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The cisterna chyli is a lymphatic structure found at the caudal end of the thoracic duct that receives lymph draining from the abdominal and pelvic viscera and lower limbs. In addition to being an important landmark in retroperitoneal surgery, it is the key gateway for interventional radiology procedures targeting the thoracic duct. A detailed understanding of its anatomy is required to facilitate more accurate intervention, but an exhaustive summary is lacking. A systematic review was conducted, and 49 published human studies met the inclusion criteria. Studies included both healthy volunteers and patients and were not restricted by language or date. The detectability of the cisterna chyli is highly variable, ranging from 1.7 to 98%, depending on the study method and criteria used. Its anatomy is variable in terms of location (vertebral level of T10 to L3), size (ranging 2–32 mm in maximum diameter and 13–80 mm in maximum length), morphology, and tributaries. The size of the cisterna chyli increases in some disease states, though its utility as a marker of disease is uncertain. The anatomy of the cisterna chyli is highly variable, and it appears to increase in size in some disease states. The lack of well-defined criteria for the structure and the wide variation in reported detection rates prevent accurate estimation of its natural prevalence in humans.

The mRNA COVID vaccines are only licensed for intramuscular injection but it is unclear whether successful intramuscular administration is required for immunogenicity.In this observational study, eligible adults receiving their first ComirnatyParticipants (n = 402) had a mean age of 34.7 years, BMI 29.1 kg/mA 25 mm needle length is likely to be inadequate to ensure vaccine deposition within the deltoid muscle in a small proportion of adults. Vaccine-induced spike antibody titres were comparable in those vaccinated with a needle of sufficient versus insufficient length suggesting deltoid muscle deposition may not be required for an adequate antibody response to mRNA vaccines.

The thoracic duct (TD) drains most of the body's lymph back to the venous system via its lymphovenous junction (LVJ), playing a pivotal role in fluid homeostasis, fat absorption and the systemic immune response. The respiratory cycle is thought to assist with lymph flow, but the precise mechanism underpinning terminal TD lymph flow into the central veins is not well understood. The aim of this study was to use ultrasonography (US) to explore the relationship between terminal TD lymph flow, the respiratory cycle, and gravity. The left supraclavicular fossa was scanned in healthy non-fasted volunteers using high-resolution (13-5 MHz) US to identify the terminal TD and the presence of a lymphovenous valve (LVV). The TD's internal diameter was measured in relation to respiration (inspiration vs. expiration) and body positioning (supine vs. Trendelenburg). The terminal TD was visualized in 20/33 (61%) healthy volunteers. An LVV was visualized in only 4/20 (20%) cases. The mean terminal TD diameter in the supine position was 1.7 mm (range 0.8-3.1 mm); this increased in full inspiration (mean 1.8 mm, range 0.9-3.2 mm, p < 0.05), and in the Trendelenburg position (mean 1.8 mm, range 1.2-3.1 mm, p < 0.05). The smallest mean terminal TD diameter occurred in full expiration (1.6 mm, range 0.7-3.1 mm, p < 0.05). Respiration and gravity impact the terminal TD diameter. Due to the challenges of visualizing the TD and LVJ, other techniques such as dynamic magnetic resonance imaging will be required to fully understand the factors governing TD lymph flow.

Introduction The bell-clapper deformity (BCD) predisposes to intravaginal torsion (IVT) and is classically bilateral. The precise pathological definition of what constitutes a BCD is not clear. The current study aims to clarify the specific anatomic details of this anomaly. Methods A systematic review was performed utilizing the PRISMA principles. Studies are presented chronologically based on their level of evidence. They are further divided into study types: autopsy and operative studies of acute torsion, intermittent torsion and studies of the contralateral testis in vanishing testis. Results The bell-clapper deformity is best defined by complete investment of the testis, epididymis and a length of the spermatic cord by the tunica vaginalis. Based on autopsy studies the rate of BCD in scrotal testis varied from 4.9% to 16%; with bilaterality in 66%–100%. In cases of acute IVT bilaterality was noted in 54%–100%. The most disparate results were in cases of testicular regression syndrome where contralateral BCD was noted in 0%–87% of cases. Conclusion We suggest future studies employ the strict anatomical definition above. As there is evidence of age-dependent investment of the testes, it will be important to develop age-standardized measurements of intravaginal length of spermatic cord. This critical morphometric measurement will allow a better understanding of the risk of IVT. Level of evidence Systematic review of diagnostic studies: lowest level of evidence of included manuscripts Level IV (case–control studies with a poor reference standard).

Objectives: The elaborate morphometry of the human trapezius muscle facilitates its involvement in numerous active movements of the shoulder girdle and passive stabilization of the upper extremity. Despite its functional importance throughout the lifespan, little is known about the 3D architecture of trapezius at any post-natal timepoints. Accordingly, the aim of this preliminary cadaveric study was to digitize, quantify, model, and compare the 3D architecture of trapezius at two temporal extremes: infancy and adulthood. Methods: We examined trapezius in two female formalin-embalmed cadavers, aged 6 months and 72 years, respectively. We meticulously dissected each muscle, allowing us to digitize and model the comprehensive muscle architecture in situ at the fiber bundle level. We quantified standard architectural parameters to facilitate comparison between each functional partition of trapezius (i.e., descending, transverse, ascending) and proportionally between the infant and adult specimens. Results: We found markedly different patterns in fiber bundle length range, physiological cross-sectional area, and muscle volume within and between muscles. Notably, the proportional physiological cross-sectional area of the ascending and descending partitions was equal (1:1) in the infant, in contrast to 3:1 in the adult. The transverse partitions were proportionally similar, accounting for over half of the whole muscle physiological cross-sectional area in both specimens. Conclusion: This study provides preliminary insights into infant and adult trapezius architecture at an unparalleled level of detail and precision. The quantifiable architectural differences appear to coincide with functional development-a notion that warrants further investigation in larger samples and with longitudinal approaches.

The paranasal sinuses (maxillary, frontal, ethmoid, and sphenoid sinuses) are complex anatomical structures. The development and growth of these have been investigated utilizing a number of different methods ranging from cadaveric analysis to modern cross sectional imaging with 3D modeling. An understanding of normal pediatric paranasal sinus embryology and development enables us to better determine when pathology may be affecting the normal developmental process. Cystic fibrosis, chronic sinusitis, deviated nasal septum and cleft lip and palate are some of the conditions which have been shown to effect paranasal sinus development to varying degrees. Functional endoscopic sinus surgery (FESS) is becoming increasingly common and an understanding of sinus anatomy together with when periods of rapid growth occur during childhood is important clinically. Although concerns have been raised regarding the impact of FESS on facial growth, there is limited evidence of this in regards to either changes in anthropomorphic measurements or clinical assessments of symmetry post operatively.

Lingual frenotomy has become an increasingly common surgical procedure, performed for a broad range of indications from birth through adulthood. This study utilizes histology to define the structure and tissue composition of the lingual frenulum and floor of mouth (FOM) fascia. En bloc specimens of anterior tongue, lingual frenulum, and FOM tissues were harvested from ten embalmed adult cadavers. An additional three fresh tissue cadaveric specimens were frozen with the tongue supported in an elevated position, to enable harvesting and paraffin embedding of the elevated lingual frenulum as a discrete specimen. All 13 specimens were prepared as ten-micron coronal sections using stains to determine the general morphology of the lingual frenulum, its relationship to neighbouring structures (Mason’s Trichrome), presence of elastin fibers (Verhoeff-van Gieson), and collagen typing (Picrosirius Red). Our results have shown a submucosal layer of fascia spanning horizontally across the FOM was present in all specimens, with variability in fascial thickness and histologic composition. This FOM fascia suspends the sublingual glands, vessels, and genioglossus from its deep surface. The elevated lingual frenulum is formed by a central fold of this FOM fascia together with the overlying oral mucosa with variability in fascial thickness and composition. With tongue elevation, the fascia mobilizes to a variable extent into the fold forming the frenulum, providing a structural explanation for the individual variability in lingual frenulum morphology seen in clinical practice.

This study assessed the intra-acquirer, intra- and inter-processor reliability, and validity of the in vivo assessment of the medial gastrocnemius (MG), lateral gastrocnemius (LG) and soleus (SOL) muscle volumes using freehand 3D ultrasound (3DUS) in typically developing infants. Reliability assessments of freehand 3DUS were undertaken in infants across three ages groups: three, six and twelve months of age, with validity testing completed against magnetic resonance imaging (MRI) in infants at 3 months of age. Freehand 3DUS scanning was carried out by a single acquirer, with two independent processors manually segmenting images to render volumes. MRI images were segmented independently by a separate processor, with the volumes compared to those obtained via freehand 3DUS. Reliability was assessed using intraclass correlation (ICC), coefficient of variance (CV) and minimal detectable change (MDC) across each assessment time point. Validity was assessed using the limits of agreement. ICCs for intra-acquirer reliability of the acquisition process for freehand 3DUS ranged from 0.91 to 0.99 across all muscles. ICCs for intra-processor and inter-processor reliability for the segmentation process of freehand 3DUS ranged from 0.80 to 0.98 across all muscles. Acceptable levels of agreement between muscle volume obtained by freehand 3DUS and MRI were found for all muscles; however, freehand 3DUS overestimated muscle volume of MG and LG and underestimate the SOL compared with MRI, with average absolute differences of MG = 0.3 ml, LG = 0.3 ml and Sol = 1.2 ml. Freehand 3DUS is a reliable method for measuring in vivo triceps surae muscle volume in typically developing infants. We conclude that freehand 3DUS is a useful tool to assess changes in muscle volume in response to growth and interventions in infants.

With expanding scope of interventions it becomes mandatory to have correct and evidence-based knowledge of surface anatomy of internal abdominal structures. Information available in text books is derived from work done on cadaveric studies. Current study was designed to provide data of key abdominal surface anatomical landmarks and their variations in living subjects using CT imaging of adult population. Cross-sectional study was conducted using 100 abdominopelvic CT scans of patients of Indian origin. Vertebral levels of origin of celiac trunk varied from T11 to L1/2 intervertebral disc, superior mesenteric artery from T12 to L2, inferior mesenteric artery from L2 to L4 and aortic bifurcation from L3 to L5. Origin of both renal arteries varied between T12 and L2 and the formation of inferior vena cava varied from L3 to L5. Vertebral levels of upper pole of both kidneys ranged from T11 to upper L3. Spleen was related to 9th to 11th ribs in 36% and 10th to 12th ribs in 34% scans. Most common vertebral levels of subcostal plane, planum supracristale and planum intertuberculare noticed were lower L2, L4 and lower L5, respectively. Data derived from imaging investigations of living subjects and variations from the conventional descriptions observed in the current study might be helpful for clinicians.

The lingual frenulum is recognized as having the potential to limit tongue mobility, which may lead to difficulties with breastfeeding in some infants. There is extensive variation between individuals in the appearance of the lingual frenulum but an ambiguous relationship between frenulum appearance and functional limitation. An increasing number of infants are being diagnosed with ankyloglossia, with growing uncertainty regarding what can be considered "normal" lingual frenulum anatomy. In this study, microdissection of four fresh tissue premature infant cadavers shows that the lingual frenulum is a dynamic, layered structure formed by oral mucosa and the underlying floor of mouth fascia, which is mobilized into a midline fold with tongue elevation and/or retraction. Genioglossus is suspended from the floor of mouth fascia, and in some individuals can be drawn up into the fold of the frenulum. Branches of the lingual nerve are located superficially on the ventral surface of the tongue, immediately beneath the fascia, making them vulnerable to injury during frenotomy procedures. This research challenges the longstanding belief that the lingual frenulum is a midline structure formed by a submucosal "band" or "string" and confirms that the neonatal lingual frenulum structure replicates that recently described in the adult. This article provides an anatomical construct for understanding and describing variability in lingual frenulum morphology and lays the foundation for future research to assess the impact of specific anatomic variants of lingual frenulum morphology on tongue mobility. Clin. Anat. 32:824-835, 2019. © 2019 The Authors. Clinical Anatomy published by Wiley Periodicals, Inc. on behalf of American Association of Clinical Anatomists.

There appear to be various patterns of sidedness with relation to the common urogenital malformations observed in pediatric urology. The objective of this statistical review was to synthesize this data and to assess if these patterns are significant.Eighteen urogenital conditions were investigated and for each condition the five largest studies that noted laterality were included. The sidedness of each condition was then analysed for statistical significance.Three conditions had a statistically significant higher proportion on the right side: palpable undescended testis (63%, p = 0.0002), inguinal hernia (59%, p = 0.0001) and hydrocele (60%, p = 0.003). Three conditions were significantly more common on the left side: impalpable undescended testis (59%, p = 0.0008), renal agenesis (54%, p = 0.02) and vesico-ureteric junction obstruction (71%, p 0.0001) while both pelvi-ureteric junction obstruction (62%, p = 0.09) and absent vas deferens (61%, p = 0.11) were trending towards significance.Various urogenital malformations display a predilection for one side. Proximal malformations tend to be more frequently seen on the left side, where as inguinoscrotal malformations are more frequently observed on the right. There is an increasing body of literature regarding aetiological factors for these conditions. However, our current understanding of the pathophysiology of these conditions does not completely explain this pattern of observation.

Introduction: Recent studies have demonstrated an association between maternal supine sleep position and an increased risk of late stillbirth. During late pregnancy, the gravid uterus compresses the inferior vena cava (IVC) when a woman lies in the supine position. The azygos system of veins is the dominant pathway of collateral venous return back to the heart in the event of acute obstruction of the IVC. It is suggested that this pathway provides adequate collateral venous circulation in the event of IVC compression in the supine position during late pregnancy. Objective: Investigate the effect of supine positioning on maternal hemodynamics during late pregnancy and the role of collateral venous circulation. Methods: Ethics approval was obtained and 12 women with singleton pregnancies between 35- and 38-week gestation underwent magnetic resonance imaging in the supine and left lateral decubitus positions using a Skyra 3T system (Siemens). Phase-contrast images were evaluated to measure cardiac output, blood flow through the azygos vein, and blood flow through the abdominal aorta (AA) and IVC at two levels: at the level of aortic bifurcation and immediately above the renal veins. Results: The supine position was associated with a 16.4% reduction in cardiac output when compared to the left lateral position. In addition, blood flow through the IVC decreased at its origin by 85.3% and by 44.4% at the level of the renal veins. Blood flow through the azygos vein increased in the supine position by 220%. Blood flow through the AA at the level of the renal veins did not differ significantly; however, it is reduced by 32.3% at the level of the aortic bifurcation. Conclusions: Women in late pregnancy experience an increase in collateral venous blood flow when lying supine, likely as a response to marked compression of the IVC in this position. However, cardiac output and aortic blood flow were found to decrease while in the supine position.

OBJECTIVE. The objective of our study was to retrospectively determine the anatomic distribution of chest wall ectopic gas resembling pneumoperitoneum (i.e., pseudopneumoperitoneum) and its relatio...

Little information is available on the length of the normal large intestine and its component parts in children. This information would be useful for procedures such as colonoscopy. The aim of this study was to investigate the length of the large intestine and its component parts in New Zealand children. Archival deidentified pediatric supine abdominopelvic computed tomography (CT) scans were retrospectively analyzed. After exclusion criteria, a total of 112 scans (57 males and 55 females) were included in the study and divided into three age groups: 0-2 years (n = 33), 4-6 years (n = 40), and 9-11 years of age (n = 39). The length of the large bowel increased from a mean of 52 cm in children aged

Recent literature has reported an association between maternal supine sleep position and stillbirth during late pregnancy. In this position the gravid uterus almost completely obstructs the inferior vena cava. A small number of women experience supine hypotension, thought to be due in part to inadequate collateral venous circulation. The aim of this paper is to review the literature describing the anatomy of the collateral venous system and in particular the azygos system, the abdominal portion of which has not been well studied. A systematic review was conducted using the electronic databases: Medline, Embase, Scopus, and Google Scholar. Relevant anatomical and radiological literature concerning the azygos system in particular was reviewed. The search was limited to adult human studies only. The collateral venous system can be divided into superficial, intermediate and deep systems. The azygos system in particular provides immediate collateral venous circulation in the event of acute inferior vena caval obstruction. The abdominal portion of this pathway, including the ascending lumbar vein, has not been well studied and there are certain variations that can render it ineffective. In conclusion, the collateral venous system provides an alternative route for blood to flow back to the systemic circulation when acute occlusion of the inferior vena cava occurs in the supine position during late pregnancy. However, certain anatomical variations can render this pathway ineffective, and this could have implications for the development of supine hypotension and stillbirth in late pregnancy. Clin. Anat. 30:1087-1095, 2017. © 2017 Wiley Periodicals, Inc.

Accurate knowledge of surface anatomy is fundamental to safe clinical practice. A paucity of evidence in the literature regarding thoracic surface anatomy in children was identified. The associations between surface landmarks and internal structures were meticulously analyzed by reviewing high quality computed tomography (CT) images of 77 children aged from four days to 12 years. The results confirmed that the sternal angle is an accurate surface landmark for the azygos-superior vena cava junction in a plane through to the level of upper T4 from birth to age four, and to lower T4 in older children. The concavity of the aortic arch was slightly below this plane and the tracheal and pulmonary artery bifurcations were even lower. The cardiac apex was typically at the 5th intercostal space (ICS) from birth to age four, at the 4th ICS and 5th rib in 4-12 year olds, and close to the midclavicular line at all ages. The lower border of the diaphragm was at the level of the 6th or 7th rib at the midclavicular line, the 7th ICS and 8th rib at the midaxillary line, and the 11th thoracic vertebra posteriorly. The domes of the diaphragm were generally flatter and lower in children, typically only one rib level higher than its anterior level at the midclavicular line. Diaphragm apertures were most commonly around the level of T9, T10, and T11 for the IVC, esophagus and aorta, respectively. This is the first study to provide an evidence-base for thoracic surface anatomy in children. Clin. Anat. 30:788-794, 2017. © 2017Wiley Periodicals, Inc.

Ultrasonography is widely practiced in many disciplines. It is becoming increasingly important to design well-structured curricula to introduce imaging to students during medical school. This review aims to analyze the literature for evidence of how ultrasonography has been incorporated into anatomy education in medical school curricula worldwide. A literature search was conducted using multiple databases with the keywords: "Ultrasound OR Ultrasonographic examination*" and "Medical student* OR Undergraduate teaching* OR Medical education*" and "Anatomy* OR Living anatomy* OR Real-time anatomy.*" This review found that ultrasound curricula vary in stage of implementation, course length, number of sessions offered to students as well as staffing and additional course components. Most courses consisted of didactic lectures supplemented with demonstration sessions and/or hands-on ultrasound scanning sessions. The stage of course implementation tended to depend on the aim of the course; introductory courses were offered earlier in a student's career. Most courses improved student confidence and exam performance, and more junior students tended to benefit more from learning anatomy with ultrasound guidance rather than learning clinical examination skills. Students tended to prefer smaller groups when learning ultrasound to get more access to using the machines themselves. Ultrasonography is an important skill, which should be taught to medical students early in their careers as it facilitates anatomical education and is clinically relevant, though further objective research required to support the use of ultrasound education as a tool to improve clinical examination skills in medical students. Clin. Anat. 30:452-460, 2017. © 2017 Wiley Periodicals, Inc.

Surface landmarks in the neck are important for orientations of cervical glands, arteries, veins, nerves, and vertebrae. Recent research suggests some orientations are not correct. What are the cervical landmark orientations in the Chinese population? In this study, two essential cervical anatomy planes, the thyroid cartilage and C7 planes, were assessed in living adult Chinese subjects using computed tomography (CT), and the hyoid, carotid bifurcation, cricoid cartilage, thyroid arteries, and vertebral artery were simultaneously positioned. After excluding patients with distorting pathology, a total of 108 cervical CT scans were examined. The thyroid cartilage plane commonly passed through the C5 (in males) or C4 (in females) vertebral level. The carotid artery bifurcated most commonly at C3 (left) or C4 (right), more than 10 mm above the thyroid cartilage plane bilaterally in most cases. Orientation of the carotid bifurcation according to the body or greater horn of the hyoid was more accurate. The superior thyroid artery was found a finger-breadth below the thyroid cartilage plane, and the inferior thyroid artery in the C7 plane. The inferior border of the cricoid cartilage was most often at C7 (in males) or C6 (in females). The vertebral artery entered the C6 transverse foramen in more than 80% of scans. This reassessment of cervical surface anatomy using modern imaging tools in vivo provides both qualitative and quantitative information for surgeons in clinical practice. Clin. Anat. 30:330-335, 2017. © 2017 Wiley Periodicals, Inc.

The interest in approaches to deliver therapeutics to the lymphatic system has increased in recent years as the lymphatics have been discovered to play an important role in a range of disease states such as cancer metastases, inflammatory and metabolic disease, and acute and critical illness. Therapeutic delivery to lymph has the potential to enhance treatment of these conditions. Currently much of the existing data explores therapeutic delivery to the lymphatic vessels and nodes that drain peripheral tissues and the intestine. Relatively little focus has been given to understanding the anatomy, function and therapeutic delivery to the peritoneal lymphatics. Gaining a better understanding of peritoneal lymphatic structure and function would contribute to the understanding of disease processes involving these lymphatics and facilitate the development of delivery systems to target therapeutics to the peritoneal lymphatics. This review explores the basic anatomy and ultrastructure of the peritoneal lymphatics system, the lymphatic drainage pathways from the peritoneum, and therapeutic and delivery system characteristics (size, lipophilicity and surface properties) that favour lymph uptake and retention after intraperitoneal delivery. Finally, techniques that can be used to quantify uptake into peritoneal lymph are outlined, providing a platform for future studies.

In this case study we present new evidence of a piriformis muscle variant inserting onto the hip joint capsule similar to that described by Tubbs and Salter. The variant was also atypical in that it originated medial to the first anterior sacral foramina and therefore obscured the union of the S1 nerve root and lumbosacral trunk. We believe this is the first instance that this variant has been noted.

The endocrine system behaves with pleasing simplicity, linked by negative and positive feedback loops. These feedback loops originate in the hypothalamus. Controlling, in turn, the anterior and posterior pituitary. There are three main hormone types released in the body, each with a specific way they interact with the cell they control.

Despite being integral to medical and surgical practice, pediatric anatomy has remained relatively neglected except for a few landmark works. Neonatal and pediatric anatomy differs structurally and functionally from adult anatomy in many ways. The aim of the current study was to reappraise common abdominal surface landmarks of important structures in infants and children. After cases with related pathologies had been excluded, computer tomography scans of 90 children were divided into three age groups and systematically analyzed. The vertebral levels of the unpaired branches of the abdominal aorta (AA) were recorded. The vertebral level and relationship to the midline of the bifurcation of the AA and the formation of the inferior vena cava were measured. The renal long axes, costal relationships, renal artery vertebral levels, and hilar vertebral levels were measured. The splenic long axis and relationship to the mid-axillary line were also measured. The renal length was disproportionately large in the youngest age group and increased less with age (7.12 cm, 7.85 cm, 8.86 cm). The renal artery was consistently found around L1; the left kidney was related to the 11th and 12th ribs posteriorly, the right kidney only to the 12th rib. The AA bifurcated to the right of the midline in 10% of children. The unpaired visceral branches of the aorta were commonly found at T12 (celiac artery), L1 (superior mesenteric artery), and L3 (inferior mesenteric artery). The current study provides age-standardized surface landmarks and measurements for major abdominal vascular structures and solid organs in normal children. The clinical applications of these data are multiple and diverse.

Surface anatomy is a core component of human anatomy in clinical practice. It allows clinicians to assess patients accurately and quickly; however, recent studies have revealed variability among individuals and ethnicities. The aim of this study is to investigate possible variations in adult thoracic and abdominal surface anatomy landmarks in an Iranian population. This study used 100 thoracoabdominal CT scans (mean age: 47 ± 17 years, age range: 20-77 years, 47% females), noted the most common locations of clinically relevant surface markings, and analyzed correlations between these variables and age or gender. While many common surface markings in Iranians were consistent with the evidence-based literature, there were some differences. In relation to the corresponding segments of the vertebral column, the superior vena cava formation and the lower border of the pleura adjacent to the vertebral column and right kidney tended to be at higher levels in adult Iranians than a Caucasian population. There were also discrepancies between the Iranian population and commonly-referenced medical textbooks and recent evidence-based literature concerning the vertebral levels of the diaphragmatic openings of the esophagus, aorta, and inferior vena cava. This study emphasizes the need to consider evidence-based reappraisals of surface anatomy to guide clinical practice. Much of our current knowledge of surface anatomy is based on older studies of cadavers rather than living people, and does not take ethnic and individual variations into consideration.

The influence of ankle kinematics and plantar pressure from mid-range barefoot running on T2 relaxation times of tibiotalar cartilage is unknown. This study aimed to quantitatively evaluate the T2 relaxation time of tibiotalar cartilage and ankle biomechanics following 5 km barefoot running. Twenty healthy runners (who had no 5 km barefoot running experience) underwent 3.0-Tesla magnetic resonance (MR) scans and assessment of running gait before and after 5 km barefoot running. Participants were divided into two groups consisting of marathon-experienced (n = 10) and novice (n = 10) with equal number of males and females in each group. Three musculoskeletal radiologists measured T2 relaxation times in 18 regions of the ankle cartilage: anterior zone, central zone, and posterior zone, or lateral, middle, and medial sections in the sagittal plane. Three-dimensional ankle kinetics, kinematics, and plantar pressure were all also assessed during barefoot running. In the novice group, the T2 relaxation time in the posterior zone of tibial cartilage (p = 0.001) and lateral section in both tibial (p = 0.02) and talar (p = 0.02) cartilage were significantly increased after barefoot running. Ankle kinematics exhibited significant changes in females. Plantar loading was shifted from the medial to lateral aspect after running. This included a significant reduction in the loading under the toes and the 1st, 2nd and 3rd metatarsals, with a significant increase under the 4th and 5th metatarsals and lateral midfoot. The results suggest that plantar pressure may directly lead to local increases in cartilage T2 signal, which was not associated with changes in ankle kinematics.

Nerve injuries usually present as pain, numbness, or weakness, and can have devastating consequences for patients. Procedures that are common in primary care can cause nerve injury. Iatrogenic nerve injuries are largely preventable by understanding nerve anatomical course and surface anatomy, and the risky interventions and regions. Most knowledge of nerve anatomical course is derived from early work on cadaver dissection, but modern imaging techniques more accurately map nerve anatomical course in living bodies. We provide an overview of nerve injuries in primary care, discuss updated nerve anatomical course and surface anatomy based on modern radiological evidence, and make recommendations to guide safer interventions in primary care. In New Zealand’s primary care treatment injury claims dataset there were 69 nerve injuries over 4 years (2% of primary care injuries).1 Venepuncture was the leading cause of nerve injury (27; 39%), followed by intramuscular injection (17; 25%), and steroid injection (15; 22%). Venepuncture injured the cutaneous nerve of the forearm (14), and the median (9) and radial (4) nerves; intramuscular injections injured the sciatic (11), lateral cutaneous (3), and axillary (3) nerves; steroid injections injured the median (12, carpal tunnel) and ulnar (3, medial epicondyle) nerves; intravenous cannulation in the forearm injured the superficial radial nerve (4); and minor surgical procedures injured the spinal accessory (3), common fibular (1), sural (1), and ilioinguinal nerves (1). Most nerve injuries were minor, but 17 (25%) were assessed as having major or serious potential consequences. …

Pediatric emergency physicians, pediatric critical care specialists, and pediatric surgeons perform central venous catheterization in many clinical settings. Complications of the procedure are not uncommon and can be fatal. Despite the frequency of application, the evidence-base describing the surface landmarks involved is missing. The aim of the current study was to critically investigate the surface markings of the central venous system in children. The superior vena cava/right atrial (SVC/RA) junction, superior vena cava (SVC) formation, and brachiocephalic vein (BCV) formation were examined independently by two investigators. Three hundred computed tomography (CT) scans collected across multiple centers were categorized by age group into: 0-3 years, 4-7 years, and 8-11 years. Scans with pathology that distorted or obscured the regional anatomy were excluded. The BCV formation was commonly found behind the ipsilateral medial clavicular head throughout childhood. This contrasts with the variable levels of SVC formation, SVC length, and SVC/RA junction. In the youngest group, SVC formation was most commonly at the second costal cartilage (CC), but moved to the first CC/first intercostal space (ICS) as the child grew. The SVC/RA junction was at the fourth CC in the youngest group and moved to the third CC/third ICS as the child grew. This study demonstrates the variable anatomy of SVC formation and the SVC/RA junction with respect to rib level. This variability underscores the unreliability of surface anatomical landmarks of the SVC/RA junction as a guide to catheter tip position.

The inguinoscrotal region is one of the most common areas operated on in pediatric surgery. Despite this, the surface anatomy of the pediatric inguinal canal is variably defined. The aim of the current systematic review is to evaluate the development and surface anatomy of the pediatric inguinal canal. A systematic review of inguinal canal anatomy in children was conducted using the electronic databases: Medline, PubMed, Scopus, and Google Scholar. Relevant anatomical measurements and relationships were reviewed. The anatomical structures forming the walls of the inguinal canal were identified in fetuses as early as 8-10 weeks gestation. No studies addressed the developmental basis of this early defect in the lower anterior abdominal. Later gonadal development and descent has a defined role. In vivo measurements of children carried out during open surgery are inconsistent. Some studies showed rapid growth velocity of the length of the inguinal canal up to 2 years of age (with height and growth of the bony pelvis) before plateauing, while others suggested no increase in canal length prior to 10 years of age. The position of the deep inguinal ring was equally unclear; some studies suggested this was medial to the midpoint of the inguinal ligament. No studies described the position of the superficial ring, challenging the assumption that the rings are superimposed in the neonate. The dearth of studies analyzing pediatric inguinal anatomy means that changes in the position of the rings with respect to the lengthening of the canal remain unclear.

No anatomy text specifically describes the course of the sciatic nerve (SN) in the gluteal region in children. Anatomical information is largely derived from cadaveric studies of adults, so accurate anatomical information about the location of the SN in children is required. The aim of this study is to assess the surface anatomy of the SN in children using computed tomography (CT). After excluding studies with pelvic pathology, 75 CT scans were analyzed. Three groups were selected for analysis (0-2, 4-6, and 8-10 years). The position of the SN was measured between the posterior superior iliac spine (PSIS) and the ischial tuberosity (IT) and between the IT and the greater trochanter (GT) using 3-dimensional images. In the 0-2 age group, the SN crossed the middle third of a line between the PSIS and the IT in 94% and the GT and the IT in 80% of cases. In the 4-6 age group, the SN crossed the middle third of a line between the PSIS and the IT in 96% and the GT and the IT in 87%. In the 8-10 age group, the SN crossed the middle third of a line between the PSIS and the IT in 100% and the GT and the IT in 71%. The findings indicate that the SN in children is most accurately located in the middle third along a line drawn from the PSIS to the IT and the GT to the IT. Our study is the first to provide anatomical CT data from living children to guide interventions in the gluteal region.

The duodenojejunal flexure (DJF) is an important surgical landmark that enables the pediatric surgeon to establish whether normal intestinal rotation has occurred. The degree of variation in the position of the DJF has not been studied in the pediatric population, and there have been only limited studies on adults. The aim of the present study was to determine the position and relationships of the DJF in infants and children utilizing cross-sectional imaging. Computer tomography scans of 120 children were divided into three age groups and systematically analyzed. The DJF position was measured in relation to the vertebral body level, midline, anterior-posterior distance from the vertebral body, transpyloric plane, and mesenteric vessels. The position of the third part of the duodenum and the length of the mesenteric root were also determined. There was considerable variation in the DJF position with respect to the above landmarks in all three age groups. The vertebral body level of the DJF was centered on L1, but ranged between T11 and L3. In 3% of children with normal rotation the SMA/SMV relationship was abnormal. The third part of the duodenum was consistently found to be retromesenteric. The length of the mesenteric root ranged from 7 to 22 cm, and generally lengthened with increasing age. Owing to its variable position in infants and children, the DJF on its own may not be a reliable landmark for establishing normal intestinal rotation. Assessing for normal rotation is multifaceted and further comparative studies are required to characterize the anatomical features of normal and abnormal rotation.

Accurate surface anatomy is essential for safe clinical practice. There are numerous inconsistencies in clinically important surface markings among and within contemporary anatomical reference texts. The aim of this study was to investigate key thoracic and abdominal surface anatomy landmarks in living Chinese adults using computed tomography (CT). A total of 100 thoracic and 100 abdominal CT scans were examined. Our results indicated that the following key surface landmarks differed from current commonly-accepted descriptions: the positions of the tracheal bifurcation, azygos vein termination, and pulmonary trunk bifurcation (all below the plane of the sternal angle at vertebral level T5-T6 in most individuals); the superior vena cava formation and junction with the right atrium (most often behind the 1st and 4th intercostal spaces, respectively); and the level at which the inferior vena cava and esophagus traverse the diaphragm (T10 and T11, respectively). The renal arteries were most commonly at L1; the midpoint of the renal hila was most frequently at L2; the 11th rib was posterior to the left kidney in only 29% of scans; and the spleen was most frequently located between the 10th and 12th ribs. A number of significant sex- and age-related differences were noted. The Chinese population was also compared with western populations on the basis of published reports. Reappraisal of surface anatomy using modern imaging tools in vivo will provide both quantitative and qualitative evidence to facilitate the clinical application of these key surface landmarks.

Anatomy students are often confused by multiple names ascribed to the same structure by different clinical disciplines. Increasingly, sonography is being incorporated into clinical anatomical education, but ultrasound textbooks often use names unfamiliar to the anatomist. Confusion is worsened when ultrasound names ascribed to the same structure actually refer to different structures. Consider the sonographic main lobar fissure (MLF). The sonographic MLF is a hyper-echoic landmark used by sonographers of the right upper quadrant. Found in approximately 70% of people, there is little consensus on what the sonographic MLF is anatomically. This structure appears to be related to the main portal fissure (aka principal plane of the liver or principal hepatic fissure), initially described by anatomists and surgeons as in intrahepatic division along the middle hepatic vein which in essence divides the territories of the left and right hepatic arteries and biliary systems. By exploring the relationship between the main portal fissure and the sonographic MLF in cadaveric livers ex vivo, the data suggest the sonographic MLF is actually an extrahepatic structure that parallels the rim of the main portal fissure. The authors recommend that this structure be renamed the "sonographic cystic pedicle," which includes the cystic duct and ensheathing fat and blood vessels. In the context of the redefined underlying anatomy, the absence of the sonographic cystic pedicle due to anatomic variation may serve an important clinical role in predicting complications from difficult laparoscopic cholecystectomies and is deserving of future study.

Accurate knowledge of surface anatomy is fundamental to safe clinical practice. A paucity of evidence in the literature regarding thoracic surface anatomy in children was identified. The associations between surface landmarks and internal structures were meticulously analyzed by reviewing high quality computed tomography (CT) images of 77 children aged from four days to 12 years. The results confirmed that the sternal angle is an accurate surface landmark for the azygos-superior vena cava junction in a plane through to the level of upper T4 from birth to age four, and to lower T4 in older children. The concavity of the aortic arch was slightly below this plane and the tracheal and pulmonary artery bifurcations were even lower. The cardiac apex was typically at the 5

Ultrasonography is widely practiced in many disciplines. It is becoming increasingly important to design well-structured curricula to introduce imaging to students during medical school. This review aims to analyze the literature for evidence of how ultrasonography has been incorporated into anatomy education in medical school curricula worldwide. A literature search was conducted using multiple databases with the keywords: "Ultrasound OR Ultrasonographic examination*" and "Medical student* OR Undergraduate teaching* OR Medical education*" and "Anatomy* OR Living anatomy* OR Real-time anatomy.*" This review found that ultrasound curricula vary in stage of implementation, course length, number of sessions offered to students as well as staffing and additional course components. Most courses consisted of didactic lectures supplemented with demonstration sessions and/or hands-on ultrasound scanning sessions. The stage of course implementation tended to depend on the aim of the course; introductory courses were offered earlier in a student's career. Most courses improved student confidence and exam performance, and more junior students tended to benefit more from learning anatomy with ultrasound guidance rather than learning clinical examination skills. Students tended to prefer smaller groups when learning ultrasound to get more access to using the machines themselves. Ultrasonography is an important skill, which should be taught to medical students early in their careers as it facilitates anatomical education and is clinically relevant, though further objective research required to support the use of ultrasound education as a tool to improve clinical examination skills in medical students. Clin. Anat. 30:452-460, 2017. © 2017 Wiley Periodicals, Inc.

Surface landmarks in the neck are important for orientations of cervical glands, arteries, veins, nerves, and vertebrae. Recent research suggests some orientations are not correct. What are the cervical landmark orientations in the Chinese population? In this study, two essential cervical anatomy planes, the thyroid cartilage and C7 planes, were assessed in living adult Chinese subjects using computed tomography (CT), and the hyoid, carotid bifurcation, cricoid cartilage, thyroid arteries, and vertebral artery were simultaneously positioned. After excluding patients with distorting pathology, a total of 108 cervical CT scans were examined. The thyroid cartilage plane commonly passed through the C5 (in males) or C4 (in females) vertebral level. The carotid artery bifurcated most commonly at C3 (left) or C4 (right), more than 10 mm above the thyroid cartilage plane bilaterally in most cases. Orientation of the carotid bifurcation according to the body or greater horn of the hyoid was more accurate. The superior thyroid artery was found a finger-breadth below the thyroid cartilage plane, and the inferior thyroid artery in the C7 plane. The inferior border of the cricoid cartilage was most often at C7 (in males) or C6 (in females). The vertebral artery entered the C6 transverse foramen in more than 80% of scans. This reassessment of cervical surface anatomy using modern imaging tools in vivo provides both qualitative and quantitative information for surgeons in clinical practice. Clin. Anat. 30:330-335, 2017. © 2017 Wiley Periodicals, Inc.

You are assisting your consultant during a lymph node biopsy of the posterior triangle of the neck.

The surface anatomy of the sciatic nerve (SN) in the gluteal region is clinically important (e.g., intramuscular injection). Anatomy texts describe the nerve in relation to the posterior superior iliac spine (PSIS), ischial tuberosity (IT), and greater trochanter (GT) but descriptions are inconsistent. The surface anatomy of the SN was determined in relation to these bony landmarks using computed tomography (CT) scans in living adults. One hundred consecutive adult pelvic CT scans (36 females, mean age 76 years) were available for dual consensus analysis. A further 19 adults (9 females, mean age 74 years) underwent pelvic CT scans in both prone and supine positions. The surface projection of the SN along a line between the PSIS and IT and between the IT and GT was measured. The SN was identified in 95% of scans at a mean of 5.2 ± 1.0 cm from the PSIS and 11.4 ± 1.1 cm from the IT. The SN was a mean of 5.8 ± 0.8 cm from the IT and 6.2 ± 1.0 cm from the GT. There were no significant differences in mean positions of the nerve between sides and sexes. A small but clinically irrelevant difference in the surface marking of the SN was found between supine and prone positions with respect to the GT and IT but not in relation to the PSIS and IT. In living adults, the SN lies approximately one-third of the way along a line between the PSIS and IT and half way between the GT and IT.