BACKGROUND

The COVID-19 pandemic resulted in the lack of traditional cadaveric dissection among first year medical students in Anatomy courses in the University of the Philippines College of Medicine. The Learning Enhancement in Anatomy Program (LEAP) was implemented as a bridging program to enhance knowledge and understanding of gross anatomy and histology. As part of this program, a novel multi-strategy teaching method was conducted for the Integumentary and Musculoskeletal Anatomy Module.

This case study described a novel multi-strategy teaching method on Integumentary and Musculoskeletal anatomy for first year medical students which was done after the COVID-19 pandemic wherein there was a shortage of cadavers. By describing this multi-strategy teaching method, this case study aims to present a potential alternative teaching method in a situation where there is an unexpected shortage of human cadavers.

A retrospective review of documents related to this teaching method among first year medical students at the University of the Philippines College of Medicine was conducted from November 15, 2023, to January 15, 2024. The novel teaching method for the Integumentary and Musculoskeletal station was taught using five different methods: proctor demonstration, a prosected lower extremity with a self-directed manual, dissection education videos viewed on a large screen, skeletons for osteology, and individual light microscopes with a self-directed laboratory histology manual. We described the data and analyzed according to strengths and limitations, and formulated recommendations to improve the module.

The Integumentary and Musculoskeletal Module of the LEAP provided an interactive, hands-on experience in anatomy education. The five-pronged method facilitated a multifaceted approach to learning through cadaveric prosections, self-directed manuals, dissection videos, osteology exercises, and microscopic study. There was active engagement, overall positive student feedback, and increased post-test scores. However, certain limitations, such as the lack of direct cadaveric dissection, potential underutilization of histology components, and reliance on faculty guidance, highlight areas for improvement.

The Integumentary and Musculoskeletal Module of the LEAP has demonstrated significant strengths in enhancing anatomical education through a multimodal approach that fosters active learning, improves knowledge retention, and provides a structured curriculum adaptable to various resource constraints. Student feedback and test performance support the effectiveness of the module, particularly in gross anatomy. Addressing challenges in future iterations will be crucial in refining the program and expanding its applicability to different educational contexts. By building on its strengths and mitigating its weaknesses, this five-pronged method can continue to serve as a model for innovative and effective anatomy education. 

Humans ; Water ; Rivers ; Skull/anatomy & histology* ; Brain/diagnostic imaging* ; Forensic Medicine ; Forensic Anthropology

It is a basic prerequisite for the successful completion of endodontic treatment to thoroughly understand the root canal space anatomy. With the development of dental devices in dentistry, the root canal morphology of the mandibular first premolars can be presented in more detail. Before conducting root canal therapy on the mandibular first premolar with complex root canal morphology, it should be necessary to evaluate the potential difficulties and risks for making an appropriate treatment plan. The present paper reviews the research progress on the diversities of root canal morphology in mandibular first premolars in recent years, and then makes technologic recommendations based on the morphology diversities.
Humans ; Dental Pulp Cavity/diagnostic imaging* ; Bicuspid/anatomy & histology* ; Mandible ; Tooth Root/anatomy & histology* ; Root Canal Therapy

OBJECTIVE: To explore an efficient and automatic method for determining the anatomical landmarks of three-dimensional(3D) mandibular data, and to preliminarily evaluate the performance of the method. METHODS: The CT data of 40 patients with normal craniofacial morphology were collected (among them, 30 cases were used to establish the 3D mandibular average model, and 10 cases were used as test datasets to validate the performance of this method in determining the mandibular landmarks), and the 3D mandibular data were reconstructed in Mimics software. Among the 40 cases of mandibular data after the 3D reconstruction, 30 cases that were more similar to the mean value of Chinese mandibular features were selected, and the size of the mandibular data of 30 cases was normalized based on the Procrustes analysis algorithm in MATLAB software. Then, in the Geomagic Wrap software, the 3D mandibular average shape model of the above 30 mandibular data was constructed. Through symmetry processing, curvature sampling, index marking and other processing procedures, a 3D mandible structured template with 18 996 semi-landmarks and 19 indexed mandibular anatomical landmarks were constructed. The open source non-rigid registration algorithm program Meshmonk was used to match the 3D mandible template constructed above with the tested patient's 3D mandible data through non-rigid deformation, and 19 anatomical landmark positions of the patient's 3D mandible data were obtained. The accuracy of the research method was evaluated by comparing the distance error of the landmarks manually marked by stomatological experts with the landmarks marked by the method of this research. RESULTS: The method of this study was applied to the data of 10 patients with normal mandibular morphology. The average distance error of 19 landmarks was 1.42 mm, of which the minimum errors were the apex of the coracoid process [right: (1.01±0.44) mm; left: (0.56±0.14) mm] and maximum errors were the anterior edge of the lowest point of anterior ramus [right: (2.52±0.95) mm; left: (2.57±1.10) mm], the average distance error of the midline landmarks was (1.15±0.60) mm, and the average distance error of the bilateral landmarks was (1.51±0.67) mm. CONCLUSION The automatic determination method of 3D mandibular anatomical landmarks based on 3D mandibular average shape model and non-rigid registration algorithm established in this study can effectively improve the efficiency of automatic labeling of 3D mandibular data features. The automatic determination of anatomical landmarks can basically meet the needs of oral clinical applications, and the labeling effect of deformed mandible data needs to be further tested.
Humans ; Imaging, Three-Dimensional/methods* ; Mandible/diagnostic imaging* ; Software ; Algorithms ; Anatomic Landmarks/anatomy & histology*

Background: Medical education has changed as a result of the COVID-19 pandemic. There has been a shift from face to face learning to virtual classes using online learning platforms such as Canvas. These virtual and online alternative methods to medical education brought up concerns about the preparedness of medical students in studying Histology. This study addresses the student’s preference and attitude on the learning of histology using light microscopy vs virtual microscopy. Objectives: The specific objectives of the study are to determine students’ preference, attitudes, and overall satisfaction on the use of light microscopy vs virtual microscopy using a Likert scale. Methods: An enhancement program was conducted by the Department of Anatomy, UP College of Medicine from June 13 to June 17, 2022 among first year medical students. The students were exposed to prosected cadavers, models, specimens, histologic glass slides, and electronic images. During the activity, the second and third floor of Calderon Hall was divided into several stations, each with its own learning outcomes.This is a descriptive cross-sectional study. In all the learning stations, both virtual and light microscopy learning modalities were made available to the students. The student was at liberty to select virtual microscopy, light microscopy or both. In one of the stations, allocated to OS 205 (The study of the anatomy and histology of the thorax), students were randomized to one learning modality (light vs virtual microscopy) and made to identify one predetermined structure. Students answered a short questionnaire that allowed them to express their preference for the modality that was assigned. The questionnaire survey included questions on students’ preference for either light microscopy (LM) or virtual microscopy (VM), ease of use, and satisfaction. A total of five statements were included in the survey questionnaire. All questions in the survey were scored on a 5-point Likert scale (5: strongly disagree, 4: disagree, 3: neutral, 2: agree, and 1: strongly agree). A comments section was also included in the survey to explore students’ experiences of the two learning methods. Results: A total of 160 students participated in the study. Seventy-nine (79) students were randomized to the light microscopy group and 81 one students were randomized to the virtual microscopy group. There were no differences in the demographic characteristics between those randomized to virtual vs light microscopy.There were no differences in the net ratings between those randomised to virtual vs light microscopy in the following domains: 1) ease in looking for structures, 2) ability to identify the structure correctly, 3) method enhancing learning, and 4) overall satisfaction. There was a difference in the net rating between those randomized to virtual vs light microscopy in the domain on quality of the image being easily adjusted (58% vs 97.5%). Conclusion Medical students who used light microscopes demonstrated a more positive attitude towards its ability to enhance learning and showed greater satisfaction in using this method. Ease in manipulating image quality was better in the light microscopy group. However, the accuracy of identification of histological structures using either platform did not differ. Both virtual and light microscopy are effective learning methods.
Microscopy ; Education, Medical ; Histology ; Teaching

Understanding of a variety of membranous structures throughout the body,such as the fascia,the serous membrane,is of great importance to surgeons. This is especially valuable in abdominal surgery. With the rise of membrane theory in recent years,membrane anatomy has been widely recognized in the treatment of abdominal tumors,especially of gastrointestinal tumors. In clinical practice. The appropriate choice of intramembranous or extramembranous anatomy is appropriate to achieve precision surgery. Based on the current research results,this article described the application of membrane anatomy in the field of hepatobiliary surgery,pancreatic surgery,and splenic surgery,with the aim of blazed the path from modest beginnings.
Humans ; Mesentery/surgery* ; Digestive System Surgical Procedures ; Fascia/anatomy & histology*

Objective: To explore an automatic landmarking method for anatomical landmarks in the three-dimensional (3D) data of the maxillary complex and preliminarily evaluate its reproducibility and accuracy. Methods: From June 2021 to December 2022, spiral CT data of 31 patients with relatively normal craniofacial morphology were selected from those who visited the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology. The sample included 15 males and 16 females, with the age of (33.3±8.3) years. The maxillary complex was reconstructed in 3D using Mimics software, and the resulting 3D data of the maxillary complex was mesh-refined using Geomagic software. Two attending physicians and one associate chief physician manually landmarked the 31 maxillary complex datasets, determining 24 anatomical landmarks. The average values of the three expert landmarking results were used as the expert-defined landmarks. One case that conformed to the average 3D morphological characteristics of healthy individuals' craniofacial bones was selected as the template data, while the remaining 30 cases were used as target data. The open-source MeshMonk program (a non-rigid registration algorithm) was used to perform an initial alignment of the template and target data based on 4 landmarks (nasion, left and right zygomatic arch prominence, and anterior nasal spine). The template data was then deformed to the shape of the target data using a non-rigid registration algorithm, resulting in the deformed template data. Based on the unchanged index property of homonymous landmarks before and after deformation of the template data, the coordinates of each landmark in the deformed template data were automatically retrieved as the automatic landmarking coordinates of the homonymous landmarks in the target data, thus completing the automatic landmarking process. The automatic landmarking process for the 30 target data was repeated three times. The root-mean-square distance (RMSD) of the dense corresponding point pairs (approximately 25 000 pairs) between the deformed template data and the target data was calculated as the deformation error of the non-rigid registration algorithm, and the intra-class correlation coefficient (ICC) of the deformation error in the three repetitions was analyzed. The linear distances between the automatic landmarking results and the expert-defined landmarks for the 24 anatomical landmarks were calculated as the automatic landmarking errors, and the ICC values of the 3D coordinates in the three automatic landmarking repetitions were analyzed. Results: The average three-dimensional deviation (RMSD) between the deformed template data and the corresponding target data for the 30 cases was (0.70±0.09) mm, with an ICC value of 1.00 for the deformation error in the three repetitions of the non-rigid registration algorithm. The average automatic landmarking error for the 24 anatomical landmarks was (1.86±0.30) mm, with the smallest error at the anterior nasal spine (0.65±0.24) mm and the largest error at the left oribital (3.27±2.28) mm. The ICC values for the 3D coordinates in the three automatic landmarking repetitions were all 1.00. Conclusions: This study established an automatic landmarking method for three-dimensional data of the maxillary complex based on a non-rigid registration algorithm. The accuracy and repeatability of this method for landmarking normal maxillary complex 3D data were relatively good.
Male ; Female ; Humans ; Adult ; Imaging, Three-Dimensional/methods* ; Reproducibility of Results ; Algorithms ; Software ; Tomography, Spiral Computed ; Anatomic Landmarks/anatomy & histology*

Objective: To document the anatomical structure of the area anterior to the anorectum passing through the levator hiatus between the levator ani slings bilaterally. Methods: Three male hemipelvises were examined at the Laboratory of Clinical Applied Anatomy, Fujian Medical University. (1) The anatomical assessment was performed in three ways; namely, by abdominal followed by perineal dissection, by examining serial cross-sections, and by examining median sagittal sections. (2) The series was stained with hematoxylin and eosin to enable identification of nerves, vessels, and smooth and striated muscles. Results: (1) It was found that the rectourethralis muscle is closest to the deep transverse perineal muscle where the longitudinal muscle of the rectum extends into the posteroinferior area of the membranous urethra. The communicating branches of the neurovascular bundle (NVB) were identified at the posterior edge of the rectourethralis muscle on both sides. The rectum was found to be fixed to the membranous urethra through the rectourethral muscle, contributing to the anorectal angle of the anterior rectal wall. (2) Serial cross-sections from the anal to the oral side were examined. At the level of the external anal sphincter, the longitudinal muscle of the rectum was found to extend caudally and divide into two muscle bundles on the oral side of the external anal sphincter. One of these muscle bundles angled dorsally and caudally, forming the conjoined longitudinal muscle, which was found to insert into the intersphincteric space (between the internal and external anal sphincters). The other muscle bundle angled ventrally and caudally, filling the gap between the external anal sphincter and the bulbocavernosus muscle, forming the perineal body. At the level of the superficial transverse perineal muscle, this small muscle bundle headed laterally and intertwined with the longitudinal muscle in the region of the perineal body. At the level of the rectourethralis and deep transverse perineal muscle, the external urethral sphincter was found to occupy an almost completely circular space along the membranous part of the urethra. The dorsal part of the external urethral sphincter was found to be thin at the point of attachment of the rectourethralis muscle, the ventral part of the longitudinal muscle of the rectum. We identified a venous plexus from the NVB located close to the oral and ventral side of the deep transverse perineal muscle. Many vascular branches from the NVB were found to be penetrating the longitudinal muscle and the ventral part of rectourethralis muscle at the level of the apex of the prostate. The rectourethral muscle was wrapped ventrally around the membranous urethra and apex of the prostate. The boundary between the longitudinal muscle and prostate gradually became more distinct, being located at the anterior end of the transabdominal dissection plane. (3) Histological examination showed that the dorsal part of the external urethral sphincter (striated muscle) is thin adjacent to the striated muscle fibers from the deep transverse perineal muscle and the NVB dorsally and close by. The rectourethral muscle was found to fill the space created by the internal anal sphincter, deep transverse perineal muscle, and both levator ani muscles. Many tortuous vessels and tiny nerve fibers from the NVB were identified penetrating the muscle fibers of the deep transverse perineal and rectourethral muscles. The structure of the superficial transverse perineal muscle was typical of striated muscle. These findings were reconstructed three-dimensionally. Conclusions: In intersphincteric resection or abdominoperineal resection for very low rectal cancer, the anterior dissection plane behind Denonvilliers' fascia disappears at the level of the apex of the prostate. The prostate and both NVBs should be used as landmarks during transanal dissection of the non-surgical plane. The rectourethralis muscle should be divided near the rectum side unless tumor involvement is suspected. The superficial and deep transverse perineal muscles, as well as their supplied vessels and nerve fibers from the NVB. In addition, the cutting direction should be adjusted according to the anorectal angle to minimize urethral injury.
Humans ; Male ; Rectum/surgery* ; Anal Canal/anatomy & histology* ; Rectal Neoplasms/surgery* ; Proctectomy ; Urethra/surgery*

The successful report of total mesorectal excision (TME)/complete mesocolic excision (CME) has encouraged people to apply this concept beyond colorectal surgery. However, the negative results of the JCOG1001 trial denied the effect of complete resection of the "mesogastrium" including the greater omentum on the oncological survival of gastric cancer patients. People even believe that the mesentery is unique in the intestine, because they have a vague understanding of the structure of the mesentery. The discovery of proximal segment of the dorsal mesogastrium (PSDM) proved that the greater omentum is not the mesogastrium, and further revised the structure (definition) of the mesentery and revealed its container characteristics, i.e. the mesentery is an envelope-like structure, which is formed by the primary fascia (and serosa) that enclose the tissue/organ/system and its feeding structures, leading to and suspended on the posterior wall of the body. Breakdown of this structure leads to the simultaneous reduction of surgical and oncological effects of surgery. People quickly realized the universality of this structure and causality which cannot be matched by the existing theories of organ anatomy and vascular anatomy, so a new theory and surgical map- membrane anatomy began to form, which led to radical surgery upgraded from histological en bloc resection to anatomic en bloc resection.
Humans ; Fascia/anatomy & histology* ; Laparoscopy ; Lymph Node Excision/methods* ; Mesentery/surgery* ; Mesocolon/surgery* ; Omentum ; Serous Membrane ; Clinical Trials as Topic

Because the classification system of radical surgery for rectal cancer has not been established, it is impossible to select the appropriate surgical method according to the clinical stage of the tumor. In this paper, we explained the theory of " four fasciae and three spaces " of pelvic membrane anatomy and then combined this theory with the membrane anatomical basis of Querleu-Morrow classification for radical cervical cancer resection. Based on this theory and the membrane anatomy of Querleu-Morrow classification of radical cervical cancer resection, we proposed a new classification system of radical rectal cancer surgery based on membrane anatomy according to the lateral lymph node dissection range of the rectum. This system classifies the surgery into four types (ABCD) and defines corresponding subtypes based on whether the autonomic nerve was preserved. Among them, type A surgery is total mesorectal excision (TME) with urogenital fascia preservation, type B surgery is classical TME, type C surgery is extended TME, and type D surgery is lateral extended resection. This classification system unifies the anatomical terminology of the pelvic membrane, validates the feasibility of using the " four fasciae and three fascial spaces " theory to classify rectal cancer surgery, and lays the theoretical foundation for the future development of a unified and standardized classification of radical pelvic tumor surgery.
Female ; Humans ; Uterine Cervical Neoplasms ; Rectal Neoplasms/pathology* ; Rectum/anatomy & histology* ; Pelvis/innervation* ; Proctectomy