must be noted that after a number of retrospective and prospective uncontrolled studies trumpeted the value of the 1:1 ratio, the only randomized study on this issue failed to show any difference in outcomes. The large, multicenter, National Instituted of Health supported, PROPPR trial randomized 680 severely injured patients to receive a ration of plasma to platelets to red blood cells of 1:1:1 or 1:1:2.¹⁴ There was no difference in 24 hours or 30 days mortality between the two groups, nor in the rate of complications. Therefore, one could conclude that it is not the exact 1:1:1 ratio that improves outcomes but the attention to hemostatic resuscitation and the need to enhance coagulation by appropriate infusion of plasma and platelets when major blood loss is predicted. We are not convinced about the effectiveness of recombinant factor VIIa, given that there is no level 1 evidence, supporting the use of this very expensive medication.¹⁵ The only prospective randomized study was flawed by excluding early deaths.¹⁶ The benefit of patients who received recombinant factor VIIa compared with placebo was modest at best, a reduction of blood transfusions by 2.6 U among blunt trauma patients. There was no benefit among penetrating trauma patients. Therefore, we use recombinant factor VIIa only as rescue therapy in very selected cases, if at all. Tranexamic acid is an antifibrinolytic agent that was shown to prevent all-cause mortality and death from bleeding in a prospective randomized trial of 20,211 trauma patients recruited in 274 hospitals from 40 countries.¹⁷ The study has been subjected to criticism, given the relatively small absolute difference of death from bleeding between the tranexamic acid and control groups (4.9% vs 5.7%), which achieved a strong statistical significance (p = 0.0077) due to the very large sample size. In addition, the reverse effect (increase in mortality) was observed when tranexamic acid was given after 3 hours from injury. No US hospital participated in this study.

Pelvic Binders

Unstable pelvic fractures produce bleeding because of ongoing injury to small vessels, as the fractured elements continue to move, and because of the increased volume of the pelvis, as it happens in open-book fractures. Significant bleeding continues unchecked prehospitally and in the emergency department, as the therapeutic choices to counteract these two mechanisms are limited. Pelvic binders address temporarily these two issues by stabilizing the pelvis to stop the movement of the fractured elements and by decreasing the retroperitoneal volume (Fig. 35-6). The former effect can be produced by simply applying a binder with mild to moderate LC of the pelvis. The latter effect is possible only if the device applies significant compression in order to reduce an open pelvis and decrease the volume available for blood to spill. However, significant LC can create the opposite effect, if applied on the wrong type of fracture. For example, a moderately displaced LC fracture can become worse, if excessive compression is applied by a pelvic binder (Fig. 35-7). Under these principles, simple stabilization by a pelvic device is desirable in all unstable fractures but significant compression should only be used in certain fractures, most commonly those of the open-book variety.

The military antishock trousers (MAST) garment became popular in the 1980s after initial reports of improved survival in patients with multiple injuries. However, in 1989 a definitive prospective randomized study found it to be associated with increased mortality.¹⁸ The MAST was for the most part abandoned, although some emergency medical systems still use it on patients with pelvic or lower-extremity fractures.

Pelvic binders have been commercialized by different companies along the same principles with only a few differences among them. Typically, a binder consists of a wide belt with a velcro that attaches the two ends of the binder (which can be cut to customize its length according to the patient’s body habitus). On the belt there is a “buckle pulley” mechanism. By pulling the strings the binder tightens and compression increases. The device is radiolucent, which allows radiographic imaging with no artifacts. The evidence on the effectiveness of pelvic binders is poor.^19,20 There are three major pitfalls related to its use. First, an inappropriately high placement of the binder can lead to excessive abdominal pressure and minimal pelvic stabilization. It is not uncommon to place the binder too high. Correctly, the binder must be centered around the greater trochanters and not over the iliac spines. Usually, it needs to be gently passed under the patient’s back and then pulled slightly lower and over the buttocks for proper placement. Second, indiscriminate pulling of the strings can lead to greater compression than necessary. The binder is frequently placed before the pelvic fracture is fully characterized by a CT scan or even by plain radiographs. Therefore, the initial step should involve only moderate tightening until the exact type of fracture is diagnosed. The pulley mechanism attached on the binder makes tightening very easy, and with minimal force an enthusiastic operator can squeeze the binder tight, producing on occasions more harm than good. Third, the binder may compromise the viability of skin, subcutaneous tissue, or even muscle if left in place for too long. A general guideline of a maximum 24-hour placement exists but obviously even this may be too long after a tight application of the binder.²¹ The health care providers should understand that the binder is only an imperfect and temporary tool for bleeding control. Definitive pelvic reduction and cessation of hemorrhage should be planned immediately in order to minimize the need for a binder.

A bed sheet is frequently used as an immediately available and inexpensive way to wrap the pelvis.²² The edges of the sheet are tied together and around a stick, which can be turned to tighten the sheet and apply the desired degree of compression (Fig. 35-8).

External Fixation

External fixation has been popularized as a rapid means of controlling bleeding. In a few institutions this can be accomplished in the emergency room but in most centers the patients are transferred in the operating room. A number of clamps and devices have been used to provide external fixation. The C-clamp was designed for easy placement in the emergency room in the presence of posterior pelvic fracture.²³ As opposed to other fixators, it is easy to assemble and apply. Its crossbar rotates around the fixation pins, which are anchored in the cancellous bone in both acetabula. The rotation of the clamp allows other procedures in the abdomen or pelvis to be offered without difficulty. The pins can be placed more anteriorly or posteriorly according to the location of the pelvic fracture and the need to reduce them. It is clearly a temporary method, which needs to be replaced later with either a proper pelvic frame or internal fixation. The C-clamp has been used more frequently in European than American trauma centers, which typically prefer a frame placed in the operating room.

Early external fixation stabilizes the fractured elements, decreases the pelvic volume, and allows clot to form. There is a variety of external fixators. The early systems used small pins and heavy bars, whereas the newer systems are more compact, easy to adjust, and with larger pins. The standard placement of pins is in the superior iliac crest above the superior anterior iliac spine. Lower placement of the pins is also acceptable and can improve the access to the abdominal cavity. In certain designs more than one pin are placed on each side. Pins can be placed by an open or percutaneous technique. All single bar systems require two pins in each hemipelvis, whereas the frames require three pins on each side, except the Pittsburgh system that requires two clusters of two pins in each hemipelvis. In most cases of a true unstable pelvis, external fixators remain a temporary device, which bridges the period to definitive internal fixation. In the supine position, external fixation provides adequate stability. In the standing position the vertical load is usually greater than the capacity of the external fixator to resist these forces. Dislocation of fractured elements can happen, particularly at the sacroiliac complex.²⁴

After placement of the frame, reduction of the pelvic fracture is done by applying opposite forces to the ones that created the fracture. Open-book fractures are corrected by internal rotation of the pins, whereas LC fractures are reduced by external rotation. Vertical shear fractures required skeletal traction by placement of a femoral pin and are the ones least likely to be adequately reduced and stabilized by external fixation.²⁵

If not converted to internal fixation, external fixators usually stay for 6–12 weeks. The most common complication is infection at the pin sites, ranging from mild to severe. Appropriate sterile technique during pin placement and proper care of the pin sites is essential to avoid infection. If the pins become infected or loose, they must be removed and replaced. Other complications are typically associated with placement and include injury to the lateral femoral cutaneous nerve or other neurovascular structures.

In general, it seems that external fixation should be considered in two stages, an early resuscitative and a later definitive stage. In the early stage the fixator is placed to stabilize the fracture and help control the bleeding. At a later stage a decision must be made about the long-term effectiveness of the external frame versus the need to convert to internal fixation. LC fractures are likely to respond to external fixation as the only method, if reduction is satisfactory. Vertical shear fractures are unlikely to be managed without definitive internal fixation.²⁶ Each patient must be carefully assessed to balance the therapeutic choices of fixing the fracture while maintaining hemodynamic stability and inflicting the minimum physiologic insult during the initial critical hours after trauma.

Angiographic Embolization

Pelvic ring fracture producing hemodynamic instability is one of the most common indications for angiographic embolization. The ability to control the bleeding by minimally invasive techniques and without the need for an operation, which is routinely unsatisfactory, is very appealing. However, the appeal is hampered by the unavailability of interventional radiology teams around the clock, the poor monitoring available in an angiography suite, and the long times spent on the angiography table. All three reasons have ceased to exist in modern trauma centers.

Interventional radiology teams are now immediately available with short notice in most level 1 trauma centers. In our hospital the team is in house until late at night and expected to be assembled within 40 minutes after that. Monitoring and resuscitation in the angiography suite should be no different in a level 1 trauma center than it is in the operating room. High-rate fluid infusion devices, noninvasive hemodynamic monitoring, mechanical ventilatory support, arterial blood gas assessments, blood transfusions, and aggressive resuscitation efforts should take place during angiography. The surgical team should be present throughout the procedure, exactly as it would be throughout an operation. An anesthesiologist and/or intensivist should be called according to the circumstances. Critical care nurses should participate in tasks with which radiology nurses are not familiar. Emergency angiography for bleeding control is not much different than an emergency laparotomy for the same reason. Shifting the care of the patient from the trauma team to the interventional radiologist during angiography is inappropriate. In our hospital the trauma team, including anesthesiology and critical care nursing when required, remains responsible for the monitoring and resuscitation of the trauma patient in the angiography suite during the emergency interventions for bleeding control. The concept of time spent for embolization is also important and will be discussed later.

The first challenge for the clinician is to identify the correct indications for angiography. Approximately one-fourth of the angiographies performed find no direct or indirect evidence of bleeding,²⁷ and the risk of an unnecessary transfer to the radiology suite could have been avoided in favor of a direct transfer to the intensive care unit. However, there are no controlled studies in the present literature and the precise indications are unknown. In 97 patients with pelvic fractures retrospectively reviewed no factors predicted a positive angiogram with sufficient likelihood.²⁷ Mechanism of trauma, injury severity, hemodynamic presentation, associated injuries, and hemodynamic presentation were similar between patients with and without radiographic evidence of pelvic bleeding. In a later prospective study by the same group, 65 patients with pelvic fractures were included in the study total of 100 consecutive patients evaluated by angiography for bleeding.²⁸ Three independent predictors of bleeding were identified: age older than 55 years, absence of long-bone fractures (indicating that the pelvis was the main source for bleeding), and emergent angiography (indicating that semiacute interventions had a lower likelihood to identify bleeding). The predictive effect of age was confirmed by another prospective observational study.²⁹ Ninety-four percent of patients older than 60 years of age had a positive angiogram as opposed to 52% of younger patients. The authors recommended that angiographic embolization is offered liberally to pelvic fracture patients over 60 years old.

Pelvic fracture pattern is considered a major predictor of bleeding. Traditionally, three types of PI are considered to be associated with hemorrhage: pubic symphysis diastasis of more than 2.5 cm, bilateral superior/inferior pubic rami fractures (butterfly), and posterior fractures (especially of the vertical shear variety).³⁰ However, there is evidence that even anterior fractures can produce bleeding,²⁷ particularly in older patients or those receiving anticoagulants. The presence of contrast extravasation on pelvic CT scan has also been widely used as a predictor of a positive angiogram.^31,32 It is suggested that the sensitivity and specificity of a “contrast blush” on CT to identify bleeding that requires embolization is 84% and 85%, respectively, with an overall accuracy of 90%.³² However, our experience has been that the new-generation CT scanners are highly sensitive and—in combination with precise IV contrast infusion protocols—may pick up small bleeds that are potentially self-limited without further intervention. Therefore, the mere presence of contrast extravasation on CT is not an immediate indication for angiography in our institution. We consider contrast extravasation a crucial element of the constellation of symptoms, signs, and findings of PI and consider it in the context of the entire clinical picture. A patient who is hemodynamically labile and has a contrast blush is emergently transferred to the angiography suite. A patient with a contrast blush, who is hemodynamically stable, does not usually receive a preemptive angiogram but is rather placed under close observation. In a study of 296 patients with pelvic fractures, 40% were found to have extravasation on CT but only half eventually required some form of pelvic hemorrhage control.³³ Similarly, the size of pelvic hematoma cannot be used as an isolated indication for angiography.³⁴

Interventional radiologists typically seek to identify the precise site of bleeding and control it with coils. This requires subselective intubation of internal iliac artery branches, time, and larger doses of intravenous contrast. For true trauma emergencies the interventional radiologist should be in a different mindset. In alignment with surgical damage control principles, damage control angiography should be offered. The procedure should be rapid, effective, and temporary. Bilateral internal iliac artery embolization embraces these principles. The interventional radiologist does not consume time maneuvering small catheters into small arterial branches. The bleeding is controlled by truncating all the branches of the internal iliac arteries by a temporary agent, such as gelatine sponge particles (Fig. 35-9). There are at least three reasons for performing bilateral internal iliac artery embolization: (1) at the time of embolization, the patient is often in shock and profoundly vasoconstricted. This prevents intravenous contrast extravasation during angiography and offers a misleading impression of bleeding control. Once the patient is resuscitated and vasoconstriction is reversed, bleeding may ensue. Blockage of all the branches of the internal iliac arteries prevents this problem. (2) The pelvic vascular network is so extensive that a bleeder may be fed reversely from the contralateral side. Embolizing only the unilateral internal iliac artery may not offer effective bleeding control (Fig. 35-10). (3) Some bleeders are right in the center and it is very difficult to discern if they are supplied by the right or the left arterial system. Embolizing both is the only way to control the bleeding (Fig. 35-11).

The safety of bilateral internal iliac artery embolization has been shown in a study of 30 consecutive patients who received the procedure with no major complications.³⁵ It seems that the extensive vascular supply of the pelvis ensures survival of pelvic tissues and organs during the few days of gelfoam embolization and until the arteries recanalize (Fig. 35-12). Gelfoam pledgets are usually cut to a size not smaller than 2 mm to prevent migration to smaller vessels and allow baseline collateral circulation. Despite isolated reports of serious complications with bilateral embolization for cancer,^36,37 such as colon necrosis, perineal wound sepsis, or avascular necrosis of the femoral head, our experience over the last 15 years has been very encouraging and without any significant complications. In a case-matched study of similar male pelvic fracture patients with and without bilateral iliac artery embolization, the incidence of sexual dysfunction 1–2 years after the injury was high but not different between the two groups.³⁸ Although major pelvic fractures affected sexual function, the addition of temporary embolization of both internal iliac arteries did not worsen the outcome. The authors assumed that, if this delicate function was not affected by embolization, it was unlikely that any other pelvic organ would suffer major long-term consequences.

Failure of embolization occurs in approximately 15% of the patients and is typically associated with coagulopathy.^39,40 In such patients the thrombogenic potential of the injected gelatin material may not be fully realized and vessels may not be effectively blocked, showing near-full recanalization within only hours of seemingly effective initial embolization. Superselective embolization is associated with a higher risk of rebleeding. Patients who continue to require blood transfusions within 72 hours after embolization should be taken back to the angiography suite, as repeat embolization is typically successful.

Preperitoneal Pelvic Packing

Packing has been an important part of damage control operations for severe abdominal injuries. For the pelvis, packing has been an ineffective method of bleeding control because the incision of the peritoneum to place the packs releases the tamponade. Furthermore, the open funnel that the pelvis presents does not allow for the packs to remain in place and exercise a hemostatic effect by compression; they rather float free back toward the abdomen.

Even if pelvic packing has not been popular in the United States, European trauma surgeons have used it more liberally. Ertel et al⁴¹ from Switzerland showed excellent bleeding control after major pelvic fractures using a combination of packing and external fixation by C-clamp. It is not clear which of the two techniques was primarily responsible for the outcomes. Recently, pelvic packing was reintroduced in the United States by the Denver trauma group.⁴² Their technique of preperitoneal pelvic packing addressed the previous problems of pack displacement and tamponade disturbance. By placing the packs behind the peritoneum through a separate low midline or suprapubic vertical incision, the peritoneal tamponade is not disturbed and the packs cannot float back toward the abdominal cavity. The authors have described the technique, which involves the opening of the fascia, retraction of the recti muscles laterally, and placement of approximately three packs on each side of the bladder deep into the pelvis. Attention is paid at all times to not open the peritoneum. For this reason, if a laparotomy is performed, the incision should be limited to the upper margin of the pelvic hematoma and not below that. Preperitoneal pelvic packing is then performed through a separate incision (Fig. 35-13). In our practice we have found the technique to be lifesaving in patients who are frankly unstable and cannot tolerate transport to the angiography suite. In these patients, the pelvic hematoma is typically very large and more than six packs may be needed to effectively compress all the bleeding sites. One needs to remember that the bleeding typically originates in the posterior pelvis and therefore, the packs should be placed deep into the pelvis and pressed against the sacrum. Given that the preperitoneal pelvis is not an open cavity, it is not an unusual pitfall to put the packs in a relatively superficial plane, failing to produce adequate compression against the bleeding vessels.

In a study of 28 patients receiving preperitoneal pelvic packing by the Denver trauma group, 21 (75%) survived. Only 14% of the patients had postoperative angiographic embolization.⁴² In a similar study by a Norwegian group 13 of 18 patients (72%) with packing survived but postoperative angiographic embolization was used in 80% of the patients.⁴³ In a follow-up study from Denver, 75 patients who received preperitoneal pelvic packing and external fixation were reviewed. Hemorrhage control was successful in most patients and angiographic embolization was offered only in a minority who required additional interventions to control the bleeding.⁴⁴ One should consider these three procedures (preperitoneal pelvic packing, external fixation, angiographic embolization) complementary rather than competing.⁴⁵ All of them can be offered on the same patient. We consider angiographic embolization as the preferred method of controlling pelvic bleeding for most patients. However, preperitoneal pelvic packing provides a useful alternative in the following circumstances if (1) there is no angiographic support, as it may happen in non-level 1 trauma centers; (2) there is angiographic support but the team cannot assemble expeditiously; (3) there is profound hemodynamic instability, which makes even mild delays unacceptable and calls for rapid packing in a ready operating room. Following packing, angiographic embolization should still be strongly considered.

Unstable and bleeding pelvic ring fractures are usually managed by a staged repair, which includes a pelvic binder initially, external fixation shortly after that, and internal fixation as the final step to reconstruction. The details of the surgical approach for definitive internal fixation of the pelvis are beyond the scope of this chapter and will not be discussed. External fixation can serve as definitive therapy, particularly in anterior pelvic ring fractures. It does not offer adequate stability in posterior fractures, particularly in the vertical axis. External fixation is appealing as a long-term solution because it avoids the risks of open operation but the reduction needs to be precise. If a reduction to less than 1 cm of initial displacement is not maintained throughout the period of healing, then 80% of the patients require chronic analgesics compared with almost none with precise reduction.⁴⁶ However, the complications rise as time progresses, and pin infection develops in 50% of definitive fixators, as opposed to 13% of temporary fixators.⁴⁷ The most common cause for replacing an external fixator is aseptic pin loosening. Approximately 10% of patients require replacing external with internal fixation as definitive treatment. For APC-II injuries a plate across the pubic symphysis may be enough, as the posterior pelvic stability is maintained by the unaffected strong posterior sacroiliac ligaments.

APC-III and most LC-II and vertical shear fractures typically require posterior stabilization by internal fixation. According to the specific type of fracture, sacroiliac screws (placed openly or percutaneously), special LC screws, or plates should be used. The complications of internal fixation are many and range from bleeding to injury of nerves, devascularization of muscle, infection, suboptimal reduction, and chronic pain.

Equally important to the surgical technique is the timing of internal fixation. The term “damage control orthopedics” was introduced to denote that at the early stages fracture fixation should be minimized to the least necessary, followed by definitive repair when the patient’s physiologic status allows it.^48,49 Early stabilization with later fixation is associated with lower levels of inflammatory cytokines and better outcomes compared with immediate fixation. The optimal time for definitive intervention is unclear and will probably vary from patient to patient. It has been suggested that clinical markers (such as the Systemic Inflammatory Response Score) or laboratory values (such as interleukin-6) can be monitored to decide about timing.⁵⁰ If the markers are on the rise, the inflammatory response is still rampant and a second hit may be detrimental. If the markers are decreasing or normal, definitive fixation is advisable.

Major pelvic fractures are commonly associated with intra- and extra-abdominal injuries. Closed head injury occurs in 51%, long-bone fractures in 48%, and thoracic injury in 20% of the patients. Among the extra-abdominal injuries the association with thoracic aortic injury is of particular importance and ranges between 1.4 and 5.9% among all patients with pelvic fractures.^51,52 The incidences of associated solid and hollow intra-abdominal organs injuries have been reported as 11% and 4.5%, respectively, and diaphragmatic injuries occur in 2% of pelvic fractures.⁵² All these associations point out to the complexity of diagnosing all the injuries and choosing the correct therapy. A patient with a major pelvic fracture will usually have—at least lower—abdominal tenderness and hemodynamic fluctuations. The decision to explore or avoid the abdominal cavity is often hard as clinical examination, FAST, diagnostic peritoneal aspiration, or even CT scan may give equivocal information. The presence of a central neurologic injury will only confuse the picture further. The suggested algorithm in Fig. 35-15 can serve as a guideline for the management of major pelvic fractures, although each patient is unique and requires individualized decisions.

Probably, the most notable association is between pelvic fracture and bladder or urethral injuries. The physical proximity of these injuries results in an injury rate of 6%, which increases by nearly fivefold with male gender and severe fractures. The majority of bladder ruptures (80%) are extraperitoneal. They can be managed by simple Foley catheter drainage for 10–14 days. Intraperitoneal injuries require a laparotomy and direct repair. Urethral injuries are common and almost exclusively in males.⁵³ Straddle injuries, typically producing bilateral pubic rami fractures, are associated with urethral injuries. The presence of a perineal hematoma, blood at the urethral meatus, or a high-riding prostate should alert the clinician about a urethral injury. A retrograde urethrogram should be performed before inserting a Foley catheter. On selected occasions, in which time is of the essence, advancing a Foley catheter without first performing a retrograde urethrogram is an acceptable alternative. It should be done by a senior person and with extreme care to stop and withdraw in the presence of any resistance. If a Foley catheter cannot be inserted because of a urethral injury, a suprapubic catheter is appropriate. Urethral injuries are usually repaired at a later stage after the inflammation has subsided but there are reports of successful aggressive early management. Obviously, these decisions will be made jointly by a urologist and the trauma surgeon.

A combination of open wounds with pelvic ring injuries produces an extremely challenging situation, as bleeding and ongoing contamination are typically profound and death rates are usually in excess of 20% and up to 50%. Lacerations of the perineum are much more difficult to manage than anterior lacerations. These two types of open pelvic fractures should not be described as the same entity because the management should be different according to the location and extent of the skin laceration.

The priorities in management of major open pelvic fractures are not much different than the management of any other devastating injury and include—in order of priority—the control of bleeding, control of contamination, and definitive fixation. Control of bleeding in open pelvic fractures involves packing through the laceration, application of a pelvic binder, angiographic embolization, and external fixation. Preperitoneal pelvic packing, as it was described above, may not be effective because the tamponade of the retroperitoneal pelvic space is already released to the external environment. There is a debate about the need for colostomy to control contamination. Many authors believe that a diverting colostomy should be routinely performed as an integral part of the surgical management of an open pelvic fracture (Fig. 35-14). In a study of 39 patients with open pelvic fractures the mortality was 26% and predicted by fracture instability and rectal injury. The authors suggested that early colostomy is important to survival.⁵⁴ In another study of 44 patients, 23 were managed with a diverting colostomy and 21 without it. Even if the patients with colostomy were more severely injured, they had a lower 30-day mortality. Pelvic sepsis and anastomotic complications contributed to mortality in the no-colostomy group, and the authors recommended the liberal use of colostomy.⁵⁵ However, a systematic analysis of the literature showed that there were no differences in outcome between patients with and those without a colostomy.⁵⁶ Nevertheless, the authors recognized that the evidence was of poor quality and solid conclusions could not be made, and called for prospective randomized studies, a rather unlikely goal, given the low incidence of these injuries. A midway solution was described on 18 patients, of whom 5 had a colostomy because of perineal wounds, whereas 13 with anterior wounds were not subjected to this procedure.⁵⁷ No patient without a colostomy developed pelvic sepsis, and the authors recommended a selective approach. This exactly is our approach too. Patients with rectal wounds or with wounds in immediate proximity to the anus usually receive a diverting colostomy. Patients with more distal wounds are usually managed without fecal diversion. Debridement of ischemic tissue is an important part of the management. Despite all strategies, the mortality of open pelvic fractures remains very high, even in the modern era, even in expert hands. The Grady Memorial Hospital group described 44 such patients with a mortality of 45%.⁵⁸ The presence of bleeding and need for angiographic embolization was associated with a grim prognosis. Late pelvic sepsis developed in five patients and three of them died. It, therefore, seems that primarily bleeding and secondarily sepsis continue to claim a heavy toll on the lives of patients with this devastating injury.

Neurologic injury is a characteristic disorder after pelvic trauma with serious long-term implications. In an electrodiagnostic study of 78 patients with pelvic trauma and lower—extremity neurologic symptoms, the incidence of gait instability and neuropathic pain was high.⁵⁹ As already discussed, sexual dysfunction remains a major problem in approximately two-thirds of male patients with major pelvic fractures.³⁸ Sensory impairments were noted in 91% of the patients with unstable sacral fractures 1 year after the injury.⁶⁰ Impaired gait was recorded in 63% and bladder, bowel, or sexual impairments in 59%. In a questionnaire study of 24 women with a Tile B or C pelvic fracture and a median age of 24 years, 16 reported de novo pelvic dysfunction.⁶¹ Bladder symptoms were present in 12, bowel problems in 11, and sexual dysfunction in 7. Malunion of fractures can produce leg-length discrepancies, creating gait instability and pain. It is, therefore, obvious that even with optimal management, severe pelvic fractures are associated with long-term sequelae. Pain and neurologic impairments are the most common problems that can compromise the quality of life.

Major pelvic fractures are associated with significant bleeding, complications, and mortality. A multidisciplinary approach is important. The diagnosis of major pelvic bleed should be made in the trauma bay based on external clues of injury to the pelvis, physical examination indicating pelvic ring instability, and exclusion of other potential sources. The CT scan is currently the most useful test to characterize the fractures, detect hematomas and active contrast extravasation, and plan further treatment. In the presence of bleeding, angiographic embolization is indicated and should be done in most cases along the principles of damage control angiography. Pelvic binding in the emergency room and external fixation are important interventions to reduce bleeding, pain, and ongoing injury. Internal fixation is best left for a later stage. Preperitoneal pelvic packing can be a lifesaving maneuver for those patients who are too unstable to travel to the angiography suite or in these hospitals that do not have easy access to angiography. A general algorithm is provided (Fig. 35-15) but the exact sequence of interventions should be individualized to the particular complexities of these challenging patients.