The effectiveness of three-dimensional printing in undergraduate and postgraduate anatomy education: A review of reviews.

PURPOSE: Several reviews and meta-analyses about the value of three-dimensional (3D) printing in anatomy education have been published in the last years, with variable-and sometimes confusing- outcomes. We performed a review of those reviews, in order to shed light on the results concerning the effectiveness of 3D printing in anatomy education, compared to specific traditional methods and other technologies. METHODS: The electronic databases PubMed, ERIC and Cochrane library were searched for reviews or meta-analyses with purpose to investigate the effectiveness of 3D printing in undergraduate and postgraduate anatomy education. RESULTS: Seven papers were included: four systematic reviews with meta-analysis, one narrative, one scoping and one systematic review. Overall, it has been shown that 3D printing is more effective than two-dimensional (2D) images for undergraduate health science students, but not for medical residents. Also, it seems to be more effective than 2D methods for teaching anatomy of some relatively complex structures, such as the nervous system. However, there is generally lack of evidence about the effectiveness of 3D printing in comparison with other 3D visualization methods. CONCLUSIONS: For students, the effectiveness of 3D printing in anatomy education is higher than 2D methods. There is need for studies to investigate the effectiveness of 3D printing in comparison with other 3D visualization methods, such as cadaveric dissection, prosection and virtual reality. There is also need for research to explore if 3D printing is effective as a supplementary tool in a blended anatomy learning approach.

Anatomical variations of the superior thyroid artery: A systematic review.

BACKGROUND: The superior thyroid artery (STA) is one of the main arteries that provide blood supply to the thyroid gland. It has a plethora of anatomical variations, and knowledge of its anatomy is necessary in procedures in this area. The aim of this review is to summarize and describe human studies (cadaveric and angiographic) that investigate the anatomical variations related to the STA. MATERIAL AND METHODS: A systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was performed. A literature search in PubMed, and Embase databases was carried out. Original studies that investigated the origin of the STA and reported data on the variant arterial anatomy were considered, including only cadaveric and angiographic studies. RESULTS: A total of 34 studies (4048 heminecks in total; heminecks in each study: min: 25-max: 1280) were finally included. All studies provide details about sex [men/women ratio median (IQR): 2(1-5)] but none about age and 10 (29%) about nationality. STA morphological characteristics described in the included studies are origin, length, number of branches, distance from the carotid bifurcation and the vessel's diameter. CONCLUSIONS: The STA's anatomical features are subject to a non-negligible degree of variability. Our results should improve the awareness of anatomical variations of the STA, and eventually have an impact on the interventions regarding the visceral compartment of the neck in clinical practice.

Anatomical variations of human vertebral and basilar arteries: A current review of the literature.

The vertebral artery originates from the subclavian artery and is divided into four segments (V1-V4). In its intracranial segment (V4), the two vertebral arteries join to form the basilar artery, an unpaired medium-sized artery. However, apart from this typical description, several anatomical variations may occur in the human body. Although in some cases such variations may be asymptomatic, they may be also associated with several pathological conditions, neurological complications, surgical complications, and increased risk of developing vascular diseases. Therefore, it is crucial to obtain sufficient information on the anatomy and variants of both arteries to prevent such complications and ensure the safe completion of surgical and radiological treatments. For this reason, we reviewed studies published up to January 2022 concerning the reported variations of the vertebral artery and basilar artery regarding their origin, course, length, and diameter. We believe that the thorough presentation of these variations would help surgeons worldwide during their daily clinical and surgical practice.

Anatomical variations of the pelvis during abdominal hysterectomy for benign conditions.

BACKGROUND: Anatomical variations are defined as atypical morphologic and positional presentations of anatomical entities. Pelvic anatomical variations encountered during abdominal hysterectomy can be of clinical interest, given that misidentification of certain structures can lead to iatrogenic injuries and postoperative sequelae. The aim of the present study was to detect and highlight the anatomical structures of interest and their variations to the surgeon performing abdominal hysterectomy for benign conditions. MATERIALS AND METHODS: A narrative review of the literature was performed including reports of anatomical variations encountered in cadavers, by surgeons during abdominal hysterectomy and radiologists on computed tomography angiography, searching within a 10-year span on PubMed database. Studies regarding the treatment of malignant conditions requiring lymphadenectomy and different modes of surgical approach were reviewed with regards to the aspects relevant to benign conditions. The search was extended to the reference lists of all retrieved articles. RESULTS: Ureters and the uterine arteries, due to anatomical variations, are the anatomical structures most vulnerable during abdominal hysterectomy. Specifically, the ureters can present multiplications, retroiliac positionings and ureteric diverticula, whereas, the uterine arteries can present notable variability in their origins. Such variations can be detected preoperatively or intraoperatively. CONCLUSIONS: Although rare, the presence of anatomical variations of the uterine arteries and ureters can increase the possibility of complications should they escape detection. Intraoperative misidentification could lead to improper dissection or ligation of the affected structures. Knowledge of these variations, coupled with extensive preoperative investigation and intraoperative vigilance can minimise the risk of complications.

Anatomical variations of the vascular supply of the cutaneous component of the serratus anterior myocutaneous flap: a systematic review.

Although appealing from a reconstructive standpoint, the incorporation of the overlying skin in a serratus anterior muscle flap has not yet seen widespread use, due to considerations with its blood supply. In the present study, a systematic review of the literature has been performed, evaluating studies that investigated the vascular anatomy and variations of serratus anterior myocutaneous flap. The anatomy of the cutaneous blood supply, the size of the cutaneous territory, the design of the skin paddle and the reconstructive goals were analysed. The results showed that the main blood supply originates from the intramuscular anastomoses between intercostal artery perforators and the serratus artery branch in the form of choke vessels. Complementary perfusion from true intramuscular vessel anastomoses or from direct serratus artery cutaneous perforators could contribute to the skin blood supply but only in 25% of the cases. The design of the flap is elliptical with its long axis over the harvested muscle slips and maximum width is 6-8 cm. A myocutaneous serratus anterior flap could be applied in a variety of reconstructive fields, most commonly for head and neck defects. A delay procedure would considerably enhance the perfusion of the cutaneous component and improve the overall viability of the flap.

The role of LigaSure™ and Harmonic Scalpel in the preservation of recurrent laryngeal nerve during thyroidectomy.

INTRODUCTION: Transient or permanent damage to the recurrent laryngeal nerve (RLN) during thyroidectomy is of paramount importance for patient quality of life. The aim of this study is to systematically review the literature concerning the role of the most popular energy-based vessel-sealing devices (LigaSure™ (LS) and Harmonic Scalpel (HS)) in preservation of the RLN during thyroidectomy. The safety and inferiority or superiority of LS and HS compared with conventional haemostatic techniques are highlighted. METHODS: A systematic search of the literature was performed. Clinical trials, prospective and retrospective studies that significantly compared the use of LS and HS with conventional haemostasis regarding the postoperative incidence of RLN palsy were included. FINDINGS: The search resulted in 43 studies, including 17,953 patients treated using energy-based devices or conventional haemostatic methods. Concerning the incidence of RLN palsy, 40 studies showed no significant difference between the energy-based device and conventional groups, whereas two studies demonstrated a significant superiority in performance for LS and HS compared with conventional haemostasis. Only one study exhibited significant inferiority of LS and HS compared with conventional methods. No statistical relationship was observed between energy-based devices and conventional techniques regarding permanent damage to the RLN. CONCLUSION: The performance of both LS and HS shows no inferiority compared with conventional haemostatic techniques, regarding damage to the laryngeal nerve. Further well-designed studies are needed to investigate their potential benefit in preservation of the RLN.

Lymphedema duration as a predictive factor of efficacy of complete decongestive therapy.

Lymphedema is a common condition with global impact and a multitude of complications, however, only a few professionals specialize in its management. A retrospective analysis of 105 subjects with unilateral lymphedema upper or lower limb was performed to investigate whether the duration of lymphedema constitutes an important factor associated with the efficacy of complete decongestive therapy (CDT). Subjects were classified into two groups according to the duration of lymphedema, prior to CDT: group A (≤1 year) and group B (>1 year). Both groups were treated daily according to the same CDT protocol for four weeks. The CDT efficacy was determined based on the percent reduction of excess volume (PREV) measurements. Lymphedema was significantly reduced in both groups of subjects, but significantly more in group A (p<0.001). In subjects with upper limb lymphedema, median value of PREV was 80.8% (interquartile range, 79.1-105.0%) in group A and 62.0% (interquartile range, 56.7-66.5%) in group B (p<0.001). In subjects with lower limb lymphedema PREV was 80.7% (interquartile range, 74.9-85.2%) and 64.5% (interquartile range, 56.0-68.1%) for groups A and B, respectively (p<0.001). Duration of lymphedema was found to be a strong predictive factor that may significantly impact CDT efficacy. Therapeutic effects were increased in subjects who were detected and treated earlier for lymphedema.

Vertebral artery variations revised: origin, course, branches and embryonic development.

BACKGROUND: The vertebral artery originates from the subclavian artery and is divided into four segments. The aim of this study is to investigate the anatomical variations in the course and branches of the vertebral artery. MATERIALS AND METHODS: A research was performed via PubMed database, using the terms: "variations of vertebral artery AND cadaveric study", "variations of vertebral artery AND cadavers" and "anomalies of vertebral artery AND cadavers". RESULTS: A total of 24 articles met the inclusion criteria, 13 of them referring to variations of the origin of the vertebral artery, 9 to variations of the course and 3 to variations of its branches. On a total sample of 1192 cadavers of different populations, origin of the left vertebral artery directly from the aortic arch was observed at 6.7%. In addition, among 311 cadavers, 17.4% were found with partially or fully ossified foramen of the atlas for the passage of the vertebral artery, while the bibliographic review also showed variants at the exit site of the artery from the transverse foramen of the axis. CONCLUSIONS: Despite the fact that variations of both the course and the branches of vertebral artery are in most cases asymptomatic, good knowledge of anatomy and its variants is of particular importance for the prevention of vascular complications during surgical and radiological procedures in the cervix area.

Agenesis of the coeliac trunk: a case report and review of the literature.

Vascular anatomical variations of the abdomen are very common. Awareness of these variations is of paramount importance in clinical practice mainly in achieving best results in minimal invasive or surgical vascular procedures. From surgical point of view, the preoperative knowledge of vascular anatomy and the relations to the surrounding structures and tissues aims to minimise inadvertent complications. Agenesis of the coeliac trunk is one of the rare anatomical variations of the abdominal aorta. Limited number of cases have been reported in the medical literature, most of which are based on angiographic and cadaveric studies of adult humans. In this paper, we report a case of absence of the coeliac trunk that has been detected as an incidental radiological finding in a female patient who was admitted with abdominal pain.

Anatomical study of the common iliac arteries.

BACKGROUND: The common iliac arteries (CIA) are the two terminal branches of the abdominal aorta which supply the pelvis and the lower extremities. The present study aims to examine the morphometric features of the CIA in a cadaveric sample and possible correlations between lengths. MATERIALS AND METHODS: Seventy-six formalin fixed cadavers of Greek origin were dissected in the Department of Anatomy, School of Medicine, National and Kapodistrian University of Athens. In each cadaver dissected, the abdominal aorta and the CIA were identified and their lengths were measured. Also the torso length was measured and the height of each cadaver. All the statistical analysis was done by SPSS 15.0. RESULTS: The mean length of the left CIA was 6.12 cm (SD: ± 1.791, SE: 0.205) and that of the right one was 6.03 cm (SD: ± 1.607, SE: 0.184). The lengths of the CIA differed between the sexes, but no statistically significant difference was observed. Statistically significant differences regarding the torso lengths and body heights were found between the sexes, as well as a statistically strong correlation between the lengths of the left and right CIA in the cadavers dissected. CONCLUSIONS: The knowledge of the anatomy and morphology of the CIA is ofgreat clinical significance, given that abnormal course, length or branching pattern of these vessels are not uncommon and their clinical impact may be great. Mostly interventional radiologists and vascular surgeons should be aware of this knowledge.

Case series and a systematic review concerning the level of the aortic bifurcation.

BACKGROUND: The aim of this study is to present the level of aortic bifurcation in a sample of Greek origin (case series) and to perform an up-to-date systematic review in the existing literature. MATERIALS AND METHODS: Seventy-six formalin-fixed adult cadavers were dissected and studied in order to research the level of aortic bifurcation. Additionally, PubMed and Google Scholar databases were searched for eligible articles concerning the level of aortic bifurcation for the period up to February 2020. RESULTS: The mean level of aortic bifurcation according to our case series was the lower third of the L4 vertebral body (21/76, 27.6%). The level of aortic bifurcation ranged between the lower third of the L3 vertebral body and the lower third of the L5 body. No statistically significant correlation was found between the two sexes. The systematic review of the literature revealed 31 articles which were considered eligible and a total number of 3537 specimens were retracted. According to the recorded findings the most common mean level of aortic bifurcation was the body of L4 vertebra (1495/3537 cases, 42.2%), while the range of aortic bifurcation was described to occur from upper third of L3 vertebrae to the upper third of the S1 vertebrae in the 52.8% of the cases (1866/3537). CONCLUSIONS: The mean level of AA corresponds to the body of L4 and presents a great range (form L3U to S1U). Knowledge of the mean level of aortic bifurcation and its probable ranges is of great significance for interventional radiologists and especially vascular surgeons that deal with aneurism proximal to the aortic bifurcation.

Anatomical variation of a trifid (trifurcation) lateral root origin of the median nerve.

Anatomic variations of the brachial plexus are common. Awareness of these variations is of paramount importance in clinical practice mainly in achieving best results in minimal invasive or surgical procedures. The aim of our study was to depict a case of a trifid lateral root origin of the medial nerve. This anatomical variation in the brachial plexus was encountered after dissection in upper extremities in a 90-year-old male cadaver.

Accessory muscles of the anterior thoracic wall and axilla. Cadaveric, surgical and radiological incidence and clinical significance during breast and axillary surgery.

BACKGROUND: The present study aims to summarise the accessory muscles of the anterior thoracic wall and axilla that can be encountered during breast and axillary surgery and record their incidence and clinical significance. Moreover, the laterality of the atypical muscles is highlighted and possible gender dimorphism is referred. Accessory anterior thoracic wall muscles include: Langer's axillary arch, sternalis muscle, chondrocoracoideus, chondroepitrochlearis, chondrofascialis, pectoralis minimus, pectoralis quartus and pectoralis intermedius. MATERIALS AND METHODS: The anatomical, surgical and radiological literature has been reviewed and an anatomical study on 48 Greek adult cadavers was performed. RESULTS: Literature review revealed the existence of accessory muscles of the anterior thoracic wall and axilla that have a significant incidence that can be considered high and may, therefore, have clinical significance. For the most common of these muscles, which are axillary arch (Langer's) and sternalis muscle, the cadaveric incidence is 10.30% and 7.67%, respectively. In the current cadaveric study, accessory thoracic wall muscles were identified in two cadavers; namely a bilateral sternalis muscle (incidence 2.08%) extending both to the anterior and posterior surface of the sternum and a left-sided chondrocoracoideus muscle (of Wood) (incidence 2.08%). CONCLUSIONS: Despite the fact that accessory anterior thoracic wall and axillary muscles are considered to be rare, it is evident that the incidence of at least some of them is high enough to encounter them in clinical practice. Thus, clinicians' awareness of these anatomical structures is advisable.

Body donation for research and teaching purposes: the contribution of blood donation units in the progress of anatomical science.

BACKGROUND: Cadaver's dissection has a fundamental role in teaching and understanding the anatomy. Postmortem body donation (PMBD) is an important source of cadavers and provides an opportunity to carry out research or educational activities in medicine and surgery. The objective of the current study is to determine the perspectives and attitudes toward PMBD among blood donors (BLD) and elderly people. These data are fundamental to highlight the PMBD extent and individual factors that might influence PMBD. MATERIALS AND METHODS: Six hundred and fifty questionnaires were distributed to 500 (327 male and 173 female, mean age 39.9 ± 9.6 years) blood donors (BLD) and 150 elderly people (62 males and 88 females, mean age 74 ± 9.4 years). A specially designed self-administered questionnaire covering demographic data, knowledge and attitude of the participants concerning body donation (BD) was used. RESULTS: Concerning the perception of BD among BLD and elderly people, the most common reason for BD in both study groups was the contribution in research, while the commonest reason for hesitating about BD was the lack of information, following by personal reasons. The BLD were more likely to be interested in BD for contribution in research and personal reasons. Additionally, BLD were less likely than the elderly to hesitate about BD for religious and personal reasons and more likely to hesitate about BD for not being informed. BLD who were interested in BD for contribution in research were significantly older. Elderly people who hesitated about BD for personal reasons were significantly older. In the BLD group, those who responded that blood and body donation are the same were significantly younger, while in the elderly group - significantly older. The proportion of BLD who declared that blood and body donation is the same was significantly higher in more educated people. CONCLUSIONS: A need for well-organised and informative BD programmes is evident. Orientating the public towards this practice is of high moral and medical value, since with this important promotion the altruistic act of BD will expand globally.

Littre's hernia: a systematic review of the literature.

PURPOSE: A hernia containing Meckel's diverticulum is called a Littre's Hernia. It's a rare entity and its diagnosis is often incidental during routine hernia repair surgery. The objective of this study is the evaluation of the current evidence on Littre's hernias regarding their clinical presentation and optimal treatment approach. METHODS: PubMed and Cochrane bibliographical databases were searched from the beginning of time (last search: August 1st, 2018) for studies reporting on Littre's hernias in adult population. RESULTS: Forty-five studies met our inclusion criteria and reported collectively on 53 patients (21 males and 32 females) presenting at health care units with a Littre's hernia. The most common sites of occurrence were femoral (39.6%) and inguinal (34%). The vast majority of cases (77.4%) concerned incarcerated hernias. All patients underwent surgical hernia repair accompanied by a diverticulectomy and 16.9% of them received mesh. Only 7.5% of patients experienced immediate postoperative complications. CONCLUSIONS: A Littre hernia is a rare complication of Meckel's diverticulum. It requires surgical attention and all medical professionals should be encouraged to report such cases to expand our experience and optimize the therapeutic approach.

The position of the mental foramen in dentate and edentulous mandibles: clinical and surgical relevance.

BACKGROUND: The knowledge of the exact location of the mental foramen (MF) in dentate and edentulous mandibles is clinically important when constructing complete dentures, performing anaesthetic block of the lower-anterior teeth area and intervening in the MF nearby area. In edentulous mandibles, the bone resorption after teeth loss makes the mental nerve (MN) prone to damage due to the extreme location of the MF very close to the alveolar crest (AC). Chronic compression on the MN may result in pain in the area of MN distribution (ipsilateral face and cheek area) and numbness at the lower lip. The purpose of the current study is to evaluate the exact position of the MF, calculating the distances MF-superior border of the AC and MF-inferior border of the mandible (IBM) in dentate and edentulous mandibles. MATERIALS AND METHODS: One hundred and two (36 edentulous and 66 dentate) adult dry Greek mandibles were studied. RESULTS: In 9 out of 36 edentulous mandibles (25%), the MF was found nearby the AC, while in 27 edentulous mandibles (75%), the MF was located at an average distance 6.4 mm from the AC and 12.6 mm from the IBM. In 38 out of 66 dentate mandibles (57.6%), the MF was located at an average distance 13.6 mm from the AC and 15.2 mm from the IBM. The dental status significantly affected (p = 0.001) the distances MF-AC and MF-IBM. Side symmetry was observed for both dentate and edentulous mandibles (p = 0.39 and p = 0.45). CONCLUSIONS: The MF is an important landmark and its location needs to be considered prior to dental implants placement in order to avoid the MN injury and related complications. The position of MF is altered in edentulous mandibles compared with the dentate ones. The MF is a symmetric structure in Greeks.

Tetrafurcation of the subscapular artery. Anatomical and clinical implications.

Anatomic variations of axillary artery branches are commonly encountered during radiological investigation and surgical operations. Their existence can confuse interpretation of radiological results and lead to undesired complications during surgery. In this report authors describe a rare case of a subscapular arterial trunk that gave origin to thoracodorsal, circumflex scapular, posterior humeral circumflex, and lateral thoracic artery. Such a variation might cause undesired sequelae during trauma management and a variety of common flap harvesting operations including latissimus dorsi, scapular and parascapular flaps. Furthermore it presents embryological interest as it gives insight to embryologic development of axillary area.

A study concerning morphometry of abdominal aorta branches and abdominal viscera: relations and correlation.

Research interest on abdominal aorta branches and abdominal viscera morphometry is renewed by technological evolution and development of new radiologic and clinical applications including stent grafts and chemoembolisation materials. Despite that, data on morphometry of abdominal aorta branches and abdominal viscera are lacking. To investigate this subject authors performed a morphometric study on 50 adult fresh and embalmed Caucasian cadavers and examined abdominal aorta branches', kidney and spleen morphometry. Our results on arteries' morphometry did not differ significantly from those of the literature; yet, we discovered significant differences between fresh and embalmed cadavers on viscera morphometry, spleen and kidneys. We also found previously unreported correlations between abdominal aorta branches' morphometric characteristics. Even more, we identified correlations between regional arteries and viscera morphometric characteristics, proposing a new factor determining viscera development. Finally, we performed an extensive literature review so to place our results in an anatomic, embryologic and, even more, a clinical context. We believe that our results add knowledge on abdominal aorta branches and viscera morphometry and are valuable for clinical, radiological and surgical applications including visceral arteries' aneurysms investigation and treatment, chemoembolisation procedures, stent grafts design and transplantation.

Bilateral lingual-facial trunk: anatomic and clinical implications.

Common origin of lingual and facial artery is a relatively frequent anatomic varia-tion. Instead, bilateral lingual-facial trunk has been described only sparsely in the literature. In this report authors describe and analyse a case of bilateral common lingual-facial trunk in the context of its anatomical, clinical and embryological implications. We also describe possible consequences in performance of elective and emergent surgical operations and modification in surgical techniques that should be considered. We believe that surgeons should be suspicious for this variation's existence and keep alternative solutions in their armentarium.

Idiopathic guttate hypomelanosis: an electron microscopy study.

BACKGROUND: Few published data, concerning the electron microscopy findings of idiopathic guttate hypomelanosis have been published so far. OBJECTIVES: To reveal the electron microscopic findings of idiopathic guttate hypomelanosis and their aetiopathogenetic associations. METHODS: Punch biopsy specimens from four patients with idiopathic guttate hypomelanosis, after being properly processed, were observed under the electron microscope. RESULTS: In the epidermis, melanocytes and melanosomes were normal in structure. In some areas, there was a reduced uptake of melanosomes by the keratinocytes. In the dermis, fibroblasts were structurally normal. Also, most elastic and collagen fibres were normal, but there were focal elastotic changes. CONCLUSIONS: No significant structural abnormality of the melanocytes was observed, but rather a functional defect in the transfer of melanosomes from the melanocytes to the keratinocytes.