Glomerular Endothelial Cell Receptor ADGRF5 and the Integrity of the Glomerular Filtration Barrier.

BACKGROUND: Glomerular endothelial cells are recognized to be important for maintaining the glomerular filtration barrier. ADGRF5, an adhesion G protein-coupled receptor, has been suggested to be involved in endothelial cell function. However, the role of ADGRF5 in the glomerular filtration barrier integrity remains elusive. METHODS: Cellular expression of ADGRF5 in mouse glomerulus was determined by histological analyses. The impact of ADGRF5 deletion on the glomerular morphology, kidney function, and glomerular endothelial gene/protein expression was then analyzed using ADGRF5 knockout (Adgrf5-/-) mice and human primary glomerular endothelial cells. RESULTS: ADGRF5 was specifically expressed in the capillary endothelial cells within the glomerulus. Adgrf5-/- mice developed albuminuria and impaired kidney function with morphological defects in the glomeruli, namely glomerular hypertrophy, glomerular basement membrane splitting and thickening, diaphragmed fenestration and detachment of the glomerular endothelial cells, and mesangial interposition. These defects were accompanied by the altered expression of genes responsible for glomerular basement membrane organization (type IV collagens and laminins) and Krüppel-like factor 2 (Klf2) in glomerular endothelial cells. Moreover, ADGRF5 knockdown decreased COL4A3 and COL4A4 expression and increased KLF2 expression in human primary glomerular endothelial cells. CONCLUSIONS: The loss of ADGRF5 resulted in altered gene expression in glomerular endothelial cells, and perturbed the structure and permselectivity of the glomerular filtration barrier.

The three layered structure of orbicularis oris and buccinator complex with partial connection at the modiolus and partial direct continuation.

PURPOSE: This study aimed to clarify the structural arrangement of the orbicularis oris (OOr), the buccinator, and the other perioral muscles around the modiolus. METHODS: The perioral muscles in seventeen cadavers fixed with formalin were dissected in situ and/or in isolated muscle specimens, and their layers were reconstructed schematically upon pantomographic view of the skeleton to evaluate their actions. RESULTS: The buccinator was composed of three parts including upper and lower oblique parts in its superficial layer and a middle transverse part in its deep layer. The superior and inferior OOr were composed of an inner marginal part (IM) and an outer labial part (OL) in each. The perioral muscles as a whole were arranged in three layers. The first layer consisted of the depressor anguli oris and the OL of superior OOr connected at the modiolus in a vertical direction. The second layer consisted of the upper and inner oblique part of buccinator and a part of the OL of inferior OOr connected at the modiolus in a horizontal direction. The third layer contained the middle transverse part of buccinator continuous with the IM of both OOr and a part of the OL of inferior OOr without connection to the modiolus. CONCLUSIONS: The different arrangement of the three layers of perioral muscles around the modiolus could serve as a good basis to predict the actions of the individual perioral muscles on the movement of lips in open/close of the oral fissure and widening/narrowing of the lip width.

Unique morphological architecture of the hamstring muscles and its functional relevance revealed by analysis of isolated muscle specimens and quantification of structural parameters.

The structural and functional differences of individual hamstrings have not been sufficiently evaluated. This study aimed to clarify the morphological architecture of the hamstrings including the superficial tendons in detail using isolated muscle specimens, together with quantification of structural parameters of the muscle. Sixteen lower limbs of human cadavers were used in this study. The semimembranosus (SM), semitendinosus (ST), biceps femoris long head (BFlh), and biceps femoris short head (BFsh) were dissected from cadavers to prepare isolated muscle specimens. Structural parameters, including muscle volume, muscle length, fiber length, sarcomere length, pennation angle, and physiological cross-sectional area (PCSA) were measured. In addition, the proximal and distal attachment areas of the muscle fibers were measured, and the proximal/distal area ratio was calculated. The SM, ST, and BFlh were spindle-shaped with the superficial origin and insertion tendons on the muscle surface, and the BFsh was quadrate with direct attachment to the skeleton and BFlh tendon. The muscle architecture was pennate in the four muscles. The four hamstrings possessed either of two types of structural parameters, one with shorter fiber length and larger PCSA, as in the SM and BFlh, and the other with longer fiber length and smaller PCSA, as in the ST and BFsh. Sarcomere length was unique in each of the four hamstrings, and thus the fiber length was suitably normalized using the average sarcomere length for each, instead of uniform length of 2.7 µm. The proximal/distal area ratio was even in the SM, large in the ST, and small in the BFsh and BFlh. This study clarified that the superficial origin and insertion tendons are critical determinants of the unique internal structure and structural parameters representing the functional properties of the hamstring muscles.

Evolution of microneurosurgical anatomy with special reference to the history of anatomy, surgical anatomy, and microsurgery: historical overview.

This article reviews the evolution of microneurosurgical anatomy (MNA) with special reference to the development of anatomy, surgical anatomy, and microsurgery. Anatomy can be said to have started in the ancient Greek era with the work of Hippocrates, Galen, and others as part of the pursuit of natural science. In the sixteenth century, Vesalius made a great contribution in reviving Galenian knowledge while adding new knowledge of human anatomy. Also in the sixteenth century, Ambroise Paré can be said to have started modern surgery. As surgery developed, more detailed anatomical knowledge became necessary for treating complicated diseases. Many noted surgeons at the time were also anatomists eager to spread anatomical knowledge in order to enhance surgical practice. Thus, surgery and anatomy developed together, with advances in each benefiting the other. The concept of surgical anatomy evolved in the eighteenth century and became especially popular in the nineteenth century. In the twentieth century, microsurgery was introduced in various surgical fields, starting with Carl O. Nylen in otology. It flourished and became popularized in the second half of the century, especially in the field of neurosurgery, following Jacobson and Suarez's success in microvascular anastomosis in animals and subsequent clinical application as developed by M.G. Yasargil and others. Knowledge of surgical anatomy as seen under the operating microscope became important for surgeons to perform microneurosurgical procedures accurately and safely, which led to the fuller development of MNA as conducted by many neurosurgeons, among whom A.L. Rhoton, Jr. might be mentioned as representative.

Anatomical study of the soleus: Application to improved imaging diagnoses.

INTRODUCTION: Strains of the soleus are widely found both in amateur and professional athletes. For their accurate regional diagnoses, understanding the anatomy of the spatial relationship between muscular fibers and tendinous structures is important because their interfaces are susceptible sites to muscle strains. Therefore, this study evaluated the precise architecture of the soleus. MATERIALS AND METHODS: We evaluated the precise anatomical architecture of the soleus in 87 formaldehyde-fixed soleus muscles. To calculate mean relative physiological cross-sectional area of each muscular fiber compartment, we measured the fiber length, volume, and pennation angle in isolated compartments. RESULTS: The posterior soleus surface was covered by a broad aponeurotic posterior insertion tendon (PIT), which continued inferiorly to the insertion tendon. The anterior surface had three aponeurotic origin tendons, lateral origin tendon (LOT), medial origin tendon (MOT), and tendinous arch, which were arranged along the soleus margins. The anterior bipennate muscle portion (ABP), surrounded by the three origin structures, terminated as the sagittal insertion tendon (SIT), which continued inferiorly to PIT. The posterior main muscle portion behind LOT and MOT was separated into lateral and medial portions by the SIT. The soleus thus possessed a broad musculotendinous junction. Furthermore, ABP exhibited wide structural diversity in shape and size: in extreme cases, it was duplicated or absent. CONCLUSION: Systematic anatomical descriptions of the soleus will be useful for accurate regional diagnosis of its strains with magnetic resonance imaging and ultrasonography.

Nephrocytes are part of the spectrum of filtration epithelial diversity.

The excretory system produces urine by ultrafiltration via a filtration epithelium. Podocytes are widely found as filtration epithelial cells in eucoelomates. In some animal taxa, including insects and crustaceans, nephrocytes serve to separate toxic substances from the body fluid, in addition to podocytes. Drosophila nephrocytes have been recently utilized as a model system to study podocyte function and disease. However, functionality and cellular architecture are strikingly different between Drosophila nephrocytes and eucoelomate podocytes, and the phylogenetic relationship between these cells remains enigmatic. In this study, using focused-ion beam-scanning electron microscopy (FIB-SEM) tomography, we revealed three-dimensional architecture of decapod nephrocytes with unprecedented accuracy-they filled an enormous gap, which can be called "missing link," in the evolutionary diversity of podocytes and nephrocytes. Thus, we concluded that nephrocytes are part of the spectrum of filtration epithelial diversity in animal phylogeny.

Three-dimensional imaging of podocyte ultrastructure using FE-SEM and FIB-SEM tomography.

Podocytes are specialized epithelial cells used for glomerular filtration in the kidney. They can be divided into the cell body, primary process and foot process. Here, we describe two useful methods for the three-dimensional(3D) visualization of these subcellular compartments in rodent podocytes. The first method, field-emission scanning electron microscopy (FE-SEM) with conductive staining, is used to visualize the luminal surface of numerous podocytes simultaneously. The second method, focused-ion beam SEM (FIB-SEM) tomography, allows the user to obtain serial images from different depths of field, or Z-stacks, of the glomerulus. This allows for the 3D reconstruction of podocyte ultrastructure, which can be viewed from all angles, from a single image set. This is not possible with conventional FE-SEM. The different advantages and disadvantages of FE-SEM and FIB-SEM tomography compensate for the weaknesses of the other. The combination renders a powerful approach for the 3D analysis of podocyte ultrastructure. As a result, we were able to identify a new subcellular compartment of podocytes, "ridge-like prominences" (RLPs).

Morphological Processes of Foot Process Effacement in Puromycin Aminonucleoside Nephrosis Revealed by FIB/SEM Tomography.

BACKGROUND: Foot process effacement is one of the pathologic indicators of podocyte injury. However, the morphologic changes associated with it remain unclear. METHODS: To clarify the developmental process, we analyzed puromycin nephrotic podocytes reconstructed from serial focused-ion beam/scanning electron microscopy (FIB/SEM) images. RESULTS: Intact podocytes consisted of four subcellular compartments: cell body, primary process, ridge-like prominence (RLP), and foot process. The RLP, a longitudinal protrusion from the basal surface of the cell body and primary process, served as an adhesive apparatus for the cell body and primary process to attach to the glomerular basement membrane. Foot processes protruded from both sides of the RLP. In puromycin nephrotic podocytes, foot process effacement occurred in two ways: by type-1 retraction, where the foot processes retracted while maintaining their rounded tips; or type-2 retraction, where they narrowed across their entire lengths, tapering toward the tips. Puromycin nephrotic podocytes also exhibited several alterations associated with foot process effacement, such as deformation of the cell body, retraction of RLPs, and cytoplasmic fragmentation. Finally, podocytes were reorganized into a broad, flattened shape. CONCLUSIONS: The three-dimensional reconstruction of podocytes by serial FIB/SEM images revealed the morphologic changes involved in foot process effacement in greater detail than previously described.

Anatomic Analysis of the Attachment of the Posteroinferior Labrum and Capsule to the Glenoid: A Cadaveric Study.

PURPOSE: To measure the height of the posteroinferior glenohumeral ligament (PIGHL) attachment to the labrum and the depth of the posteroinferior labrum to the glenoid, macroscopically, and to investigate the morphology of the attachment of the posteroinferior labrum to the glenoid, histologically. METHODS: Fifty cadaveric shoulders without exposed subchondral bone on the glenoid and detached posterior labrum were used. We examined the frequency of the heights of the PIGHL attachments to the labrum and the length of the labral attachment on the glenoid rim at the 7, 8, 9, and 10 o'clock positions, macroscopically. According to morphology of the histological labral attachments, it was divided into 3 groups. Labra attached on the articular surface and the glenoid neck were defined as the SN type, while labra attached only to the glenoid neck constituted labra attached to the bone and side of the articular cartilage (Nc type) and labra attached only to bone (Nb type). RESULTS: The PIGHL attached from 7 o'clock to 9 o'clock in 48 shoulders (96%). The mean labral attachment at the 7 o'clock position was 6.3 ± 1.0 mm (range, 4.6-9.4 mm), which was significantly longer than at the other positions (P < .05). Histologically, the frequency of SN type attachment was 49 (98%) shoulders at the 7 o'clock position. CONCLUSIONS: The PIGHL attached between 7 and 9 o'clock in 96% of the shoulders. In 98% of the shoulders, the labrum did not attach to the articular surface, but attached to both the articular cartilage and the bone of the glenoid neck at 7 o'clock. CLINICAL RELEVANCE: The posteroinferior labrum should be repaired widely at the 7 o'clock position and not on the articular surface because the labrum attached anatomically to the glenoid neck.

Anatomic characterization of the femoral nutrient artery: Application to fracture and surgery of the femur.

The localization of nutrient foramina and direction of nutrient canals have been studied. However, information about the origin and extraosseous course of nutrient arteries is lacking in some types of long tubular and irregular bones. Thus, we aimed to reexamine the origin and course of the femoral nutrient artery (FNA) through cadaveric dissection to clarify its anatomic characteristics. Sixty thighs were collected from 57 cadavers. To fix the cadavers and visualize the small arterial branches, 10% formalin was injected from the femoral artery, followed by an injection of acrylic ink. The arterial tree in the posterior part of the thigh was recorded by line drawings. The femur received single or double FNAs via the femoral nutrient foramina, which were on and along the linea aspera. In cases with single FNA (41 of the 60 thighs), it typically arose from the four parts of the profunda femoris system: profunda femoris artery between the origins of the third and fourth perforating arteries; second perforating artery; third perforating artery; and terminal branch. In cases with double FNAs (remaining 19 thighs), the superior FNA typically arose from the second perforating artery, and the inferior FNA arose from the terminal branch of the profunda femoris artery and popliteal system. FNAs are described as branches of the perforating arteries in Terminologia Anatomica and anatomy textbooks. However, we found that FNAs also frequently arose from the profunda femoris artery and popliteal system, in addition to the perforating arteries. Clin. Anat. 33:479-487, 2020. © 2019 Wiley Periodicals, Inc.

Morphological process of podocyte development revealed by block-face scanning electron microscopy.

Podocytes present a unique 3D architecture specialized for glomerular filtration. However, several 3D morphological aspects on podocyte development remain partially understood because they are difficult to reveal using conventional scanning electron microscopy (SEM). Here, we adopted serial block-face SEM imaging, a powerful tool for analyzing the 3D cellular ultrastructure, to precisely reveal the morphological process of podocyte development, such as the formation of foot processes. Development of foot processes gives rise to three morphological states: the primitive, immature and mature foot processes. Immature podocytes were columnar in shape and connected to each other by the junctional complex, which migrated toward the basal side of the cell. When the junctional complex was close to the basement membrane, immature podocytes started to interdigitate with primitive foot processes under the level of junctional complex. As primitive foot processes lengthened, the junctional complex moved between primitive foot processes to form immature foot processes. Finally, the junctional complex was gradually replaced by the slit diaphragm, resulting in the maturation of immature foot processes into mature foot processes. In conclusion, the developmental process of podocytes is now clearly visualized by block-face SEM imaging.

Three-dimensional architecture of pericardial nephrocytes in Drosophila melanogaster revealed by FIB/SEM tomography.

Nephrocytes are similar in structure to podocytes and play a role in the isolation of toxic substances from hemolymph in insects. Drosophila melanogaster nephrocytes have recently been used to study podocyte function and disease. However, the three-dimensional ultrastructure of nephrocytes is not clearly understood because their surrounding basement membrane makes it difficult to observe using conventional scanning electron microscopy. We reconstructed the three-dimensional ultrastructure of Drosophila pericardial nephrocytes using serial focused-ion beam/scanning electron microscopy (FIB/SEM) images. The basal surfaces were occupied by foot processes and slit-like spaces between them. The slit-like spaces corresponded to the podocyte filtration slits and were formed by longitudinal infolding/invagination of the basal plasma membrane. The basal surface between the slit-like spaces became the foot processes, which ran almost linearly, and had a "washboard-like" appearance. Both ends of the foot processes were usually anastomosed to neighboring foot processes and thus free ends were rarely observed. We demonstrated that FIB/SEM is a powerful tool to better understand the three-dimensional architecture of nephrocytes.

A new technique of surgical planning for anterior cruciate ligament reconstruction: Feasibility Assessment of Shear Wave Elastography to Tendon of Semitendinosus Muscle.

There is currently no method to quantify the quality of the harvested graft before anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to explore a method for measuring stiffness of the normal tendon of the semitendinosus muscle using shear wave elastography (SWE). Our investigation comprised two steps. First, we determined orientation of the semitendinosus tendon fibers in 20 lower legs of embalmed cadavers. Second, we investigated the feasibility of quantifying stiffness of the normal semitendinosus tendon by SWE in 24 subjects (48 legs: 24 male and 24 female subjects) in vivo. Measured values were compared between male and female subjects. The point at the intersection of the semitendinosus tendon with the axial section through the center of the patella mostly was the middle of the semitendinosus tendon in the cadavers. The SWE modulus in all of the subjects could be measured on this point in vivo. The SWE modulus of males and females were 474.0 ± 71.9 kPa and 396.9 ± 104.5 kPa, respectively. The SWE modulus of males was significantly larger than that of females (P < 0.01). This study demonstrates that stiffness of the tendon of the semitendinosus muscle can be measured by SWE. It also shows that tendon of the semitendinosus muscle in males is stiffer than in females. Clin. Anat. 31:404-408, 2018. © 2017 Wiley Periodicals, Inc.

Cathepsin D in Podocytes Is Important in the Pathogenesis of Proteinuria and CKD.

Studies have revealed many analogies between podocytes and neurons, and these analogies may be key to elucidating the pathogenesis of podocyte injury. Cathepsin D (CD) is a representative aspartic proteinase in lysosomes. Central nervous system neurons in CD-deficient mice exhibit a form of lysosomal storage disease with a phenotype resembling neuronal ceroid lipofuscinoses. In the kidney, the role of CD in podocytes has not been fully explored. Herein, we generated podocyte-specific CD-knockout mice that developed proteinuria at 5 months of age and ESRD by 20-22 months of age. Immunohistochemical analysis of these mice showed apoptotic podocyte death followed by proteinuria and glomerulosclerosis with aging. Using electron microscopy, we identified, in podocytes, granular osmiophilic deposits (GRODs), autophagosome/autolysosome-like bodies, and fingerprint profiles, typical hallmarks of CD-deficient neurons. CD deficiency in podocytes also led to the cessation of autolysosomal degradation and accumulation of proteins indicative of autophagy impairment and the mitochondrial ATP synthase subunit c accumulation in the GRODs, again similar to changes reported in CD-deficient neurons. Furthermore, both podocin and nephrin, two essential components of the slit diaphragm, translocated to Rab7- and lysosome-associated membrane glycoprotein 1-positive amphisomes/autolysosomes that accumulated in podocyte cell bodies in podocyte-specific CD-knockout mice. We hypothesize that defective lysosomal activity resulting in foot process effacement caused this accumulation of podocin and nephrin. Overall, our results suggest that loss of CD in podocytes causes autophagy impairment, triggering the accumulation of toxic subunit c-positive lipofuscins as well as slit diaphragm proteins followed by apoptotic cell death.

Structural diversity of the vastus intermedius origin revealed by analysis of isolated muscle specimens.

The quadriceps femoris (QF), a major extensor of the knee joint, plays an important role in human movement. However, descriptions of the three vastus muscles of the QF in anatomy textbooks remain confusing. We analyzed 33 QFs by a novel approach, using isolated muscle specimens to clarify the structures of the vastus lateralis (VL), vastus medialis (VM), and vastus intermedius (VI) origins. The origins of the VL and VM were quite constant in shape and location, but the VI was much more structurally diverse. In typical cases (23 of 33), the origin of the VI attached muscularly to the anterior and lateral surface of the femoral shaft. It adjoined the origin of the VL at the lateral lip (LL) of the linea aspera to form a common origin. In some cases (10 of 33), the muscle belly and origin of the VI were much smaller than those in the typical cases; the origin of the VI attached only to the anterior surface of the femur and did not contact the LL. In addition, the muscle belly of the VI was narrow and almost corresponded to the width of the femoral shaft. The isolated muscle specimen is a useful tool for analyzing individual muscle structures, which can be difficult to observe by routine dissection. Using this method, it became clear that the VI is more structurally diverse in its origin than the VL and VM. Clin. Anat. 30:98-105, 2017. © 2016 Wiley Periodicals, Inc.

Anatomic characterization of the humeral nutrient artery: Application to fracture and surgery of the humerus.

Anatomic characterization of the humeral nutrient artery varies among the several textbooks on human anatomy. To clarify the anatomic characteristics of the humeral nutrient artery, we reexamined its origin and course by cadaveric dissection. In typical cases, one prominent nutrient foramen was situated on the anteromedial surface of the humeral shaft, and the nutrient canal distally penetrated the cortical bone layer. The humeral nutrient artery originated from the brachial artery below the level of the nutrient foramen as a short ascending branch. On reaching near the nutrient foramen, the humeral nutrient artery formed a hairpin loop on the periosteum to enter into the nutrient foramen. In some cases, an accessory nutrient foramen was also found near the groove for the radial nerve on the posterior surface of the humerus. This accessory nutrient foramen received an accessory humeral nutrient artery that originated from the radial collateral artery. The present findings corresponded well with the descriptions in the anatomy textbooks published in English-speaking countries. However, textbooks published in German-speaking countries describe only one type of humeral nutrient artery, the branch of the profunda brachii artery. Terminologia Anatomica, the international standard in human anatomic terminology, most likely adopted the description in the German anatomy textbooks, and thus, it is necessary to correct the position of the humeral nutrient artery in the hierarchy of Terminologia Anatomica for accurate morphological description. Clin. Anat. 30:978-987, 2017. © 2017 Wiley Periodicals, Inc.

Application of shear wave elastography for the gastrocnemius medial head to tennis leg.

Muscle strain of the gastrocnemius medial head mainly occurs at the musculotendinous junction (MTJ), and stiffness is a risk factor. Shear wave elastography (SWE) measures elasticity by determining the propagation velocity. The aim of this study was to measure the elasticity of the normal muscle and aponeurosis in the MTJ of the gastrocnemius medial head using SWE, thus obtaining information relevant to muscle strain at this point. Forty-one volunteers (82 legs) were recruited and the gastrocnemius medial heads were examined at four points: three on the aponeurosis, namely at the center of the MTJ (Central), 10 mm proximal to it (Proximal) and 10 mm distal to it (Distal); and at one on the muscle belly (Muscle). The measurements were compared among the points, between males and females, and between younger and middle-aged subjects. Correlations between the elastic modulus and age were also examined. The elastic moduli at Proximal, Central, Distal, and Muscle were 2.82 ± 0.53 m/s, 3.43 ± 0.83 m/s, 4.83 ± 1.56 m/s, and 2.25 ± 0.43 m/s, respectively. These values differed significantly among the points of the aponeurosis, Distal having the highest modulus followed by Central. The elastic moduli were significantly greater in males than females at Distal and Muscle and in younger subjects than middle-aged subjects at Muscle. No significant correlations between elastic modulus and age were observed for any point. SWE could be a feasible method for quantifying the elasticity of muscle and aponeurosis in the MTJ of the gastrocnemius medial head. Clin. Anat. 30:114-119, 2017. © 2016 Wiley Periodicals, Inc.

History of Western Artistic Anatomy in the 19th Century: Prehistory of Artistic Anatomy in Japan.

The study of artistic anatomy was established in the 17th century, and its education techniques were developed in the 19th century and brought to Japan in the Meiji era. Books of artistic anatomy published in the 19th century have been collected and classified into three periods. In the early period before 1828, education of artistic anatomy proper was preliminarily tried, and in the middle period before 1869, new educational methods were invented to adapt the education in the curriculum of the artistic academy. In the late period, various educational methods of artistic anatomy were combined and systematized to provide modem educational materials which are still in use. Medical illustration was developed in the 20th century, and is clearly distinguished from artistic anatomy. The present study reveals the genealogy of Western artistic anatomy as well as the historical background of artistic anatomy in Japan.

Lumbar artery branches coursing vertically over the intervertebral discs of the lower lumbar spine: an anatomic study.

PURPOSE: Bleeding from the lumbar artery is a potential complication during the transpsoas approach to the lower lumbar intervertebral discs. In this anatomic study, the morphological relationships between the branches of the lumbar artery and the lower intervertebral disc were investigated to assess the risk of injury to the branches of the lumbar segmental arteries. METHODS: We studied 88 sites (86 lumbar arteries) at the third and fourth lumbar vertebrae bilaterally in 22 formalin-fixed cadavers. The branches of the lumbar artery coursing along the lateral sides of the lower intervertebral disc [muscular branch, anastomotic branch, and branch supplying the spinal nerve and plexus (BSNP)] and the iliolumbar artery running upward over the L4-5 disc were identified. Branches crossing the intervertebral discs vertically were evaluated. RESULTS: Muscular branches with a lumen structure longer than 2 cm coursed vertically over the middle third of the intervertebral disc in 3 of 88 sites (3.4 %). Anastomotic branches ran downward in 13 of 88 (14.8 %), and iliolumbar arteries ran upward on the posterior third of the lateral sides of the disc in 2 of 88 (2.3 %). BSNPs ran downward through the posterior third of the disc at 18 of 88 sites (20.5 %). Overall, the arterial branches coursed vertically over the posterior third of the lateral sides of the intervertebral discs in approximately 30 % of subjects. CONCLUSIONS: Lumbar artery branches coursed vertically over the middle third and the posterior third of the lateral sides of the intervertebral discs in approximately 3 and 30 % of subjects, respectively.

Reference data on muscle volumes of healthy human pelvis and lower extremity muscles: an in vivo magnetic resonance imaging feasibility study.

PURPOSE: Muscle volumes are of crucial interest when attempting to analyze individual physical performance and disease- or age-related alterations in muscle morphology. However, very little reference data are available in the literature on pelvis and lower extremity muscle volumes originating from healthy and young individuals. Furthermore, it is of interest if representative muscle volumes, covering large anatomical regions, can be obtained using magnetic resonance imaging (MRI) in a setting similar to the clinical routine. Our objective was therefore to provide encompassing, bilateral, 3-T MRI-based datasets on muscle volumes of the pelvis and the lower limb muscles. METHODS: T1-weighted 3-T MRI records were obtained bilaterally from six young and healthy participants. Three-dimensional volumes were compiled from 28 muscles and muscle groups of each participant before the muscle volumes were computed. RESULTS: Muscle volumes were obtained from 28 muscles and muscle groups of the pelvis and lower extremity. Volumes were larger in male than in female participants. Volumes of the dominant and non-dominant sides were similar in both genders. The obtained results were in line with volumetric data obtained from smaller anatomical areas, thus extending the available datasets. CONCLUSIONS: This study provides an encompassing and feasible approach to obtain data on the muscle volumes of pelvic and limb muscles of healthy, young, and physically active individuals. The respective data form a basis to determine effects of therapeutic approaches, progression of diseases, or technical applications like automated segmentation algorithms applied to different populations.