Aberrant Obturator Artery Is a Common Arterial Variant That May Be a Source of Unidentified Hemorrhage in Pelvic Fracture Patients

Analysis of Variation in the Origin of the Obturator Artery in Midwestern American Donor Bodies

The obturator artery (OA) is typically a branch of the anterior division of the internal iliac artery. However, an aberrant obturator artery origin may lead to clinical complications. Because of its location in the pelvic cavity, the OA is at high risk of injury or laceration during a variety of pelvic surgeries. Regarding this, variations in the origins of the OA may result in bleeding that can often be overlooked, rendering treatment ineffective. Our study aimed to assess the origins and course of the OA in Midwestern American donor bodies. Sixty-two donor bodies were obtained from the Gift of Body Donation Program at A.T. Still University's Kirksville College of Osteopathic Medicine. The origin of each OA was documented and photographed. The OA was identified by observing the vessel's passage through the obturator foramen. Of 132 OAs studied, 72 (54.5%) had an aberrant OA. Further, 22 (16.7%) had an aberrant OA origin from the inferior epigastric artery, 20 (15.2%) had an aberrant OA origin from the posterior division of the internal iliac artery, 22 (16.7%) had an aberrant OA origin from dual origins of the anterior division of the internal iliac artery and the inferior epigastric artery, and eight (6.1%) had other aberrant OA origins. Overall, our results indicated anatomical variations are common in the origins and course of the OA. These data highlight the importance of considering variations in the OA and the prevalence of those variations during vascular and orthopedic procedures.

Frequency and Clinical Review of the Aberrant Obturator Artery: A Cadaveric Study

The occurrence of an aberrant obturator artery is common in human anatomy. Detailed knowledge of this anatomical variation is important for the outcome of pelvic and groin surgeries requiring appropriate ligation. Familiarity with the occurrence of an aberrant obturator artery is equally important for instructors teaching pelvic anatomy to students. Case studies highlighting this vascular variation provide anatomical instructors and surgeons with accurate information on how to identify such variants and their prevalence. Seven out of eighteen individuals studied (38.9%) exhibited an aberrant obturator artery, with two of those individuals presenting with bilateral aberrant obturator arteries (11.1%). Six of these individuals had an aberrant obturator artery that originated from the deep inferior epigastric artery (33.3%). One individual had an aberrant obturator artery that originated directly from the external iliac artery (5.6%).

Multidetector CT in Vascular Injuries Resulting from Pelvic Fractures: A Primer for Diagnostic Radiologists

Pelvic vascular injuries are typically caused by high-energy trauma. The majority of these injuries are caused by motor vehicle collisions, and the rest are caused by falls and industrial or crush injuries. Pelvic vascular injuries are frequently associated with pelvic ring disruption and have a high mortality rate due to shock as a result of pelvic bleeding. Morbidity and mortality resulting from pelvic vascular injury are due to pelvic hemorrhage and resultant exsanguination, which is potentially treatable and reversible if it is diagnosed early with multidetector CT and treated promptly. The pelvic bleeding source can be arterial, venous, or osseous, and differentiating an arterial (high-pressure) bleed from a venous-osseous (low-pressure) bleed is of paramount importance in stratification for treatment. Low-pressure venous and osseous bleeds are initially treated with a pelvic binder or external fixation, while high-pressure arterial bleeds require angioembolization or surgical pelvic packing. Definitive treatment of the pelvic ring disruption includes open or closed reduction and internal fixation. Multidetector CT is important in the trauma setting to assess and characterize pelvic vascular injuries with multiphasic acquisition in the arterial and venous phases, which allows differentiation of the common vascular injury patterns. This article reviews the anatomy of the pelvic vessels and the pelvic vascular territory; discusses the multidetector CT protocols used in diagnosis and characterization of pelvic vascular injury; and describes the spectrum of pelvic vascular injuries, the differentiation of common injury patterns, mimics, and imaging pitfalls. Online supplemental material is available for this article. ^©RSNA, 2019 See discussion on this article by Dreizin.

Where and what arteries are most likely injured with pelvic fractures?: The Influence of Localization, Shape, and Fracture Dislocation on the Arterial Injury During Pelvic Fractures

Blood vessels passing through pelvic region come into intimate contact with pelvic bone and can be injured by the sharp edges of the dislocated fracture fragments. The aim of the study was to evaluate the influence of localization, shape, and dislocation of individual pelvic ring bones' fractures on arterial injuries. The study group consisted of 474 patients enrolled in a 1-year prospective multicenter study. The pattern of pelvic fracture lines was characterized and recorded on a planar diagram of the subjected side of the pelvis. The diagram was subdivided into 11 designated areas. Frequency of injury at each 11 areas was recorded. The course of individual arteries in the 11 areas was also recorded in relation to each type of pelvic fractures. Out of the 474 investigated patients, the highest proportion of fractures occurred in the areas of the superior (62%) and inferior (59%) ramus of the pubis as well as in the lateral part of the sacrum (19%). These locations can be associated with injuries of the external iliac, obturator, internal iliac, and aberrant obturator arteries. The highest risk of arterial injuries was associated with vertically displaced fractures in the middle part of the superior and inferior pubic rami, along the ischial ramus, in the apex of the greater sciatic notch and in the vicinity of the ventral part of the sacroiliac joint, where the artery runs at a distance of less than 1 cm from the bone. Clin. Anat. 32:682-688, 2019. © 2019 Wiley Periodicals, Inc.

Penetrating Obturator Artery Injury after Gunshot Wounds: A Successful Multidisciplinary Trauma Team Approach to a Potentially Lethal Injury

Obturator artery injury (OAI) from pelvic gunshot wounds (GSW) is a rarely reported condition. Hemorrhages from pelvic trauma (PT) are mostly venous. Arterial hemorrhages represent about 10-20% of PTs. When arterial hemorrhages from PT occur, they are a severe and deadly complication often causing significant hemodynamic instability and eventual shock.

A 23-year-old male presented to our emergency service via a private vehicle with multiple gunshot wounds to both thighs and to the lower back, resulted in rectal and obturator artery (OA) injuries. The patient underwent a successful coil-embolization of the right OA.

Given the density of structures within the pelvis, patients who sustain gunshot wounds to the pelvic region are at high risk for injury to the small bowel, sigmoid colon, rectum, bladder, and/or vascular structures. While bleeding is the major cause of early mortality in PT, rectal injuries carry the highest mortality due to visceral injuries. A high clinical index of suspicion is needed to diagnose an iliac artery injury or injury to its branches. Prompt computed tomographic angiogram (CTA) and embolization of the OA is the best method to control and stop the bleeding and improve the mortality outcome.

Clinicians caring for patients presenting with pelvic gunshot wounds should pay attention to the delayed presentation of internal hemorrhage from the OAs. A multidisciplinary team approach is crucial in the successful management of penetrating injuries to the obturator artery.

A new concept and classification of corona mortis and its clinical significance

PURPOSE

The obturator artery and its accessory (aberrant) arising from different origins and crossing the pubic rami are vascular variations. The internal iliac artery usually provides the obturator artery which may communicates with the external iliac artery through either the accessory obturator or inferior epigastric artery. A collateral circulation between the external and internal iliac system is known as corona mortis. The aim of current study is to provide sufficient data of vascular variability crossing the pubic rami for clinical field.

METHODS

Present study includes 208 hemipelvises dissected in the Institution of Anatomy, Medical University of Graz. During dissection, the obturator artery and its accessory crossing the superior rami of pubic bone were found to have different origins.

RESULTS

The obturator artery arising from the external iliac artery and from the femoral artery accounts for 9.8% and 1.1% respectively. Therefore, it passes over the superior pubic rami in 10.9%. Further, the accessory (aberrant) artery arises only from the femoral artery in 1.1%. In present study, the vascular variation crossing the superior pubic rami with or without collateral circulation between external and internal iliac system referred as corona mortis is addressed. This study includes new classification of obturator and accessory obturator arteries as well as the corona mortis. It includes a comparison of corona mortis incidence in Austria population and other populations. The corona mortis found to be in 12% of Austrian population.

CONCLUSION

A great attention of clinicians, radiologists, surgeons, orthopedic surgeons, obstetricians and gynecologists has to be considered before pubic surgical procedures such as internal fixation of pubic fracture, an inguinal hernia repair. Further, traumatic pubic rami fracture may lead to massive hemor- rhage due to laceration of the obturator artery.

Diagnosis and treatment of rare complications of pelvic fractures

PURPOSE

To enhance the awareness of rare complications of pelvic fracture and describe the correct diagnosis and effective treatment.

METHODS

A total of 188 cases of pelvic fractures were retrospectively reviewed, and four patients who suffered from four types of rare pelvic fracture complications were described, namely ureteral obstruction caused by retroperitoneal hematoma-induced abdominal compartment syndrome (ACS), bowel entrapment, external iliac artery injury, and open scrotal sac injury.

RESULTS

We demonstrated that combined measures should be employed to prevent the occurrence of ACS following major pelvic fractures. Ureteral catheter support may be a good option at an early stage when ACS occurred. Contrasted computed tomography examination and sufficient awareness are keys to a correct diagnosis of bowel entrapment following pelvic fractures. Recognition of risk factors, early diagnosis, and prompt treatment of suspected injury of the external iliac artery are keys to patient survival and to avoid limb loss. Scrotal and/or testicular injury complicated by pelvic fractures should be carefully treated to maintain normal gonad function. Additionally, establishment of a sophisticated trauma care system and multi-disciplinary coordination are important for correct diagnosis and treat- ment of rare complications in pelvic fractures.

CONCLUSIONS

Rare complications of pelvic fractures are difficult to diagnose and negatively impact outcome. Recognition of risk factors and sufficient awareness are essential for correct diagnosis and prompt treatment.

Clinical importance of a star shaped branch of internal iliac artery and unusual branches of an abnormal obturator artery: rare vascular variations

The internal iliac artery (IIA) is one of the branches of the common iliac artery and supplies the pelvic viscera, the musculoskeletal part of the pelvis, the gluteal region, the medial thigh region and the perineum. During routine cadaveric dissection of a male cadaver for undergraduate Medical students, we observed variation in the course and branching pattern of the left IIA. The artery gave rise to two common trunks and then to the middle rectal artery, inferior vesicle artery and superior vesicle artery. The first, slightly larger, common trunk gave rise to an unnamed artery, the lateral sacral artery and the superior gluteal artery. The second, smaller, common trunk entered the gluteal region through the greater sciatic foramen, below the piriformis muscle and presented a stellate branching pattern deep to the gluteus maximus muscle. Two of the arteries forming the stellate pattern were the internal pudendal artery and the inferior gluteal artery. The other two were muscular branches.

WSES position paper on vascular emergency surgery

Trauma, both blunt and penetrating, is extremely common worldwide, as trauma to major vessels. The management of these patients requires specialized surgical skills and techniques of the trauma surgeon. Furthermore few other surgical emergencies require immediate diagnosis and treatment like a ruptured abdominal aortic aneurysm (rAAA). Mortality of patients with a rAAA reaches 85 %, with more than half dying before reaching the hospital. These are acute events demanding immediate intervention to save life and limb and precluding any attempt at transfer or referral. It is the purpose of this position paper to discuss neck, chest, extremities and abdominal trauma, bringing to light recent evidence based data as well as expert opinions; besides, in this paper we present a review of the recent literature on rAAA and we discuss the rationale for transfer to referral center, the role of preoperative imaging and the pros and cons of Endoluminal repair of rAAA (REVAR) versus Open Repair (OR).

Multiple variations in the pelvic vasculature - a case report

A thorough knowledge of possible variations of pelvic vasculature is very useful for surgeons, gynaecologists, radiologists, urologists and orthopaedic surgeons. We report multiple vascular variations in the left half of the pelvis of an adult male cadaver. Iliolumbar artery arose from the main trunk of the internal iliac artery. Posterior division of the internal iliac artery gave two lateral sacral arteries and a superior gluteal artery. The anterior division of the internal iliac artery gave origin to superior vesical, inferior vesical, inferior gluteal and internal pudendal arteries. The internal pudendal artery gave origin to a common trunk before leaving the pelvis. The common trunk divided into middle rectal artery and deep artery of the penis. The obturator artery took origin from the inferior epigastric artery and descended downward to the pelvis and left the pelvis by passing through the obturator foramen. Most of the other veins accompanying the arteries joined to form a plexus on the superior surface of the pelvic diaphragm. This plexus condensed to form anterior and posterior divisions of the internal iliac vein. Apart from this, the posterior part of the plexus drained directly into the common iliac vein through a large unnamed vein.

Emergency computed tomography for acute pelvic trauma: where is the bleeder?

Contrast medium extravasation at computed tomography (CT) is an accurate indicator of active haemorrhage in pelvic trauma. When this is present, potentially lifesaving surgical or endovascular treatment should be considered. Identification of the site or territory of haemorrhage is helpful for the interventional radiologist as it allows for focused angiographic evaluation and expedites haemostatic angio-embolisation. Even with thin-section arterial phase CT, tracing the bleeding vessel is not always possible and is often time consuming. We introduce a technique for predicting the bleeding vessel based on knowledge of the cross-sectional anatomical territory of the vessel as an alternative to tracing the vessel's course. Several case examples with digital subtraction angiography (DSA) correlation will be provided.

Frequency of external iliac artery branch injury in blunt trauma: improved detection with selective external iliac angiography

PURPOSE

To assess the utility of selective external iliac artery (EIA) angiography and the frequency of injury to branches of the EIA in cases of blunt pelvic trauma.

MATERIALS AND METHODS

A retrospective review of pelvic angiograms in 66 patients with blunt pelvic trauma was conducted over a 12-month period. Pelvic and femur fracture patterns were correlated to the presence of EIA injury. Pelvic arteriography was compared versus selective EIA angiography for the detection of arterial injury.

RESULTS

Fifty-four of 66 patients (82%) exhibited pelvic arterial injury or elicited enough suspicion for injury to warrant embolization. Internal iliac artery embolization was performed in 50 of 66 (76%). EIA branch injury was identified in 11 of 66 patients (17%), and 10 were successfully embolized. EIA branch vessel injury was identified more frequently when there was ipsilateral intertrochanteric fracture (P = .07) or ipsilateral ilium fracture (P = .07). The sensitivity of nonselective pelvic angiography in the detection of EIA branch vessel injury was 45%.

CONCLUSIONS

EIA branch injury occurs in a substantial fraction of patients with blunt pelvic trauma who undergo pelvic angiography. Selective EIA angiography should be considered in all patients undergoing pelvic angiography in this situation.

Management of traumatic hemipelvectomy: an institutional experience on four consecutive cases

BACKGROUND AND OBJECTIVE

The incidence of traumatic hemipelvectomy is rare, but it is a devastating injury. Recently, an increasing number of patients with traumatic hemipelvectomy are admitted to trauma centers alive due to improvements of the pre-hospital care. Successful management requires prompt recognition of the nature of this injury and meticulous surgical technique. We present our successful experiences on four cases of traumatic hemipelvectomy in the past nine years.

PATIENTS AND METHODS

Four cases with traumatic hemipelvectomy were admited to our hospital from June 21, 2002 to September 3, 2011. All injuries occurred due to vehicle accident and all patients were in a state of severe hypotension, with two of them having anal lacerations. These four cases were treated immediately with resuscitation, control of hemorrhage, early amputation, repeated debridement and closure of the wounds. An angiographic embolization was given to control hemorrhage in two of the cases preoperatively. One case underwent fecal diversion. Wound infection occurred in all of cases which was successfully controlled by repeated debridements, effective anti-biotic regimen, split-thickness skin grafts.

RESULTS

All four cases were saved successfully with well-healed wounds during follow up from 1 to 7 years. They were able to walk by themself using crutches.

CONCLUSION

Adhering to the surgery principles of damage control including appropriate resuscitation, hemorrhage control, coagulopathy correction and multiple debridements and closure of the wounds in reasonable period of time can save the life of cases suffering from severe pelvic ring injury.

Corona mortis: anatomical data and clinical considerations

BACKGROUND

Minimally invasive procedures, such as the TVT-Secur™, have been linked to injury to the corona mortis. Injury during the insertion of the TVT-Secur™ happens due to the vessel's position close to the place of the margin (25-30 mm from the symphysis pubis).

AIMS

Systematic description of the aberrant vessel anatomy so as to help gynaecologists determine the risk of peri- and postoperative complications during the TVT-Secur™ and related procedures.

METHODS

In a cadaver study, the lesser pelvis of ten female cadavers with venous or arterial coronae mortis was dissected. The origin, diameter and course of the aberrant vessels, as well as the distance from the symphysis pubis, were documented.

RESULTS

Arterial coronae mortis were found in eight hemipelvises. All vessels originated from the ipsilateral inferior epigastric artery and all crossed over the superior pubic rami. Average distance from the symphysis pubis was 52.4 mm. Average vessel diameter was 3 mm. Venous coronae mortis were identified in ten hemipelvises. Eight drained into the external iliac and four into the inferior epigastric artery. Nine vessels crossed over the superior pubic rami. Average distance from the symphysis pubis was 46.7 mm. Average vessel diameter was 3.13 mm.

CONCLUSION

Although individual variation makes direct contact with the vessel possible, in most cases there is a window of eight millimetres at least between the margin of the TVT-Secur™ and most aberrant veins. Possible aberrant arteries seem to lie even further.

Hemorrhage detection and segmentation in traumatic pelvic injuries

Automated hemorrhage detection and segmentation in traumatic pelvic injuries is vital for fast and accurate treatment decision making. Hemorrhage is the main cause of deaths in patients within first 24 hours after the injury. It is very time consuming for physicians to analyze all Computed Tomography (CT) images manually. As time is crucial in emergence medicine, analyzing medical images manually delays the decision-making process. Automated hemorrhage detection and segmentation can significantly help physicians to analyze these images and make fast and accurate decisions. Hemorrhage segmentation is a crucial step in the accurate diagnosis and treatment decision-making process. This paper presents a novel rule-based hemorrhage segmentation technique that utilizes pelvic anatomical information to segment hemorrhage accurately. An evaluation measure is used to quantify the accuracy of hemorrhage segmentation. The results show that the proposed method is able to segment hemorrhage very well, and the results are promising.