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.

The surgical neurovascular anatomy relating to partial and complete sacral and sacroiliac resections: a cadaveric, anatomic study.

PURPOSE: Pelvic and sacral surgeries are considered technically difficult due to the complex multidimensional anatomy and the presence of significant neurovascular structures. Knowledge of the key neurovascular anatomy is essential for safe and effective execution of partial and complete sacral resections. The goal of this anatomic, cadaveric study is to describe the pertinent neurovascular anatomy during these procedures. METHODS: Three embalmed human cadaveric specimens were used. Sacrectomies and sacroiliac joint resections were simulated and the structures at risk were identified. Both anterior and posterior approaches were evaluated. RESULTS: During sacroiliac joint resection, L5 nerve roots are at high risk for iatrogenic injury; the vasculatures at greatest risk are the common iliac vessels and internal iliac vessels with L5-S1 and S1-S2 high sacrectomies. Minor bleeding risk is associated with S2-S3 osteotomy because of the potential to damage superior gluteal vessels. S3-S4 osteotomy presents a low risk of bleeding. Adjacent nerve roots proximal to the resection level are at high risk during higher sacrectomies. CONCLUSIONS: Several sacrectomy techniques are available and selection often depends on the specific case and surgeon preference; nevertheless, anatomic knowledge is extremely important. Considering the highly variable anatomic relations of the vascular bundles, a preoperative evaluation with CT or MRI with vascular reconstruction may be helpful to decrease bleeding risk by preemptively binding the internal iliac vessels in cases where higher tumors are present. To decrease the risk of damaging nerve roots, it is recommended to perform the resection as close to the involved foramina as possible.

Power Doppler ultrasonography in the evaluation of infliximab treatment for sacroiliitis in patients with ankylosing spondylitis.

The aim of this study was to evaluate the feasibility of using power Doppler ultrasound (PDUS) to detect changes in the sacroiliac joint regions after infliximab (an anti-TNF-α blocker) treatment in active axial ankylosing spondylitis (AS) patients. A total of 110 sacroiliac joints in 55 patients with active AS were detected by PDUS before and after the infliximab treatment. The color flow signals inside the sacroiliac joints were observed, and the resistance index (RI) was measured. The clinical condition of the AS patients was improved compared with their condition before the infliximab treatment. Before the treatment, color flow signals were observed in 103 joints, and the mean RI value was 0.56 ± 0.06. Three months after the first infliximab treatment, color flow signals were observed in 50 joints, and the mean RI value was 0.87 ± 0.11. There were more blood flow signals in the sacroiliac joints before the infliximab treatment in patients with active AS (p < 0.01), and the mean RI value was higher after the infliximab treatment (p < 0.01). The blood flow signals in the sacroiliac joints became weaker or even disappeared and the RI values increased in patients with active sacroiliitis after infliximab treatment. This result shows that PDUS can be used in the follow-up of patients with axial AS.

Vascular risk reduction during anterior surgical approach sacroiliac joint plating.

INTRODUCTION: Open reduction and internal fixation of sacroiliac (SI) joint is often performed through an anterior approach. However, there were no studies to our knowledge which described the "at risk area" for injury to the nutrient artery as it relates to open reduction and internal fixation of the SI joint. The purpose of this study was to determine the "at risk area" for the nutrient artery during anterior surgical approaches to the SI joint and to define the safe location of the plate for SI joint fixation. MATERIALS AND METHODS: Six right and five left hemipelvises (three male and three female cadavers) were dissected with a mean age of 72 years (range, 51-90 years). Three bony landmarks including the pelvic brim, anterior SI joint line, and the anterior superior iliac spine (ASIS) were identified to quantify the measurements. Three different measurements were taken: from the nutrient foramen to the anterior SI joint line; from the nutrient foramen to the nearest point on the pelvic brim; from the nutrient foramen to ASIS using a flexible ruler with a 1mm base. RESULTS: The nutrient artery courses across the SI joint to enter into the nutrient foramen. Whilst exposing the internal surface of the SI joint, the nutrient foramen was identified at a mean distance of 88.1mm medial to ASIS, 20.1mm above the pelvic brim, and 20.1mm lateral to SI joint. The variability of the location of the nutrient foramen was identified and was located from 80mm to 95mm medial to the ASIS, 12mm to 25mm lateral to the SI joint, and 16mm to 30mm above the pelvic brim. CONCLUSION: Familiarity of the vasculature of the internal pelvis is of utmost importance for the surgeon when considering operative fixation of the anterior SI joint. We were able to identify the relation of the nutrient artery to the anatomic landmarks of the internal pelvis and to define the "at risk area" for the nutrient artery. We believe increased understanding of the anatomy of the nutrient artery will aid in the avoidance of vascular complications during internal fixation of the anterior SI joint.

Evaluation of complex appearance in vascularity of sacroiliac joint in ankylosing spondylitis by color Doppler ultrasonography.

To investigate the complex appearance of vascularity of sacroiliac joint (SIJ) in ankylosing spondylitis. Sixty-eight patients and 35 controls were included in the study. Blood flow was examined at the SIJ by using color Doppler ultrasonography (CDUS). The location of color flow signs and flow pattern were observed. Arteries do not present reversed phase in diastolic phase on pulse Doppler sonography, and if they were found inside and around the SIJ, the resistive index (RI) was measured. In active AS patients, the region of SIJ presented increased vascularization greater than those in inactive AS (P = 0.001) and the controls (P = 0.001). There are three different spectral Doppler tracings: arterial flow (RI < 1), arterial flow representing reversed phase in diastolic phase on spectral Doppler sonography and venous flow. Besides arterial flow signs, most of color flow signs presented venous flow in active AS. Significant increases in a number of venous flow signs in active AS cases (P < 0.001) were observed. In most cases, two or more different flow patterns presented in a region very close to the location of SIJ. In addition, a different vascularization was observed. Abnormal vascularization at the sacroiliac joints can be detected by CDUS. The vascularization in SIJ presented complex appearance, which increases the difficulties of CDUS examination. Venous blood flow in the assessment of active AS merits further study.

Feasibility of second-generation ultrasound contrast media in the detection of active sacroiliitis.

OBJECTIVE: To determine whether a recently available contrast-enhanced ultrasound (CEUS) technique using second-generation microbubbles allows for the detection of active sacroiliitis, and to measure CEUS enhancement depth at the dorsocaudal part of the sacroiliac (SI) joints in healthy volunteers compared with patients with sacroiliitis. METHODS: Forty-two consecutive patients (84 SI joints) presenting with a clinical diagnosis of sacroiliitis in 50 SI joints and 21 controls (42 SI joints) were investigated by CEUS using a standardized low mechanical index ultrasound protocol. Detected vascularity was used to retrospectively measure the enhancement depth in the dorsocaudal part of the SI joints. RESULTS: CEUS detected enhancement in all clinically active SI joints, showing an enhancement depth into the dorsal SI joint cleft of 18.5 mm (range 16-22.1), which was significantly higher compared with both inactive joints of patients (3.6 mm, range 0-12; P < 0.001) and healthy controls (3.1 mm, range 0-7.8; P < 0.001). All inactive joints were correctly classified based on a lack of deep enhancement in patients with sacroiliitis and controls (42 of 42, 100% sensitivity, 100% specificity; Cohen's kappa = 1). CONCLUSION: CEUS allowed the differentiation of active sacroiliitis from inactive SI joints, and proved to be a feasible method for the detection of vascularity in clinically active sacroiliitis by showing deep contrast enhancement into the SI joints not detectable in inactive joints of patients or controls. If this technique might add information to the earlier detection of sacroiliitis, it should be addressed in further studies.

Color and duplex Doppler sonography to detect sacroiliitis and spinal inflammation in ankylosing spondylitis. Can this method reveal response to anti-tumor necrosis factor therapy?

OBJECTIVE: To investigate the role of color and duplex Doppler ultrasound (CDDUS) in the detection of sacroiliac (SI) and spinal inflammation, as well as response to anti-tumor necrosis factor (TNF) therapy in patients with ankylosing spondylitis (AS). METHODS: We included 39 consecutive patients with AS followed at our center and 14 healthy controls. In the AS and control groups, blood vessels in SI joints and lumbar vertebral (LV) and thoracal vertebral (TV) paraspinal areas were investigated by CDDUS. When the artery was found, the resistive index (RI) was measured by CDDUS. Disease activity characteristics (ESR, CRP, BASDAI, and BASMI) were evaluated in patients with AS. In 11 patients for whom anti-TNF therapy was indicated, CDDUS measurements were performed before and on Week 12 of therapy. RESULTS: In patients with AS, RI values of SI joints and of LV and TV areas were lower than in controls (all p < or = 0.01). In AS patients with active disease according to BASDAI, RI values of TV (p = 0.0013) and LV (p = 0.027) were significantly lower than in the inactive group. In the group with active AS, SI RI was nonsignificantly lower (p = 0.16). After anti-TNF therapy, there were significant increases in mean SI RI (p = 0.028) and LV RI (p = 0.039), and a nonsignificant increase in TV RI (p > 0.05). CONCLUSION: CDDUS may be an alternative, less expensive, and easier method for detecting inflammation secondary to increased SI and spinal vascularization and in evaluating response to anti-TNF therapy in AS.

Anatomical consequences of "open-book" pelvic ring disruption: a cadaver experimental study.

UNLABELLED: "Open-book" pelvic fractures associate a diastasis and/or a fracture of the pubic rami with a posterior pelvic disruption of the sacro-iliac joint. These uni or bilateral lesions are potentially lethal mainly due to associated injuries and massive pelvic hemorrhage. The most frequently injured arteries are parietal branch of the commune, internal or external arteries because of their proximity to the bone, the sacro-iliac joint and the inferior ligaments of the pelvis. The pelvic bone dislocation and the increase of pelvic volume facilitate blood effusion. The aim of this study was to determine, on a cadaver fracture model, the direct anatomical consequences of "open-book" pelvic fracture on the ilio-lumbar pedicle and the pelvic cavity volume. MATERIALS AND METHODS: Bilateral open-book pelvic ring injuries were created in ten non-embalmed cadaver specimens by directly disrupting the pubic symphysis, the right and the left sacro-iliac joints. Pelvic volume was determined after total pelvic exenteration. Consequences of this fracture on vascular parietal network, nervous pelvic trunk and pelvic cavity volume were studied. RESULTS: The mean volume of the pelvic cavity after complete visceral exenteration was 872.5 cm(3) (extremes 580-756 cm(3)). The average increase of pelvic volume was 20.8% after 5 cm of pubic diastasis. In all cases, because of a transversal disposition of the ilio-lumbar pedicle with regard to the sacro-iliac joint, reproduction of the open-book fracture caused a venous dilaceration of the ilio-lumbar vein in 12 cases after 5 cm of pubic diastasis (12/20=60%). No arterial dilaceration was observed on the ilio-lumbar artery, but this artery was put in tension. CONCLUSION: Open-book fractures create an increase of pelvic volume that facilitates blood diffusion from parietal pelvic vascular network. Ilio-lumbar pedicle seems to be very vulnerable in this type of fracture because of its relations to the sacro-iliac joint and its transversal disposition with regard to this joint.

Duplex and color Doppler sonographic findings in active sacroiliitis.

OBJECTIVE: The aim of this study was to describe the duplex and color Doppler sonographic findings in active sacroiliitis. SUBJECTS AND METHODS: Forty-one joints in 21 patients with active sacroiliitis, 20 sacroiliac joints in 10 patients with osteoarthritis, and 30 sacroiliac joints of 15 asymptomatic volunteers were investigated on duplex and color Doppler sonography. We investigated whether a vessel was present around the posterior portions of sacroiliac joints with color Doppler sonography. When an artery was detected, the resistive index (RI) was measured using duplex Doppler sonography in all groups and also after treatment in the patients with active sacroiliitis. RESULTS: Vascularization around the posterior portions of sacroiliac joints was seen in 41 joints of the 21 patients with active sacroiliitis, nine joints of six patients with osteoarthritis, and 13 joints of eight volunteers. The mean RI values were 0.62 +/- 0.13, 0.91 +/- 0.09, and 0.97 +/- 0.03, respectively. In the patients with active sacroiliitis, the mean RI value was 0.91 +/- 0.07 after therapy. The RI values for the patients with active sacroiliitis were significantly different from those of the patients with osteoarthritis (p < .001) and of the volunteers (p < .001). In addition, the RI values were significantly different before and after treatment in the patients with active sacroiliitis (p < .001). CONCLUSION: Vascularization around the posterior portions of sacroiliac joints increased and RI values decreased in patients with active sacroiliitis. Color and duplex Doppler sonography were able to reveal these changes and can be used in the diagnosis of active sacroiliitis and follow-up after treatment. Thus, RI values may be a quantitative indicator for clinical symptoms in patients with active sacroiliitis.

Anatomic considerations of the principal nutrient foramen and artery on internal surface of the ilium.

Direct measurements of the nutrient foramen of thirty dried ilia using digital calipers and observations of the nutrient a. from ten cadaveric specimens were made in the present study. The nutrient foramen was situated 12.5 +/- 2.7 mm lateral to the anterosuperior sacroiliac joint line but perpendicular to this line and 23.5 +/- 5.8 mm above the pelvic brim parallel to the sacroiliac joint line. The nutrient a. originated from the iliolumbar a. as it coursed across the anterosuperior aspect of the sacroiliac joint. The present anatomic study indicates that the nutrient a. on the internal surface of the ilium is prone to injury as a result of traumatic disruption of the sacroiliac joint, sacral alar fractures and during the anterior approach to the sacroiliac joint.

División de la aorta abdominal terminal y comportamiento de la arteria sacra media / Division of the terminal abdominal aorta and the media sacra artery behavior

Con el objeto de analizar la forma de terminación más frecuente de la aorta abdominal y comprobar si ésta se trifurca o bifurca, al igual que el origen y distribución de la arteria sacra media, se diseca la región retroperitoneal media en su tercio distal y el espacio pre-sacro de 30 cadáveres adultos, de edades que fluctúan entre 40 y 70 años (27 de sexo masculino y 3, femenino). Los resultados que se entregan en tablas, gráficos y fotografías de las piezas anatómicas, permiten concluir que en el 83,3% de los casos, la altura de terminación de la aorta abdominal enfrenta al segmento de columna comprendido entre el disco intervertebral L4-L5 y el cuerpo vertebral L4. El ángulo subaórtico es de 56- en promedio. La arteria sacra media se origina como una rama dorsal de la aorta, en el 93,3% y la distancia a la terminación aórtica fluctúa entre 0,1 a 1 cm. en el 76,6% de los casos. Se concluye que la arteria sacra media, es una rama dorsal de la aorta abdominal y ésta termina bifurcándose en las arterias ilíacas comunes. Se recalca el interés de este hecho, para el cirujano que deba abordar la región

Scintigraphy in the diagnosis and management of septic sacro-iliitis.

Septic sacro-iliitis is a rare, life-threatening condition. The diagnosis is difficult, both clinically and radiographically, resulting in increased morbidity and delay in treatment. Skeletal scintigraphy is a sensitive method of establishing the diagnosis and monitoring progress. The blood pool image of the bone scan is the most informative part of the investigation.