Angiolipoma sacro. Reporte de un caso / Sacral angiolipoma. A case report

Fundamento: Los angiolipomas son tumores benignos que se presentan en adultos con una localización, preferentemente, en el espacio epidural posterior torácico. Objetivo: Presentar un caso que debutó con un traumatismo axial lumbosacro donde se evidenció una localización poco común de la lesión y sin relación con las estructuras del canal raquídeo. Presentación del caso: Hombre de 25 años que se cayó y debido a ello se le hizo un traumatismo directo en la región sacrococcígea con dolor y aumento de volumen regional, asociado a parestesias glúteas. Los estudios radiológicos evidenciaron una fractura del cóccix y la presencia de una lesión ubicada en las partes blandas, de aspecto redondeado, homogéneo, sólido, de poco más de 50 mm de diámetro. Se le realizó tratamiento quirúrgico que consistió en coccigectomía subperióstica y exéresis macroscópica de la masa. El estudio histológico concluyó el diagnóstico de un angiolipoma. Conclusiones: Los angiolipomas son tumores raros que tienen características radiológicas peculiares, requieren de alta sospecha clínico-imagenológica para indicar los estudios y el tratamiento. La exéresis total es recomendada para evitar la recurrencia y mejorar el pronóstico.

Background: Angiolipomas are benign tumors that appear in adults with special location in the posterior thoracic epidural position. Objective: To present a case that appeared with a lumbosacral axial trauma where a non-common lesion location was evidenced with no relation among the structures of the spinal canal. Case presentation: 25-year-old man who fell down, consequently suffered a painful direct trauma to the sacrococcygeal region and increased regional volume, associated with gluteal paresthesias. Radiological studies showed a fracture of the coccyx and presence of a lesion located in the soft tissues, with a rounded, homogeneous, solid aspect, a little more than 50 mm in diameter. Surgical treatment consisted of subperiosteal coccygectomy and macroscopic excision of the mass. Histological study concluded the diagnosis of an angiolipoma. Conclusions: Angiolipomas are rare tumors with peculiar radiological features, they require high clinical-imaging suspicion for studies and treatment. Total excision is recommended to avoid recurrence and improve prognosis.

Morel-Lavallée Lesion in the Sacrococcygeal Area with Associated Coccygeal Fracture / 대한신경손상학회지

A Morel-Lavallée lesion is a posttraumatic, closed internal degloving injury caused by shearing force abruptly separating the skin and superficial fascia from the deep fascia and creating a potential space. Blood, lymphatic fluid, and debris collect and fill the space. The most commonly affected sites are the thigh, knee, hip, and pelvic area, but the lesion can occur anywhere in the body. Among various treatments, surgical procedure is a good option if the lesion is chronic and a thick peripheral capsule has developed. We report an uncommon case of a chronic Morel-Lavallée lesion in the sacrococcygeal area, a rarely reported location, with an associated coccygeal fracture and dislocation.

Coccygeal Morphology on Multislice Computed Tomography in a Tertiary Hospital in India

STUDY DESIGN: A retrospective, cross-sectional study of 213 patients who presented for abdominal computed tomography (CT) scans to assess coccygeal morphology in the Indian population. PURPOSE: There have been relatively few studies of coccygeal morphology in the normal population and none in the Indian population. We aimed to estimate coccygeal morphometric parameters in the Indian population. OVERVIEW OF LITERATURE: Coccygeal morphology has been studied in European, American, Korean, and Egyptian populations, with few differences in morphology among populations. METHODS: A retrospective analysis of 213 abdominal CT scans (114 males and 99 females; age, 7–88 years; mean age, 47.3 years) was performed to evaluate the number of coccygeal segments, coccyx type, sacrococcygeal and intercoccygeal fusion and subluxation, coccygeal spicules, sacrococcygeal straight length, and sacrococcygeal and intercoccygeal curvature angles. Results were analyzed for differences in morphology with respect to sex and coccyx type. RESULTS: Types I and II coccyx were the most common. Most subjects had four coccygeal vertebrae; 93 subjects (43.66%) had partial or complete sacrococcygeal fusion. Intercoccygeal fusion was common, occurring in 193 subjects. Eighteen subjects had coccygeal spicules. The mean coccygeal straight length was 33.8 mm in males and 31.5 mm in females; the mean sacrococcygeal curvature angle was 116.6° in males and 111.6° in females; the mean intercoccygeal curvature angle was 140.94° in males and 145.10° in females. CONCLUSIONS: Type I was the most common coccyx type in our study, as in Egyptian and Western populations. The number of coccygeal vertebrae and prevalence of sacrococcygeal and intercoccygeal fusion in the Indian population were similar to those in the Western population. The mean coccygeal straight length and mean sacrococcygeal curvature angle were higher in males, whereas the intercoccygeal curvature angle was higher in females. Information on similarities and differences in coccygeal morphology between different ethnic populations could be useful in imaging and treating patients presenting with coccydynia.

Adult Stature Estimation by Multiple Parameters of Body Torso Segment / 法医学杂志

Objective T o prom ote the further research on body stature estim ation and the innovative ap-plications based on the distances betw een the anatom ical landm arks on body torso surface. Methods A specification for the collection of distances betw een the anatom ical landm arks on body torso surface w as established. T he data of 933 cases of adult population in Y angtze R iver D elta region w ere collected. M ultiple linear regression m ethod w as used to statistical analyse and establish the regression equation of stature estim ation. Results A regression equation about 5 variables including gender (x1), cervical verte-brae-coccyx line (x2), sterna-pubis line (x3), distance betw een acrom ion and iliospinale anterius (x4) and shoulder breadth (x5), and stature (y) w as established, y=105.406+5.414 x1+0.436 x2+0.286 x3+0.225 x4+0.193 x5. Conclusion T he m ethod is suitable for the rapid, sim ple and accurate estim ation of stature for the forensic experts.

Adult Stature Estimation by Multiple Parameters of Body Torso Segment / 法医学杂志

OBJECTIVES@#To promote the further research on body stature estimation and the innovative applications based on the distances between the anatomical landmarks on body torso surface.@*METHODS@#A specification for the collection of distances between the anatomical landmarks on body torso surface was established. The data of 933 cases of adult population in Yangtze River Delta region were collected. Multiple linear regression method was used to statistical analyse and establish the regression equation of stature estimation.@*RESULTS@#A regression equation about 5 variables including gender （x₁）, cervical vertebrae-coccyx line （x₂）, sterna-pubis line （x₃）, distance between acromion and iliospinale anterius （x₄） and shoulder breadth （x₅）, and stature （y） was established, y=105.406+5.414 x₁+0.436 x₂+0.286 x₃+0.225 x₄+ 0.193 x₅.@*CONCLUSIONS@#The method is suitable for the rapid, simple and accurate estimation of stature for the forensic experts.

Coccigectomía subperióstica total en la coccigodínia traumática crónica refractaria / Total subperiosteal coccygectomy for chronic traumatic refractory coccygodynia

Fundamento: la coccigodínia o dolor a nivel del cóccix es una condición poco frecuente con una incidencia no bien definida, que afecta cinco veces más a mujeres que hombres entre 30 y 50 años de edad y se asocia a la obesidad. La causa más común es el trauma como resultado de una caída sobre los glúteos, microtraumas repetitivos o el parto. Objetivo: presentar un caso de coccigectomía subperióstica total para el tratamiento de la coccigodínia traumática crónica refractaria. Caso clínico: paciente femenina de 51 años de edad, que acude a consulta con dolor en la región del cóccix, de cinco años de evolución debido a una caída sobre sus glúteos que se incrementaba a la defecación y el coito. Recibió numerosos tratamientos conservadores, sin mejoría clínica evidente por lo que dos años después se le practicó una coccigectomía parcial sin éxito. A la exploración física se constató dolor a la palpación, a nivel de la proyección de cóccix y tacto rectal doloroso con esfínter anal con buen tono y ampolla rectal vacía. Se realizó Rx de cóccix que no fue conclusivo para diagnóstico, por lo que se practicó una tomografía axial computarizada de sacro-cóccix con reconstrucciones en tercera dimensión que confirmaron la presencia íntegra del cóccix. Se realizó coccigectomía subperióstica total. Conclusiones: la coccigectomía subperióstica total es una técnica quirúrgica segura y factible en los enfermos con coccigodínia crónica refractaria, que puede mejorar los síntomas con un escaso porciento de complicaciones, siempre y cuando se llegue al diagnóstico adecuado de la causa que la provoca.

Background: coccygodynia or coccyx pain is an infrequent condition with an incidence that is not well defined. It affects women of 30 to 50 years of age five times more than men and it is associated with obesity. Trauma caused by falls, repetitive microtrauma or labor are the common causes. Objective: to present a case of total subperiosteal coccygectomy for the treatment for chronic traumatic refractory coccygodynia. Clinical case: a fifty-one year-old female patient, who attends a health center, with pain around the coccyx from five years of evolution due to a fall, increasing when defecating and having sexual intercourse. Numerous conservative treatments were given, without seeing evident clinical recovery. As a result, two years later, partial coccygectomy was performed. However, it did not have success. When examined physically, the patient felt pain in the coccyx projection and rectal examination with anal sphincter good tone and empty rectal ampulla. A coccyx X-ray that was not conclusive for diagnosis was carried out. Therefore, CT scans of sacrococcyx with 3D reconstructions which confirmed the complete presence of coccyx. Total subperiosteal coccygectomy was performed. Conclusions: total subperiosteal coccygectomy is a safe and feasible surgical technique in patients with chronic refractory coccygodynia, that can improve the symptoms with an scarce percentage of complications, as long as physicians give a right prognosis according to the cause that leads to it.

Analysis of Sacrococcygeal Morphology in Koreans Using Computed Tomography

BACKGROUND: The sacrococcygeal morphology of Arabs and Europeans has been studied using computed tomography (CT) or magnetic resonance imaging to determine the cause of coccydynia. Studies have suggested differences in sacrococcygeal morphology among ethnic groups. However, there are no data on the sacrococcygeal anatomy of Koreans. METHODS: We conducted a retrospective analysis of 606 pelvic CT scans that were taken at Cheju Halla General Hospital between 2008 and 2014. Fractures of the sacrum or coccyx were excluded. Differences in the sacrococcygeal morphology among age groups stratified by decade of life and between genders were analyzed using sagittal plane pelvic CT scans. The morphological parameters studied were the sacral and coccygeal curved indexes, sacrococcygeal angle, intercoccygeal angle, coccygeal type, coccygeal segmental number, and sacrococcygeal fusion. RESULTS: The average sacral and coccygeal curved indexes were 6.15 and 7.41, respectively. The average sacrococcygeal and intercoccygeal angles were 110° and 49°, respectively. Type II coccyx was most common, and the rate of sacrococcygeal fusion was 34%. There was a moderate positive correlation between age and the sacral curved index (r = 0.493, p = 0.000) and a weak negative correlation between age and the coccyx curved index (r = −0.257, p = 0.000). There was a weak negative correlation between age and the intercoccygeal angle (r = −0.187, p = 0.000). The average intercoccygeal angle in males and females was 53.9° and 44.7°, respectively. CONCLUSIONS: The sacrum tended to be more curved and the coccyx straighter with age. The coccyx was straighter in females than males. Knowledge of the sacrococcygeal anatomy of Koreans will promote better understanding of anatomical differences among ethnicities and future studies on coccydynia.

Classification and analysis of fifth pair of sacral foramina in indian dry sacra / Clasificación y análisis del quinto par de forámenes en huesos sacros secos de indios

A sacrum with five pairs of foramina is an anatomical variant resulting from sacralisation of lumbar vertebra at cranial end or sacralisation of coccyx vertebra at caudal end. An unusual gross variation nurtures interest of anatomists and causes concern for clinicians when it mimics pathology. A sacrum with fifth anomalous pair of sacral foramina has been observed which prompted the author to examine the available sacra in the osteology lab of Department of Anatomy KG Medical University Lucknow, UP, India. Of the total sixty six observed sacra, those with five pairs of sacral foramina due to sacralisation of lumbar vertebra were found in eleven cases (16.6%) while those due to sacralisation of coccygeal vertebra were observed in nine cases (13.6%). These sacralisations were classified in five categories to systematise the anatomical study, causes and clinical complications. Sacralisation of lumbar vertebra may compress the fifth sacral nerve causing sciatica and back pain. It may also cause herniation of disc above sacralisation. Sacralisation of coccygeal vertebra may influence the caudal block anaesthesia in surgical procedures and also results in prolonged second stage of labor and perineal tears.

Un sacro con cinco pares de forámenes es una variante anatómica que resulta de la sacralización de la vértebra lumbar al extremo craneal o sacralización de la vértebra coxis al extremo caudal. Esta variación inusual es de interés para los anatomistas como también motivo de preocupación para los médicos al asemejar una patología. Un sacro con un quinto par anómalo de forámenes fue observado, por lo que se examinaron otros sacros del laboratorio de osteología del Departamento de Anatomía Médica de la Universidad de Lucknow, India. De un total de 66 sacros estudiados, en 11 casos (16,6%) se observaron cinco pares de forámenes sacros, debido a la sacralización de la vértebra lumbar; mientras que en 9 casos (13,6%), se observó la sacralización de la vértebra caudal. Estos fueron clasificados en cinco categorías para sistematizar el estudio anatómico, sus causas y complicaciones clínicas. La sacralización de la vértebra lumbar puede comprimir el quinto nervio, causando ciática sacra y dolor de espalda. También puede causar una hernia discal superior a la sacralización. La sacralización de la vértebra caudal, puede influir en la anestesia de bloqueo caudal en procedimientos quirúrgicos y también dar lugar a una prolongada etapa del trabajo de parto y desgarros perineales.

An Experimental Study on Bovine Nucleus Pulposus Cells Labelled with PKH26 in Vitro / 天津医药

Objective To investigate the application of PKH26 fluorescent labeling on nucleus pulposus cells isolat-ed from bovine coccyx disc, and to provide nucleus pulposus tissue engineering with traceable nucleus pulposus cells by PKH26 fluorescence labelling. Methods Nucleus pulposus primary cells were isolated from the nucleus pulposus tissue de-tached from bovine coccyx disc by enzymatic digestion, and observed under the inverted microscope. Safranin O, toluidine blue and type Ⅱ collagen immunocytochemistry methods used to stain for passage one generation cells. Nucleus pulposus cells were labeled with PKH26 fluorescence in accordance with the instructions. The cell activity, fluorescence intensity at d0, d14 and d28 of culture, characteristics of proliferation and the expression of gene in labeled cells were assessed. Re-sults Isolated nucleus pulposus cells amounted to (1.56 ± 0.35) × 106/g. Under the inverted microscope, primary cells ad-hered at the 4 th day of culture, grew in groups, and covered the bottom of culture flask at the 13 th day. Both primary cells and the P1 generation cells were chondrocyte-like morphology. The staining of safranin O, toluidine blue and typeⅡcolla-gen immunocytochemistry for P1 generation of nucleus pulposus cells showed positive results. The cell activity before and af-ter PKH26 labeling showed more than 95%, and the fluorescence intensity at d0, d14 and d28 performed a decreasing trend, but still showed detect strong fluorescence at d28. There were no significant differences in proliferation and the expression of gene (collagen typeⅠandⅡ, aggrecan) before and after cell labeling (P>0.05). Conclusion As the seed cells of tissue en-gineering, nucleus pulposus cells isolated from bovine coccyx can reach a satisfactory number and maintain cartilage-like phenotype, and no changes shown in the biological characteristics after labeling. PKH26 labeled nucleus pulposus cells are suitable for the traceable cells in vivo study.

Coccygectomy as a Surgical Option in the Treatment of Chronic Traumatic Coccygodynia: A Single-Center Experience and Literature Review

STUDY DESIGN: Retrospective cohort study. PURPOSE: Trauma is the most common cause for chronic coccygodynia. The present study aims at presenting our results after complete removal of the coccyx for refractory traumatic coccygodynia in terms of pain level, complication rates, and patients' overall satisfaction. OVERVIEW OF LITERATURE: There is limited extant literature describing the success rate and complications in refractory isolated traumatic coccygodynia. METHODS: From January 2011 to January 2012, 10 consecutive patients with posttraumatic coccygodynia (six males and four females; mean age, 42 years) were enrolled in our study. Conservative treatment of the condition had failed in all patients. The same surgeon performed a complete coccygectomy on all patients. Postoperative outcomes included measurements of pain relief and degree of patient satisfaction with the procedure's results. RESULTS: In our selected cohort, all patients indicated complete pain relief or significant pain improvement in follow up-care and would recommend this procedure. One patient developed a subcutaneous hematoma that required surgical intervention. CONCLUSIONS: Our results suggest that complete removal of the coccyx relieves pain in patients with refractory chronic traumatic coccygodyniaand is therefore a reasonable treatment option after conservative treatment failure.

Isolated Coccygeal Tuberculosis

Isolated tuberculosis of the coccyx is extremely rare. A 35-year-old man presented with a 3-month history of coccygeal and gluteal pain. Computed tomography and magnetic resonance imaging revealed osseous destruction and a large enhancing mass involving the coccyx with anterior and posterior extension. Pathologic examination of the surgical specimen revealed necrosis, chronic granulomatous inflammation, and multinucleated giant cells consistent with tuberculosis. This case highlights the importance of considering tuberculosis as a diagnosis even though unusual sites are involved.

Anatomical and Biomechanical Study of Sacral Pedicle and Lateral Mass / 医用生物力学

Objective To study the anatomical and biomechanical features of sacral pedicle and lateral mass to provide evidence for clinical sacral pedicle and lateral mass screw fixation technology. Method 60 adult patient's spiral CT images of sacrum and coccyx were selected randomly. The sacral pedicle and lateral mass screw entry point was determined, and the crew trajectory were measured using the three dimensional reconstruction. Meanwhile, the gross anatomy was done for 15 adult cadavers to determine the sacral pedicle and lateral mass screw entry point. The length, width and angle of sacral pedicle and lateral mass screw trajectory was measured. 8 of 15 cadaver specimens were selected to test for the maximal extraction force for sacral pedicle and lateral mass screws. ResultsThe diameter and length of S1～S5 sacral pedicle and lateral mass screw trajectory are significantly regular, with inclination angle is about 20°. The S1 pedicle screw entry point is located at intersection point of basal lateral part of articular process and median line of transverse process, no significant difference is found between the maximal extraction force of pedicle and lateral mass screws (P>0.05）. The entry points of S2～5 pedicle screws are located at the intersection point of the line connecting adjacent posterior sacral foramina and median line of transverse process. The lateral mass screw entry point of S2～5 is on the median side of intersection point between median line of transverse process and lateral sacral crest. The maximal extraction force of pedicle screws are significantly different from the lateral mass screws（P<0.05）. Conclusions Both the sacral pedicle and the lateral mass screw fixation technology can offer effective fixation and reconstruction for the fracture of sacrum and coccyx, but the pedicle screw fixation may be more convenient, safe and reliable than the lateral mass screw fixation technology.

Two Cases of Coccygeal Polypoid Eccrine Nevi Presenting as Skin Tags

An eccrine nevus is a rare hamartoma characterized by an increase in the number or size of eccrine glands. Eccrine nevi usually present as localized hyperhidrosis and are not associated with overlying skin abnormalities. However, among the cases that have been reported in the literature, some unique presentations of eccrine nevi have been demonstrated, including a pigmented patch, a depressed nodule, linear papules, and a sacral skin tag. Herein, we report two unusual cases of coccygeal polypoid eccrine nevi and review the literature.

Coccigodínias: diagnóstico por imagem / Coccygodynia: diagnostic imaging

Coccigodínia é uma síndrome dolorosa de difícil abordagem diagnóstica e terapêutica, ainda mal compreendida por clínicos, ortopedistas e radiologistas. No intuito de entender e diferenciar as anormalidades clínico-radiológicas encontradas nas coccigodínias, revisamos a anatomia normal do sacro-cóccix e das demais estruturas pélvicas, suas variações e alterações anatômicas, além doselementos biomecânicos e fisiopatológicos implicados na etiologia da dor. O estudo radiológico funcional do cóccix consiste na obtenção de incidências de perfil nas posições ortostática e sentada, que permite a determinação da mobilidade coccígea. Este método pode demonstrar lesãocausal em 70% dos casos de coccigodínia. A classificação radiológica segundo as alterações da dinâmica do cóccix pode orientar tratamentos e comparar respostas terapêuticas por subgrupos.

Coccygodynia is a painful syndrome still misunderstood by physicians. To understand the radiological abnormalities that may accompanythis syndrome we have revised sacro-coccygeal normal anatomy and its variants and biomechanical elements that may produce pain. Functional radiologic studies of the coccyx consistin lateral projection in upright and sitted positions. Such projections provide clues for the evaluation of coccygeal mobility and may disclose the causal lesion producing coccygodynia in about 70%of the patients. Radiologic classification of the dynamic dysfunctions of coccygeal mobility may orient treatments and compare outcomes in subgroups.

Nuchal-type Fibroma of the Coccyx

Nuchal-type fibroma is a recently described, rare, tumor-like process of fibrous tissue occurring chiefly in the dorsocervical area. Nuchal-type fibromas in extranuchal locations are morphologically indistinguishable from lesions involving the nuchal region. Histopathologic findings of nuchal-type fibroma are poorly demarcated, dense collagen bundles with sparsely scattered fibroblasts, some interspersed adipose tissue, and entrapped nerve fibers. We report a patient with a mass on the coccyx area, and these were histopathologically consistent with nuchal-type fibroma. This tumor was surgically excised, and no recurrence had been noted during the two year follow-up period.

Useful Lateral Views of Sacrococcygeal Region in Skeletal Scintigraphy / 대한핵의학회잡지

A tail-on-detector (TOD) view has been used to see the symphysis pubis or sacrococcyx in skeletal scintigraphy, but it is inconvenient to acquire because a patient must sit or lean on a detector. The TOD views are still frequently performed in training hospitals in Korea, although it is becoming almost impossible to sit on a camera in this age of dual-headed cameras. The authors show cases with lateral views obtained in supine position that were acquired for the same reason; they are easier and more useful than the TOD views.

Sonographic Findings of Coccygeal Abscess in the Neonates

PURPOSE: The purpose of this study was to report the sonographic findings of neonatal coccygeal abscess,previously not described. MATERIALS AND METHODS: Eighteen neonates (5-18 days old) presented with swelling in thecoccygeal area and by either open drainage (n=13) or follow-up after antibiotic therapy (n=5), this was diagnosedas coccygeal abscess. We retrospectively reviewed the size, shape, location, echo pattern and marginalcharacteristics of the abscesses, as seen on sonography, as well as their intradural content and relationship withthe spine. Additional MR images (n=5) were separately reviewed. RESULTS: Mean longest diameter of the abscesseswas 1.5cm (range, 0.8-2.3); they were oval or round and located in the subcutaneous fat layer. Echogenicitycompared with surrounding fat varied: in nine patients it was isoechoic, and in nine, hypoechoic. Internalechogenicity was homogenous in 14 patients and heterogeneous in four, and in seven cases, the margin of theabscess was well demarcated. Intradural structure and bony spines were normal, and the possibility of spinaldysraphism, could thus be excluded. All cases except one were correctly diagnosed by sonography and clinicalfindings; on sonography, the echogenicity of one lesion was exactly the same as that of lipoma, and it was thusmisdiagnosed. In cases where sonography revealed an isoechoic mass, the use of MR excluded the possibility oflipoma. Three of five cases showed marginal or diffuse enhancement on contrast enhanced MR images. CONCLUSION: Coccygeal absesses were confined to the subcutaneous fat layer and were either iso- or hypoechoic compared. withsurrounding fat. In neonates, abscess formation in the coccygeal area is possible, and coccygeal abscess shouldtherefore be included in the differentiation of coccygeal masses.

THE ARTERIAL SUPPLY OF THE HUMAN SACRUM AND COCCYX——INTRA-OSSEOUS PART / 解剖学报

The arterial supply of the human sacrum and coccyx was studied in 68 fresh cadavers of different ages by dissection, clearing, casting and radiography.The nutrient arteries of the sacral vertebrae penetrate the body from the dorsal, ventral and lateral surfaces of the body. The central branches are the main nutrient arteries of the body. Their numbers are constant and do not increase with the advancement of age. The peripheral branches are variable and supply only the outer collar of the body. According to the distribution of nutrient artery within the body of the sacrum, they can be classified into three types 1. predominant ventral nutrient artery pattern, 2. predominant dorsal nutrient artery pattern and 3. balanced nutrient artery pattern. It is found that in S_4 and S_5, type 1 occurs more frequently while type 2 occurs usually in S_1 to S_3. Type 1 is relatively common in adults but type 2 is prevailing in fetuses. There is few balanced pattern in different age groups. Both ventral and dorsal nutrient arteries are distributed in the central zone of the body and the lateral nutrient arteries supply that portion near the intervertebral foramen in the adults. The nutrient arteries within body anastomose with each other to form a dense arterial network.The nutrient arteries of the lateral part of the sacrum enter the bone through its ventral, dorsal and medial aspects. Among the dorsal nutrient arteries, there is a main artery that supplies the lateral mass.The arterial supply to the coccyx is scarce. It enters the coccyx mainly through the ventral surface.

THE ARTERIAL SUPPLY OF THE HUMAN SACRUM AND COCCYX——EXTRA- OSSEOUS PART / 解剖学报

The arterial supply of the human sacrum and coccyx was studied on 56 fresh. cadavers of different ages by dissection, clearing, casting and radiography.All sacrums receive their blood supply from the lateral sacral arteries, the median sacral artery, the iliolumbar arteries and the fifth lumbar arteries. The median sacral artery, the lateral sacral arteries and their branches anastomose with each other and form the lattice anastomosis on the ventral surface of the sacrum.The anterior spinal canal branch bifurcates into an ascending and a descending branches. The former passes upwards to join the descending branch from the anterior spinal canal branch above it, they also anastomose with their contralateral counterparts, thus forming a rhombic system notable for its regularity.The posterior spinal canal branch also divides into an ascending and a descending branches and they join each other to dispose in a ladder anastomosis on the ventral surface of the laminae.The dorsal branch gives off three main sets of branches: the lateral, the medial and the muscular. The medial and the lateral branches both subdivide into an ascending and a descending branches and they anastomose with each other on the dorsal aspect of the sacrum.On the ventral surface, the coccyx obtains arterial supply from the median sacral artery and the lateral sacral arteries, while its dorsal surface mainly receives blood supply of the lateral sacral artery. Anastomosis has been found scarce on the ventral and dorsal surfaces of the coccyx.