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.

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.

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.

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.

An unusual variant of the atlantomastoid muscle.

Knowledge of anatomical variations can be of use to clinicians and surgeons when, for example, viewing images of a patient or performing operations. Such knowledge can minimise the risk of iatrogenic complications. Herein, we present a case of a variant atlantomastoid muscle. The muscle was identified on the left side in an adult cadaver. The muscle's measurements and anatomical relationships are presented as well as a review of salient literature. We hope that increased knowledge of anatomical variants in the suboccipital region can improve patient care.

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.

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.

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.

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-year-old male cadaver. Histology revealed that the posterior arch defect was filled with collagen fibres 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.

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.

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 stabilisation of the glenohumeral joint; on the other hand, it could limit operational access during treatment of subscapularis tears.

Duplication of the foramen rotundum: A rare case report.

Variations at the skull base can result in misinterpretation of radiological imaging and occasionally, iatrogenic injury. Here, we describe, to our knowledge, the second reported case of a duplicated foramen rotundum. The morphometrics of this finding are documented and the anatomy and potential clinical consequences of such an anatomical variation discussed. Such a finding is of archival value. Additionally, foramen rotundum duplication such as found in our case might also lead to complications while using, for example, transsphenoid approaches to the middle cranial fossa as well as various transfacial treatments for trigeminal neuralgia which rely on observing the foramina around the foramen ovale on fluoroscopy for correct positioning of needles and catheters.

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.

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.

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.

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.

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 TN 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 points 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 was observed to be relativelyless variable as it mostly arose as a branch of lateral plantar nerve 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.

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.