International consensus for a dissection room quality system (DRQS): A Delphi panel study

Dissection Rooms (DRs) are key facilities that allow teaching and research on human anatomy, where students and researchers work with human bodies to acquire, increase, or create new knowledge. Usually, DRs work with a Body Donation Program (BDP), where living donors bequeath their bodies for use in teaching and research after they expire. Despite DRs being part of universities worldwide, no common guidelines, regulations, or quality management systems (QMS) exist that could be applied to different countries. With that purpose in mind, we aimed to develop a QMS that could be applied to DRs globally, using a Delphi panel to achieve consensus about the items that should constitute the QMS. The panel was constituted by 20 anatomy professors from 20 different countries, and the 167 standards to create the rules or guidelines that constitute the QMS were divided in five categories: direction, body donation, students, instructors, and research. After two rounds of revisions, 150 standards were considered "essential" or "important" by more than 70% of the participants, thus being incorporated to the Dissection Room Quality System (DRQS). The results of this panel represent a minimum list of items of the DRQS for improving the functioning of DRs globally.

An unusual origin of a papillary muscle of the right ventricle

Knowledge of anatomical variations of the heart are important to cardiac surgeons, cardiologists, and radiologist. During routine dissection of a 77-year-old male cadaver, we observed an unusual origin of a papillary muscle of the right ventricle arising from the atrioventricular aspect of the moderator band. This papillary muscle was 6.7mm long and 2.6mm wide. It gave rise to two chordae tendineae: one to the inferior (posterior) papillary muscle of the right ventricle and one directly to the inferior (posterior) leaflet of the tricuspid valve. Variants of the internal anatomy of the heart as exemplified in the present case report should be born in mind during image interpretation and invasive procedures of the right ventricle of the heart.

How to write an umbrella review? A step-by-step tutorial with tips and tricks

The number of meta-analyses (MA) and systematic reviews (SR) on various medical issues has increased during the last two decades. The MA and SR results may differ from one another due to a number of factors such as inaccurate or diverse searches through the databases, discrepancies in the extraction process or in statistical analysis, among others. Some results may even contradict one another, resulting in confusion among readers. Umbrella reviews (UR) have allowed the collection of all available data on a medical issue into one concise study, making it the source of evidence-based medical knowledge to the highest degree. Furthermore, UR can resolve those problems by collecting all data and taking into account both MA and SR, making it the superior tool for physicians. Although the pros of UR are clear and the overall popularity of these types of study has increased tremendously, there is no available step-by-step guide on how to conduct one. Therefore, the objective of the present study was to provide researchers with a detailed tutorial on how to conduct an UR. UR represent the next major step in the advancement of evidence-based medicine, with great practical potential for physicians looking for the most up-to-date data on their topic of interest. We hope that our step-by-step guide may be a useful tool for researchers conducting UR in the future.

Branching pattern of the internal iliac artery accompanied by a venous anastomosis: rare vascular variations

The ability to navigate the complex and often deceptive branching patterns of the internal iliac artery can be decisive in planning and performing surgeries within the lesser pelvis. The following case report presents a peculiar quadruple division of the internal iliac artery, accompanied by a venous anastomotic structure. Apart from the posterior and anterior trunks, the superior vesicle and iliolumbar arteries arose independently from the internal iliac artery. The division was surrounded by a venous oval, compressing certain branches and potentially complicating surgical access. Due to the uncommon course of the internal iliac artery and the presence of the anastomosis, a possible nerve root compression has been identified. Both clinical significance and classification method of the case are discussed. Knowledge of this anatomical variation is valuable for both diagnosis and surgery, especially within the specialties of urology, gynaecology and general surgery.

Five-headed superior omohyoid

The omohyoid is an infrahyoid muscle with two bellies. It is responsible for lowering and positioning of the hyoid bone. It is morphologically variable in the origin, insertion and morphology of its bellies. Quantitative variations of the superior belly of the omohyoid muscle are not common. We present a case of a five-headed superior omohyoid, and a short clinical review related to this muscle. All the bellies had their origin in an intermediate tendon and were attached to the hyoid bone. The volume of its superior part was greater than usual. Knowledge of the anatomy of this muscle is important, especially for surgeons operating in the anterolateral neck region.

Variant origin of three main coronary ostia from the right sinus of Valsalva: report of a rare case

Observing anomalies in the origin of the coronary arteries is a rare but recognised scenario during coronarography. All the major coronary arteries originating from the right sinus of Valsalva is an extremely rare anomaly, its reported incidence being 0.008% in angiographic studies. Most coronary artery variations are benign and are therefore found accidentally or postmortem. However, some anomalies in the origin of the coronary arteries are associated with myocardial ischaemia and a higher risk of sudden cardiac death. Herein, we report a sporadic case of anomalous origin of the coronary arteries, in which the right coronary artery, anterior interventricular artery and left circumflex artery arise separately from the right sinus of Valsalva, each originating from a separate ostium. Regardless of their low incidence rate, coronary artery anomalies can cause serious technical challenges during coronary angiography and percutaneous interventions because of the unusual location and course of the artery. Echocardiography, computed tomography, and magnetic resonance imaging can be useful in such cases.

The petroclinoid ligament: a meta-analysis of its morphometry and prevalence of mineralization with a review of the literature

BACKGROUND

The petroclinoid ligament (PCL) is an important structure in the petroclival region. The anatomy of the PCL and its relationship with the surrounding structure is highly variable. The aim of this study was to estimate the morphometry, prevalence of mineralization, and anatomy of the PCL. To achieve this, the authors carried out a meta-analysis, including all studies that report extractable data on the PCL.

MATERIALS AND METHODS

Major online medical databases such as PubMed, Scopus, ScienceDirect, Web of Science, SciELO, BIOSIS, Current Content Connect, Korean Journal Database, and Russian Citation Index were searched to gather all studies regarding the anatomical characteristics, morphometry, and relationship with the anatomical surroundings of the PCL.

RESULTS

A total of 25 studies were included in this meta-analysis. Data were gathered and analysed in eight categories: (1) mineralization of the PCL, (2) relationship of the abducens nerve with the PCL, (3) relationship of the dorsal meningeal artery with the PCL, (4) shape, number, and continuity of the PCL, (5) PCL anterior attachment, (6) PCL anterior attachment point on bone, (7) PCL posterior attachment point on bone, (8) morphometric features of the PCL.

CONCLUSIONS

In conclusion, the authors of the present study believe that this is the most accurate and up-to-date meta-analysis regarding the morphology and mineralization of the PCL. The data provided by the present study may be a useful tool for surgeons performing neurosurgical procedures, such as endoscopic transnasal surgeries. Detailed anatomical knowledge of the petroclival region can surely prevent surgical complications when operating in this area.

A unique variation of a four-bellied digastric muscle named "real quadrigastric muscle": a case report and literature review

From a topographical standpoint, the digastric muscle is key to the formation of several triangles of the neck, which are of the utmost clinical significance. Herein, we present a previously unrecognised variation of the digastric muscle: a quadrigastric muscle with two accessory bellies originating from the body and angle of the mandible and inserting to the intermediate tendon. Three new triangles are demarcated between the four bellies of the aberrant muscle. Detailed knowledge of variations of the digastric muscle, changing the borders and relationships of the topographic triangles, is paramount for radiologists and surgeons operating on the anterior region of the neck.

Clinical significance of morphological variations of the inferior phrenic arteries

The rapid development of sciences such as genetics and molecular biology offers hope that better therapeutic methods can be developed and diagnosis and treatment made more effective. However, we must not forget that the basis for understanding the complex mechanisms of diseases and associated symptoms is knowledge of the relevant location and correlation among organs. In the present study, we focus on the clinical significance of the inferior phrenic artery. The diaphragm is a muscular structure that separates the abdominal and chest cavities. Thanks to this position, the inferior phrenic artery is much more significant than formerly assumed. A rich network of collaterals makes this vessel important in the development of neoplasms and metastases. Knowledge of anatomical variants of the inferior phrenic artery is also crucial for radiological procedures such as embolisation. The main aim of this study is to review the involvement of the inferior phrenic artery in physiological and pathophysiological processes. This work has value for all practicing doctors, especially radiologists and surgeons.

The petrosal artery and its variations: a comprehensive review and anatomical study with application to skull base surgery and neurointerventional procedures

BACKGROUND

The petrosal artery supplies several structures at the skull base and is often the focus of various neurointerventional procedures. Therefore, knowledge of its anatomy and variations is important to surgeons and interventionalists.

MATERIALS AND METHODS

Twenty latex injected cadaveric heads (40 sides) underwent microsurgical dissection of the petrosal artery. Documentation of the course of the artery and its branches were made. Measurements of the petrosal artery's length and diameter were performed using microcallipers.

RESULTS

A petrosal artery was identified on all sides. The mean length and diameter of the artery within the middle cranial fossa was 2.4 cm and 0.38 mm, respectively. Branches included the following: dural, ganglionic, V3 branches, branches extending through the foramen ovale, branches directly to the greater petrosal and lesser petrosal nerves, branches to the floor of the hiatus of the greater and lesser petrosal nerves, branch to the arcuate eminence, and superior tympanic artery. No statistically significant differences were noted between male and female specimens, but right-sided petrosal arteries were in general, larger in diameter than left sides.

CONCLUSIONS

A thorough anatomical knowledge of the petrosal artery and to its relationship to the facial nerve and other neurovascular structures is necessary to facilitate effective endovascular treatment and to preclude facial nerve complications.

Variations in the branching pattern of tibial nerve in foot: a review of literature and relevant clinical anatomy

Considerable variations have been reported regarding the branching pattern of tibial nerve (TN) close to its termination in foot. In order to comprehend the clinical anatomy of heel pain awareness of all the possible variations in relation to terminal branching pattern of TN (close to the tarsal tunnel) is essential. The present study was conducted to undertake a comprehensive review of the variations in tibial nerve branches in foot with particular emphasis on the implications for sensory distribution of these branches. Articles were searched in major online indexed databases using relevant key words. The pattern of termination of TN was noted as either trifurcation or bifurcation. Bifurcation pattern was more commonly observed and is associated with the medial calcaneal nerve (MCN) either arising high or low relative to the tarsal tunnel. The most commonly noted type of bifurcation was proximal to malleolar-calcaneal axis but within the tarsal tunnel. Across all five types of bifurcation reported in literature the termination point of TN ranged from 3 cm proximal to 3 cm distal to malleolar-calcaneal axis and therefore the area beyond this region can be considered as safe zone for performing invasive procedures. MCN showed considerable variations in its origin both in trifurcation and bifurcation pattern pertaining to number of branches (one/two/three) at the point of origin. The origin of inferior calcaneal nerve (ICN) was observed to be relatively less variable as it mostly arose as a branch of lateral plantar nerve (LPN) and sometimes as a direct branch from TN before termination. The frequent variation of MCN in the tarsal tunnel should be kept in mind while undertaking decompression measures in medial ankle region.

Bihemispheric posterior inferior cerebellar artery in a cadaver with Chiari I malformation

Typically, patients with Chiari I malformations (CM I) do not have other intracranial anatomical variations, especially vascular derailments. Here, we report the findings of a cadaveric specimen found to have CM I and cerebellar tonsils supplied by a single posterior inferior cerebellar artery (PICA) i.e., a bihemispheric PICA. An adult male cadaver was found to have CM I. It was also noted that the left PICA descended inferiorly to the level of C1 and that there was absence of the right PICA. The territory of the right PICA was supplied by the left PICA. The tonsillar component of the left PICA gave rise to a branch that crossed to the right inferior cerebellum and herniated cerebellar tonsil. A bihemispheric PICA is very rare. To our knowledge, this is the first report of this vascular variation in combination with CM I. Such a variation should be kept in mind, especially during posterior fossa decompression for symptomatic CM I as unilateral PICA injury could have catastrophic results.

The first histological observation of a C1 posterior arch defect

Deficiencies in the posterior arch of C1 have been well-studied with incidences ranging from 5.65% to 3% and five different classifications. Unfortunately, there is a paucity of information describing the detailed anatomy, muscle attachments, and histology of cases with a C1 posterior arch deficiency. We found a case of an isolated unilateral posterior arch defect in the 83-years-old male cadaver. Histology revealed that the posterior arch defect was filled with collagen fibers and fibrocartilaginous tissue without muscle or bony tissues. This is the first report detailing the histological findings of a posterior arch defect of C1.

Connection between V2 and V3 parts of the trigeminal nerve at the internal cranial base

Anatomical variations can occasionally result in unexpected findings on physical examination. Here, we report two cases of seemingly unique connections between V2 and V3 parts of the trigeminal nerve. In these two cadaveric specimens, at the foramen ovale, small neural connections, confirmed with histology, were identified joining V2 to specifically, the motor root of V3. The findings of these two cadaveric specimens and the potential clinical ramifications are discussed.

ATHEROMATOSIS OF THE BRAIN-SUPPLYING ARTERIES: CIRCLE OF WILLIS, BASILAR, VERTEBRAL AND THEIR BRANCHES

PURPOSE

Atherosclerotic plaques in the brain-supplying arteries are slowly-developing alterations of vascular structures that can lead to neurological impairment due to stenosis and insufficient oxygenation of eloquent brain areas. The aim of this study is to provide detailed demographic information related to the incidence of atherosclerotic plaques in the cerebral arteries.

MATERIAL AND METHODS

Forty-eight circles of Willis (21 men, 21 women, mean age: 70.26, six samples unknown) were macroscopically analyzed for length, diameter, and presence of atherosclerotic plaques. Statistical analysis was used to identify potential differences in the locations and frequencies of atherosclerotic plaques in relation to age and sex.

RESULTS

The study sample revealed 261 atherosclerotic plaques. The key findings were significant correlations between plaque development and age and between plaque location and age; however, there was no significant sex difference.

CONCLUSION

The upper and lower branches of the middle cerebral artery (MCA) were novel locations predisposing to plaque development. A cut-off value at 60 years revealed a significant difference in plaque development and distribution. There were no significant sex differences in the occurrence of atherosclerotic plaques.

New Insights Into the Development of the Anterior Abdominal Wall

Purpose

Among the few studies that have examined the development of the anterior abdominal wall, several are based on incomplete “series”, substituted in many cases by non-human specimens.

Material and Methods

In total, 19 human embryos corresponding to Carnegie stages 15–23, 36 fetuses with estimated gestational ages ranging from 9 weeks to term, and eight neonates were included in this study. All specimens belong to the collection of the Department of Anatomy and Embryology at the Complutense University of Madrid.

Results

The muscles of the anterior abdominal wall appear in the dorsal region at stages 15 and 16 (33–37 days). At stages 17 and 18 (41–44 days), this muscular mass grows ventrally and splits into two sheets: the external abdominal oblique muscle and the common mass of the internal abdominal oblique, and the transversus abdominis muscles, all of which end ventrally in the primitive condensation of the rectus abdominis. In embryos at stages 19 and 20 (48 days), the anterior abdominal wall continues to show an umbilical hernia in the amniotic cavity. However, a narrow neck is apparent for the first time and there is a wider anterior abdominal wall below the hernia made up of dense mesenchyme tissue without layers and showing the primordia of the umbilical canal. In embryos at stages 21, 22, and 23 (51–57 days), the abdominal muscles and aponeuroses cross the midline (linea alba) covering the rectus abdominis and pyramidalis muscles while the umbilical hernia has shrunk. In fetuses during the 9th and 10th weeks, the umbilical hernia becomes encircled by the rectus abdominis muscle, its aponeurosis, and the three layers of lateral abdominal muscles, which are more developed and covered by Camper's and Scarpa's fasciae. The inguinal canal has a course and relationships like those described in adults, with Hesselbach's ligament.

A new type of the coracobrachialis muscle

The coracobrachialis muscle belongs to the anterior group of the brachial region. Its main functions are flexion and adduction at the glenohumeral joint. It is highly morphologically variable, especially in the number of bellies, place of origin or insertion, and its relationship to the musculocutaneous nerve. Accessory structures associated with the coracobrachialis muscle include the coracobrachialis brevis or coracobrachialis longus muscle. The present case describes a three-headed coracobrachialis muscle with two such additional structures. One of these has a tendinous origin connected to the periosteum and located on the surgical neck of the humerus. Its insertion is fused with the third head of the coracobrachialis muscle. The other has a proximal attachment fused with the capsule of the shoulder joint, and its distal attachment is fused with the third head of the coracobrachialis muscle in place of its connection with the short head of the biceps brachii. This could result in better stabilization of the glenohumeral joint; on the other hand, it could limit operational access during treatment of subscapularis tears.

Case report of the double headed extensor hallucis longus

BACKGROUND

We present a case report of double-headed extensor hallucis longus (EHL) with potential clinical significance.

MATERIALS AND METHODS

Cadaveric dissection of the right lower limb of a 70-year-old female at death was performed for research and teaching purposes at the Department of Anatomical Dissection and Donation, Medical University of Lodz. The limb was dissected using standard techniques according to a strictly specified protocol. Each head and tendon of the muscle was photographed and subjected to further measurements.

RESULTS

During dissection, an unusual type of EHL muscle was observed. It consisted of two muscle bellies, a main tendon and an accessory tendon. Both muscle bellies were located on anterior surface of the fibula and the interosseous membrane. The main tendon insertion was located on the dorsal aspect of the base of the distal phalanx of the big toe, while the accessory tendon insertion was located medially.

CONCLUSIONS

The EHL muscle is highly morphologically variable at both the point of origin and the insertion. Knowledge of its variationsis connected to several pathologies such as foot drop, tendonitis, tendon rupture, and anterior compartment syndrome.

Are the nerves supplying the anterior sacroiliac joint nociceptive?

BACKGROUND

Sacroiliac joint (SIJ) pain is often difficult to diagnose. Moreover, while its anatomical characteristics have been well studied, its innervation and the contributions of particular nerves remain controversial, especially in relation to posterior joint innervation. To our knowledge, previous studies have not investigated the presence of nociceptive fibres in the nerves innervating the anterior SIJ.

MATERIALS AND METHODS

Eight adult cadaveric sides underwent dissection of the anterior SIJ. Adjacent anterior rami were examined for branches to the anterior SIJ. Any branches contributing to the anterior SIJ were measured and then resected. These samples were fixed in formalin and substance P was identified immunohistologically.

RESULTS

On all sides, 1-2 small branches (mean diameter of 0.33 mm) arose from the posterior aspect of the L4 anterior ramus (12.5%), the L5 anterior ramus (62.5%), or simultaneously from both the L4 and L5 anterior rami (25%). These branches had a mean length of 13.5 mm. All histological samples contained nerve tissue. All samples of nerve fibres traveling to the anterior SIJ were positive for diffuse substance P reactivity. There were no histological differences between sides or sex. Each of the branches identified as travelling to the SIJ exhibited similar positivity for substance P.

CONCLUSIONS

This cadaveric study demonstrates that the anterior SIJ nerve fibres carry pain fibres. This new knowledge has application to patients with SIJ syndrome and to its various treatments including interventional approaches to SIJ pain.

Previously unreported variant of the rectus femoris muscle

Although uncommon, variant muscular variations can occur related to the quadriceps femoris. Such variations might be encountered in the clinical setting so these should be documented. Here, we report three additional heads related to the rectus femoris muscle identified during routine dissection of the right thigh. To our knowledge, such a variation has not been previously reported.

Accessory anterior ethmoidal nerve and artery: a cadaveric case report

The anterior ethmoidal artery (AEA) is an important surgical landmark for procedures involving the anterior cranial fossa. Many variations in the location and branching pattern of the AEA have been reported throughout the literature. These anatomical variations are important for surgeons to be familiar with as injury to the AEA can lead to massive haemorrhage, orbital haematomas, and cerebrospinal fluid rhinorrhoea. Anatomical landmarks such as the ethmoidal foramen can be used to identify the location of the AEA; however, it is also important to consider that the foramen may have variable presentations. If there is ever difficulty with identification of the AEA, surgeons should pursue a high-resolution computed tomography to minimise the risk of surgical complications. In this report, we present a rare case of a variant accessory anterior ethmoidal artery and nerve, and variations in the ethmoidal foramen found during cadaveric dissection.

Anatomical description of the perforating cutaneous nerve

BACKGROUND

The perforating cutaneous nerve/perforating nerve of the sacrotuberous ligament is rarely observed. It usually arises from the posterior division of the sacral plexus or the pudendal nerve and perforates the sacrotuberous ligament. The anatomy of this nerve and its variants is poorly described in the literature, but there are data indicating its role in pudendal neuralgia.

MATERIALS AND METHODS

Herein, we present an anatomical study of six formalin-fixed cadavers with descriptions of the topography of spinal nerves S2-S4, the pudendal bundle, the perforating cutaneous nerve and the sacrotuberous ligament.

RESULTS

We found three perforating cutaneous nerves and described each of them in detail, with measurements of length and width, and point of perforation of the sacrotuberous ligament.

CONCLUSIONS

We distinguished three types of perforating cutaneous nerve on the basis of our findings and previous publications; two of the three types were observed in our study.

Unusual sensory innervation of the dorsal hand and why we should bear this variation in mind

Detailed knowledge of the anatomy and different variations of the superficial branch of the radial nerve could be of great importance not only to anatomists but also to clinicians. A predominant radial nerve supply to the dorsum of the hand is rare. Herein, we present an unusual case of unilateral sensory innervation of the dorsal hand found during routine anatomical dissection of a 72-year-old at death male Caucasian cadaver. We also present a brief discussion of the reported variation and emphasize its potential clinical implications.

Ascending palatine branch from the lingual artery with multiple other variations of the external carotid artery

The external carotid artery (ECA) is the major blood supply for structures in the head and neck. Typically, it has 8 separate branches; but there are many anatomical variations, making it difficult to predict surgical outcomes and complications without 3-dimensional imaging. This case study focuses on a cadaver with multiple anatomical variations in the ECA, i.e., lingual, facial, occipital, ascending pharyngeal, and posterior auricular arteries, found during routine dissection of the right cadaveric neck. We also discuss the incidences of several other anatomical variations of the ECA branches and their surgical implications and potential complications.

The ulnar head of the pronator teres muscle originating from the third head of the biceps brachii: a very rare case

The biceps brachii is located in the anterior compartment of the arm, which can show numerous morphological variations. During anatomical dissection, an interesting additional muscle was found: the third head of the biceps brachii originated from the short head of the same muscle. The 97.77 mm long muscle belly was directed medially over the arm and then passed into the common tendon (15.97 mm), which thereafter split into aponeurosis and tendon. The 26.33 mm aponeurosis passed and joined the fascia of the forearm. The tendon of the third head of the biceps brachii then gave rise to the ulnar head of the pronator teres muscle. Such an accessory structure could cause neurovascular compression involving the brachial artery and median nerve. Knowledge of the morphological variability of this region is essential not only for anatomists but also for clinicians.

A previously unreported variant of the auriculotemporal nerve

Venous fenestrations are rare and when present often are not pierced by regional nerves. Herein, we report an unusual case of a fenestrated superficial temporal vein (STV). Anterior to the external ear, where the STV and superficial temporal artery normally travel with the auriculotemporal nerve (ATN), the nerve was found to pierce the STV. The fenestration within the STV was approximately 0.35mm in diameter, and there was no sign of compression of the ATN as it traversed this vessel. Following the site of penetration of the STV by the ATN, the nerve had a normal course into the skin and surrounding fascia. To our knowledge, this is the first report of a fenestrated STV being pierced by the ATN. Such an anatomical variation might be considered by clinicians who treat patients with pathology of this region.

Variant innervation of the mylohyoid muscle by the lingual nerve

The nerve to mylohyoid muscle supplies the mylohyoid and the anterior belly of the digastric muscles, with terminal sensory branches that might innervate the submental skin and mandibular teeth. The nerve to mylohyoid muscle typically originates from the posterior surface of the inferior alveolar nerve right before entering the mandibular foramen. In rare cases, the nerve to mylohyoid muscle arises from the lingual nerve. The variations of the nerve to mylohyoid muscle might have led to failure of an inferior alveolar nerve blockade. During the routine dissection of a cadaveric head, a rare case was identified where the nerve to mylohyoid muscle had origins from both the inferior alveolar and lingual nerves. This case is reviewed and salient literature reviewed.

The posterior cranial fossa's dura mater innervation and its clinical implication in headache: a comprehensive review

The pathophysiology of migraines and headaches has been a point of interest in research as they affect a large subset of the population, and the exact mechanism is still unclear. There is evidence implicating the dura mater and its innervation as contributing factors, especially at the posterior cranial fossa. Many modes of innervation have been identified, including the dorsal root ganglion, superior cervical ganglion, vagus nerve, trigeminal nerve, hypoglossal nerve, and glossopharyngeal nerve. While the exact method of innervation is still under investigation, there is strong evidence suggesting that different types of headaches (migraine vs. occipital vs. cervicogenic) are due to specific nerves and inflammatory mediators that contribute to the dura mater in some way. By understanding how these innervation patterns manifest clinically, the course of treatment can be tailored based on the physiological aetiology. Here, we present a comprehensive literature review of the current research regarding the innervation of the dura mater of the posterior cranial fossa and its clinical implications.

Anatomical variation of co-existing bilaminar tensor of the vastus intermedius muscle and new type of sixth head of the quadriceps femoris

BACKGROUND

We present a case report of quadriceps femoris (QF) with co-existing bilaminar tensor of the vastus intermedius (TVI) muscle and new type of sixth head.

MATERIALS AND METHODS

Cadaveric dissection of left thigh of a 72-year-old man was performed for research and teaching purposes at the Department of Anatomical Dissection and Donation, Medical University of Lodz. The left lower limb was dissected using standard techniques according to a strictly specified protocol. Each head of the muscle was photographed and subjected to further measurement.

RESULTS

During dissection, an unusual type of TVI muscle was observed. It consisted of two surfaces, superficial and deep. In addition, sixth head of QF muscle grew out from the vastus medialis muscle.

CONCLUSIONS

The knowledge of the existence and possible variations of additional heads of QF muscle is necessary during diagnostic process of muscle strains. Moreover, according to course of tendons that heads may take part in patella stabilisation.

Simultaneous duplication of the tendon of plantaris with multiple tendinous connections into the crural fascia

The plantaris muscle (PM) typically begins with a short, fusiform muscle belly and continues as a slim tendon traversing distally between the gastrocnemius and soleus to attach into the calcaneus directly or Achilles tendon. Conventionally, it has been of most interest as a donor for surgeons plantaris tendon (PT) grafting and recent studies have implicated the PT in the development of Achilles tendinopathy. During routine cadaveric dissection, one such anatomical variation was identified in a cadaver with two distal tendons of the PM and also multiple tendon connections into the crural fascia. While similar variants have been reported before in isolation, to our knowledge, this has been rarely reported illustrating the coexistence of a duplicated PT with simultaneous fascial connections into the crural fascia. The clinical implications of such a finding are discussed.

A computed tomography comprehensive evaluation of the ostium of the sphenoid sinus and its clinical significance

BACKGROUND

The purpose of this research was to evaluate the size of the sphenoid sinuses' ostia, the distance between them and the distance between the medial margin of the ostia and the median line in the Polish adult population.

MATERIALS AND METHODS

The analysis was undertaken as a retrospective study of 296 computed tomography (CT) scans of patients (147 females, 149 males) with no comorbidities in their sphenoid sinuses. The paranasal sinuses were investigated by using Spiral CT Scanner (Siemens Somatom Sensation 16), in the option Siemens CARE Dose 4D, without administering any contrast medium. Having obtained transverse planes, multiplans reconstruction tool was used in order to glean sagittal and frontal planes.

RESULTS

The average size of both sphenoid sinuses ostia was 0.31 cm for both genders (for females ranging from 0.1 to 0.5 cm and from 0.1 to 0.6 cm for males). The mean distance between both sphenoid sinuses ostia was 0.6 cm for both genders (the range for females was 0.1-1.4 cm, whereas 0.1-1.8 cm for males). The average distance between the medial margin of the ostium and the median line was 0.32 cm for both genders (0.31 cm for females in the range of 0-0.9 cm and 0.32 cm for males in the range of 0-1 cm).

CONCLUSIONS

Intraoperative identification of the sphenoid sinus ostia might prove difficult and their inadequate excision could lead to potential iatrogenic complications, hence detailed anatomical descriptions are still warranted in specific populations in order to perform safe and effective procedures.

"False" foramina and fissures of the skull: a narrative review with clinical implications

"False" foramina and fissures of the skull are described as openings formed between the adjacent edges of two or more bones and not conduits directly through a single bone. Trauma and metabolic disorders appear to affect these foramina and fissures differently when compared to the "true" foramina and fissures. Therefore, the aim of this paper is to provide a narrative review of the current literature about "false" foramina and fissures of the skull and skull base with a focus on their clinical significance.

Previously undescribed variant muscle connecting longissimus and semispinalis capitis muscles

Thelongissimus capitis and the semispinalis capitis both function to bilaterally extend and unilaterally rotate the head. Typically, these muscles are distinct with origins and insertions at independent locations along the vertebral column. During a routine cadaveric dissection, an unusual muscle strip was identified between the longissimus capitis andsemispinalis capitismuscles on the left, posterior neck. This anatomical variation may have developed due to an incomplete or abnormal columnar segregation during gestation. The presence of this muscle strip contributes to previous case reports that have identified abnormal musculature between and along the longissimus and semispinalis muscles. Awareness of this muscular variant should be kept in mind by clinicians and surgeons who treat/operate this area of the body.

Dual innervation of the mylohyoid muscle by the trigeminal and hypoglossal nerves: A case report

During the routine dissection of a cadaveric specimen, the left mylohyoid muscle was found to be innervated by both the trigeminal and hypoglossal nerves. This variation was found unilaterally. To our knowledge this dual innervation of the mylohyoid muscle is an extremely rare variation. The possibility of these variants may lead to clinical consequences such as anesthesia failure and iatrogenic injury during surgical procedures in this region. We discuss this anatomical variation and possible developmental etiologies.

The jugular nerve: A review of this enigmatic structure

The jugular nerve (JN) is described as joining the superior cervical ganglion to the vagus nerve. It has been studied extensively in many different animal species; however, there is very limited literature about humans. This review delves into various descriptions of this nerve's anatomy and animal studies aimed at deciphering its function. The goal is to shed more light on this understudied structure in humans.

Chiari I malformation with craniosynostosis and persistent falcine sinus draining into the straight sinus

Owing to the interconnected nature of the brain, anatomical variations in one area often coincide with, or are caused by, abnormalities in another. During dissection of a specimen with both Chiari I malformation and craniosynostosis, a persistent falcine sinus was observed to drain into the straight sinus. Such a variant should be noted by physicians as it could alter treatment plans and require more detailed imaging procedures prior to surgical correction. Herein, we report the case and discuss the possible embryological origins and clinical significance of the variant.

Dual innervation of the submandibular gland by nerve to mylohyoid and chorda tympani

The chorda tympani typically utilises the lingual nerve and submandibular ganglion to transmit parasympathetic fibres to the submandibular gland. During a routine anatomy dissection, the submandibular gland was found to be innervated by both the lingual nerve and the nerve to mylohyoid. The clinical implications of this variant dual innervation to the submandibular gland is not clear due to its rarity: however, recognising such a variation should be borne in mind during surgical intervention near the nerve to mylohyoid.

Postfixed lumbosacral plexus with split L5 ventral ramus and furcal nerve arising from L5

Variations of the peripheral nerve plexuses are important to those clinicians who diagnose and treat patients with pathology of their parts. During routine dissection, a postfixed lumbosacral plexus with a furcal nerve arising from L5, not L4, was discovered. In addition, the case was found to have a split L5 ventral ramus. Such a variation might become clinically significant during clinical presentations of radiculopathy. With a better understanding of the fucal nerve variation presented here, along with previously documented variations, the diagnostic and treatment procedures for atypical radiculopathy can be refined, reducing the rates of nerve injury and failed back surgery.

"Popliteofascial muscle" or rare variant of the tensor fasciae suralis?

Anatomical variations are routinely encountered during dissections of muscles and in clinical practice, so anatomists and clinicians need to be aware of them. One such muscle is the tensor fascia suralis, a very rare muscle located in the popliteal fossa. It can originate from any of the hamstring muscles and it inserts into the fascia of the leg. This report presents a case of a variant muscle located very deep to the biceps femoris; it originated from the posterior surface of the femur and inserted into the fascia of the leg. It is unclear whether this is a rare variant of the tensor fascia suralis or a completely new muscle.

Extensive pneumatisation of the sphenoid bone - anatomical investigation of the recesses of the sphenoid sinuses and their clinical importance

BACKGROUND

There is a great variance between the extent of pneumatisation of the sphenoid sinuses that can reach beyond the body of the sphenoid bone. The purpose of this study was to find the frequency prevalence of the recesses of the sphenoid sinuses in Polish adult population.

MATERIALS AND METHODS

296 computed tomography (CT) scans of patients who did not present any pathology in the sphenoid sinuses were evaluated in this retrospective analysis. Spiral CT scanner - Siemens Somatom Sensation 16 - was used to glean the medical images. Standard procedure applied in the option Siemens CARE Dose 4D. No contrast medium was administered.

RESULTS

In the majority of the patients - 93.92%, the pneumatisation of the sphenoid sinuses expanded beyond the body of the sphenoid bone, hence there were recesses of the sinuses present. The most common variant was the prevalence of two recesses - 12.84% of the cases. The frequency prevalence of all the 17 recesses was only 0.34%. Amongst the uneven recesses present, the sphenoidal rostrum's recess (61.15% of the patients) and the inferior clinoid recess (56.42%) were the most common. Amongst the even recesses present, the lateral recess was prevalent in the majority (65.88%), whereas the posterior clinoid process' recess was the least common (9.8%).

CONCLUSIONS

Presence of the recesses might facilitate access to the cranial fossae, hence comprehensive evaluation of the sphenoid sinuses is of immense importance in order to avoid unnecessary drills through the hard bone, that could potentially damage the nearby neurovascular structures.

Unusual formation of the musculocutaneous and median nerves: a case report refined by intraneural dissection and literature review

This report presents a detailed anatomical investigation of an upper limb specimen showing an atypical formation of the musculocutaneous (MCN) and median (MN) nerves. The study was refined by intraneural dissection, which supplements earlier descriptions of similar anatomical variations and allows for revision of the accepted classification. The case described in this report was an incidental finding during routine dissection of a fixed isolated upper limb. Intraneural dissection revealed partial fusion between the MCN and aberrant bundles of the MN. Those aberrant bundles joined the main steam of the MN at the level at which the MCN branched off as an independent nerve. The procedure allowed the aberrant fibers of the MN to be differentiated from the MCN. The presence of separate bundles in a territory corresponding to the MCN was confirmed, although those bundles and the aberrant MN bundles were covered by a common epineurium. The aberrant MN bundles running within the MCN did not contribute to innervation of the forearm muscles. They rejoined the main nerve trunk in the arm. A comprehensive understanding of the diverse anatomical variations of the upper limb nerves could be crucial for the safety and success of surgical procedures, especially procedures for reconstructing the brachial plexus or its branches.

Potential compression of the musculocutaneous, median and ulnar nerves by a very rare variant of the coracobrachialis longus muscle

The coracobrachialis longus muscle (CBL) is an extremely rare variant of the coracobrachialis muscle (CRM). The CBL originates from the apex of the coracoid process together with the short head of the biceps brachii and inserts on the olecranon of the ulna. The CBL consists of three parts: a superior part (classical CRM - length 137.88 mm), a middle fibrous layer (23.41 mm), and an inferior part (185.37 mm). A rare relationship between the CBL and median, musculocutaneous and ulnar nerves was observed with potential compression at these three parts. In addition, this case report describes a connection between CBL and the medial head of the triceps brachii, as well as a third head of the biceps brachii, which originate from the fibrous layer. This case report highlights the relationships between the CBL and the median, ulnar and musculocutaneous nerves.

The Internal Cerebral Vein: New Classification of Branching Patterns Based on CTA

BACKGROUND AND PURPOSE

The internal cerebral vein begins at the foramen of Monro by the union of the thalamostriate and the anterior septal veins. The lateral direct vein is its other major tributary. Numerous researchers have reported differences in internal cerebral vein branching patterns but did not classify them. Hence, the objectives of this study were to evaluate the anatomy of the internal cerebral vein and its primary tributaries and classify them depending on their course patterns using CTA.

MATERIALS AND METHODS

Head CTAs of 250 patients were evaluated in this study, in which we identified the number and termination of the anterior septal vein and the lateral direct vein. The course of the lateral direct vein and its influence on the number of thalamostriate veins and their diameters and courses were assessed. The anterior septal vein-internal cerebral vein junctions and their locations in relation to the foramen of Monro also were evaluated.

RESULTS

We classified internal cerebral vein branching patterns into 4 types depending on the presence of an extra vessel draining the striatum. Most commonly, the internal cerebral vein continued further as 1 thalamostriate vein (77%). The lateral direct veins were identified in 22% of the hemispheres, and usually they terminated at the middle third of the internal cerebral vein (65.45%). The most common location of the anterior septal vein-internal cerebral vein junction was anterior (57.20%), with the anterior septal vein terminating at the venous angle.

CONCLUSIONS

Detailed knowledge of the anatomy of the deep cerebral veins is of great importance in neuroradiology and neurosurgery because iatrogenic injury to the veins may result in basal nuclei infarcts. A classification of internal cerebral vein branching patterns may aid clinicians in planning approaches to the third and lateral ventricles.

The Foot-Reading Cult of Japan

Ho-no-Hana-Sanpogyo was a Japanese new religious movement referred to as the "foot-reading cult" in the media. Its founder, Fukunaga Hogen, claimed to have divine authority and the ability to diagnose physical illness by studying the soles of an individual's feet. The purpose of this paper is to provide an overview of the history of Ho-no-Hana-Sanpogyo and Fukunaga's practice of foot reading.

Three decades of managing Tomato spotted wilt virus in peanut in southeastern United States

Southeastern states namely Georgia, Florida, and Alabama produce two-thirds of the peanuts in the United States. Thrips-transmitted Tomato spotted wilt virus (TSWV), which causes spotted wilt disease, has been a major impediment to peanut production for the past three decades. The cultivars grown in the 1980s were extremely susceptible to TSWV. Early yield losses extended to tens of millions of dollars each year (up to 100% loss in many fields). This situation led to the creation of an interdisciplinary team known as "SWAT: Spotted Wilt Action Team". Initial efforts focused on risk mitigation using a combination of chemical and cultural management practices along with a strong investment in breeding programs. Beginning in the mid 1990s, cultivars with field resistance were developed and integrated with cultural and chemical management options. A Risk Mitigation Index (Peanut Rx) was made available to growers to assess risks, and provide options for mitigating risks such as planting field resistant cultivars with in-furrow insecticides, planting after peak thrips incidence, planting in twin rows, and increasing seeding rates. These efforts helped curtail losses due to spotted wilt. The Peanut Rx continues to be refined every year based on new research findings. Breeding efforts, predominantly in Georgia and Florida, continue to develop cultivars with incremental field resistance. The present-day cultivars (third-generation TSWV-resistant cultivars released after 2010) possess substantially greater field resistance than second-generation (cultivars released from 2000 to 2010) and first-generation (cultivars released from 1994 to 2000) TSWV resistant cultivars. Despite increased field resistance, these cultivars are not immune to TSWV and succumb under high thrips and TSWV pressure. Therefore, field resistant cultivars cannot serve as a 'stand-alone' option and have to be integrated with other management options. The mechanism of resistance is also unknown in field resistant cultivars. Recent research in our laboratory evaluated field resistant cultivars against thrips and TSWV. Results revealed that some resistant cultivars suppressed thrips feeding and development, and they accumulated fewer viral copies than susceptible cultivars. Transcriptomes developed with the aid of Next Generation Sequencing revealed differential gene expression patterns following TSWV infection in susceptible than field resistant cultivars. Results revealed that the upregulation of transcripts pertaining to constitutive and induced plant defense proteins in TSWV resistant cultivars was more robust over susceptible cultivars. On the flipside, the long-term effects of using such resistant cultivars on TSWV were assessed by virus population genetics studies. Initial results suggest lack of positive selection pressure on TSWV, and that the sustainable use of resistant cultivars is not threatened. Follow up research is being conducted. Improvements in TSWV management have enhanced sustainability and contributed to increased yields from <2800kg/ha before 1995 to ∼5000kg/ha in 2015.

Ectopic arachnoid granulation involving a rare intracranial venous sinus variant

Arachnoid granulations are hypertrophied arachnoid villi, which extend from the subarachnoid space into the venous system and aid in the passive filtration and reabsorption of cerebrospinal fluid. These macroscopic structures have been described in various locations, with the transverse and sigmoid sinuses seen as normal variants on imaging. Here we present the occurrence of an enlarged arachnoid granulation at the foramen rotundum where a variant intracranial venous sinus was identified during routine dissection. Variations, such as the one described herein, should be recognised by those who operate or interpret images of the skull base.

The triangles of Grynfeltt and Petit and the lumbar tunnel: an anatomo-radiologic study

PURPOSE

Lumbar hernias are protrusions of intra-abdominal contents classically through the superior (Grynfeltt) and inferior (Petit) lumbar triangles. The anatomy of the triangles is variable and quantitative data are few. No radiological data on the anatomy of the triangles are available.

METHODS

Fifty computed tomography angiography of the upper abdomen (M25, F25, mean age 72.5-year-old) were analyzed. The dimensions and the contents of the lumbar triangles were analyzed. The characteristics of the space between the two triangles were also documented.

RESULTS

The superior lumbar triangle showed a mean surface area of 5.10 ± 2.6 cm². In the area of the triangle, the 12th intercostal pedicle and the 1st lumbar branches of the iliolumbar vessels were found in 42 and 46 %, respectively. The inferior lumbar triangle had a mean surface of area 18.7 ± 8.4 cm². In this area, the 2nd, 3rd, and 4th lumbar branches were found in 9, 67, and 8 %, respectively. On oblique coronal images, a direct tunnel between the superior and the inferior lumbar triangles was found, showing an oblique course, with a postero-anterior direction (mean length 36.5 ± 5.8 mm, mean caliber 7.4 ± 3.1 mm).

CONCLUSIONS

Among the anatomical factors of weakening of the abdominal wall, the course of branches of the lumbar vessels was documented not only in the superior but also in the inferior lumbar triangle. A real musculoaponeurotic tunnel between the superior and the inferior lumbar triangles located in the oblique coronal plane was found, that could play a role in the development of incarceration or strangulation of lumbar hernias.