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. 

Glaucoma is the leading cause of irreversible blindness worldwide, with its primary risk factor arising from elevated intraocular pressure (IOP) due to an imbalance between aqueous humor production and outflow. This study aims to establish quantitative correlations among IOP, iris mechanical properties, channel microstructures, and aqueous humor dynamics through three-dimensional modeling and finite element analysis, overcoming the limitations of conventional experimental techniques in studying aqueous flow within the trabecular meshwork (TM) outflow pathway. A three-dimensional fluid-structure interaction (FSI) model incorporating the layered TM structure, Schlemm's canal (SC), iris, and other anterior segment tissues was developed based on human ocular anatomy. FSI simulations were performed to quantify the effects of IOP variations and iris Young's modulus on tissue morphology and aqueous humor dynamics parameters. The computational results demonstrated that axial iris deformation showed significant correlations with IOP and iris Young's modulus. Although elevated IOP exhibited minimal effects on hydrodynamic parameters in the anterior and posterior chambers, it markedly suppressed aqueous flow velocity in the TM region. Additionally, wall shear stress in SC and collector channels displayed high sensitivity to IOP variations. These findings reveal that the tissue mechanics-FSI mechanism modulates outflow resistance by regulating aqueous humor dynamics, offering valuable references for developing clinical therapies targeting IOP reduction in glaucoma management.
Humans ; Trabecular Meshwork/anatomy & histology* ; Finite Element Analysis ; Aqueous Humor/metabolism* ; Intraocular Pressure/physiology* ; Glaucoma/physiopathology* ; Iris/anatomy & histology* ; Computer Simulation ; Models, Biological

The orientation of the acetabular cup in hip joint anteroposterior radiograph is a key factor in evaluating the postoperative outcomes of total hip arthroplasty (THA). Currently, measurement of the acetabular cup anteversion angle primarily relies on manual drawing of auxiliary lines by orthopedic surgeons and calculations using scientific calculators. This study proposes an automated computer-aided measurement method for the acetabular cup anteversion angle based on hip joint anteroposterior radiograph. The proposed method segments hip prosthesis images using an improved Otsu algorithm, identifies feature points at the acetabular cup opening by combining circle-fitting theory and the cup's geometric characteristics, and fits an ellipse to the cup opening to calculate the anteversion angle. A total of 104 hip joint anteroposterior radiographs, including 71 right-sided and 81 left-sided prostheses, were analyzed. Two orthopedic surgeons independently measured the postoperative anteversion angles, and the results were compared with computer-generated measurements for correlation analysis. Spearman and Pearson correlation analyses demonstrated significant correlations between the proposed method and manual measurements for both the right group ( r = 0.795, P < 0.01) and the left group ( r = 0.859, P < 0.01). This method provides a reliable reference for orthopedic surgeons to assess postoperative prognosis.
Humans ; Acetabulum/anatomy & histology* ; Arthroplasty, Replacement, Hip/methods* ; Algorithms ; Hip Prosthesis ; Hip Joint/diagnostic imaging* ; Radiography ; Image Processing, Computer-Assisted/methods*

OBJECTIVE: To measure and analyze the relationships among the posterior tibial slope (PTS), meniscal slope (MS), and meniscus posterior horn thickness (MPHT) of the medial and lateral tibial plateau in healthy people and patients with anteromedial osteoarthritis (AMOA) in Heilongjiang province, so as to provide reference basis for appropriate tibial osteotomy and prosthesis placement angles in knee joint surgeries. METHODS: A retrospective collection of imaging data from knee joint MRI examinations conducted prior to AMOA for various reasons was performed. A total of 103 healthy individuals (healthy group) and 30 AMOA patients (AMOA group) were included. There was no significant difference in the gender composition ratio, side, and body mass index between the two groups ( P>0.05); however, the comparison of ages between the two groups showed a significant difference ( P<0.05). The collected DICOM format image data was imported into the RadiAnt DICOM Viewer software and measured the medial PTS (MPTS), lateral PTS (LPTS), medial MS (MMS), lateral MS (LMS), medial MPHT (MMPHT), and lateral MPHT (LMPHT) with standard methods. The differences of the above indexes between the two groups and between different genders and sides in the two groups were compared, and Pearson correlation analysis was carried out. At the same time, the measured data of healthy group were compared with the relevant literature reported in the past. RESULTS: Compared to the healthy group, the AMOA group exhibited significantly smaller MPTS and LPTS, as well as significantly greater MMPHT and LMPHT, with significant differences ( P<0.05). However, there was no significant difference in the MMS and LMS between the two groups ( P>0.05). The differences in various indicators between genders and sides within the two groups were not significant ( P>0.05). The correlation analysis and regression curves indicated that both MPTS and LPTS in the two groups were positively correlated with their respective ipsilateral MS and MPHT ( P<0.05); as PTS increased, the rate of increase in MS and MPHT tend to plateau. Compared to previous related studies, the MPTS and LPTS measured in healthy group were comparable to those of the Turkish population, exhibiting smaller values than those reported in other studies, while MMS and LMS were relatively larger, and MMPHT and LMPHT were smaller. CONCLUSION In healthy people and AMOA patients in Heilongjiang province, PTS has great individual differences, but there is no significant individual difference in MS. MPHT can play a certain role in retroversion compensation, and its thickness increase may be used as one of the indicators to predict the progression of AMOA. The above factors should be taken into account when UKA is performed, and the posterior tilt angle of tibial osteotomy should be set reasonably after preoperative examination and evaluation.
Humans ; Osteoarthritis, Knee/surgery* ; Retrospective Studies ; Tibia/pathology* ; Male ; Female ; Adult ; Menisci, Tibial/anatomy & histology* ; China ; Knee Joint/pathology* ; Magnetic Resonance Imaging ; Middle Aged ; Aged ; Osteotomy

OBJECTIVE: To investigate the impact of bone mass and volume of low-density zones beneath the tibial plateau on the maximum von Mises stresses experienced by the cartilage and meniscus in the knee joint. METHODS: The study included one healthy adult volunteer, from whom CT scans were obtained, and one patient diagnosed with knee osteoarthrisis (KOA), for whom X-ray films were acquired. A static model of the knee joint featuring a low-density zone was established based on a normal knee model. In the finite element analysis, axial loads of 1 000 N and 1 800 N were applied to the weight-bearing region of the upper surface of the femoral head for model validation and subsequent finite element studies, respectively. The maximum von Mises stresses in the femoral cartilage, as well as the medial and lateral tibial cartilage and menisci, were observed, and the stress percentage of the medial and lateral components were concurrently analyzed. Additionally, HE staining, as well as alkaline magenta staining, were performed on the pathological specimens of patients with KOA in various low-density regions. RESULTS: The results of model validation indicated that the model was consistent with normal anatomical structures and correlated with previous calculations documented in the literature. Static analysis revealed that the maximum von Mises stress in the medial component of the normal knee was the lowest and increased with the advancement of the hypointensity zone. In contrast, the lateral component exhibited an opposing trend, with the maximum von Mises stress in the lateral component being the highest and decreasing as the hypointensity zone progressed. Additionally, the medial component experienced an increasing proportion of stress within the overall knee joint. HE staining demonstrated that the chondrocyte layer progressively deteriorated and may even disappear as the hypointensity zone expanded. Furthermore, alkaline magenta staining indicated that the severity of microfractures in the trabecular bone increased concurrently with the expansion of the hypointensity zone. CONCLUSION The presence of subtalar plateau low-density zone may aggravate joint degeneration. In clinical practice, it is necessary to pay attention to the changes in the subtalar plateau low-density zone and actively take effective measures to strengthen the bone status of the subtalar plateau low-density zone and restore the complete biomechanical function of the knee joint, in order to slow down or reverse the progression of osteoarthritis.
Humans ; Finite Element Analysis ; Knee Joint/physiology* ; Tibia/anatomy & histology* ; Cartilage, Articular/physiology* ; Menisci, Tibial/physiopathology* ; Tomography, X-Ray Computed ; Osteoarthritis, Knee/diagnostic imaging* ; Weight-Bearing ; Bone Density ; Adult ; Stress, Mechanical ; Male ; Middle Aged ; Biomechanical Phenomena ; Female

OBJECTIVE: To explore the anatomical parameters of the cervical uncinate process "inflection point" through cervical CT angiography (CTA) and MRI measurements, offering a reliable and safe anatomical landmark for anterior cervical decompression surgery. METHODS: A retrospective analysis was conducted on the cervical CTA and MRI imaging data of normal adults who met the selection criteria between January 2020 and January 2024. The CTA dataset included 326 cases, with 200 males and 126 females, aged 22-55 years (mean, 46.7 years). The MRI dataset included 300 cases, with 200 males and 100 females, aged 18-55 years (mean, 43.7 years). Based on the CTA data, three-dimensional models of C ₃-C ₇ were constructed, and the following measurements were obtained from the superior view: uncinate process "inflection point" to vertebral artery distance (UIVD), uncinate process tip to vertebral artery distance (UTVD), uncinate process "inflection point" to "inflection point" distance (UID), uncinate process long-axis to sagittal angle (ULSA), and uncinate process "inflection point" to transverse foramen-sagittal angle (UITSA). From the anterior view, the anterior uncinate process to sagittal angle (AUSA) was measured. From the posterior view, the posterior uncinate process to sagittal angle (PUSA) was measured. Based on the MRI data, uncinate process "inflection point" to dural sac distance (UIDD) and dural sac width (DSW) were measured. The trends in measurement parameters of C ₃-C ₇ were observed, and the differences in measurement parameters between genders and between the left and right sides of the same segment were compared, as well as the difference in UID and DSW within the same segment was compared. RESULTS: The measurement parameters from C ₃ to C ₇ in the CTA data showed a general increasing trend, with no significant difference between the left and right sides within the same segment ( P>0.05). The UIVD, UTVD, and UID were greater in males than in females, with significant differences observed in the UIVD and UTVD at C ₃ and C ₆ and UID at C ₃, C ₆, and C ₇ ( P<0.05). The MRI measured DSW showed a general increasing trend from C ₃ to C ₇, and the DSW at C ₆ was greater in females than in males, with a significant difference ( P<0.05). The UIDD showed a gradual decreasing trend, with the smallest value at C ₆. There was no significant difference between males and females or between the left and right sides within the same segment ( P>0.05). The UID was greater than the DSW at C ₃-C ₇, and the differences were significant ( P<0.05). CONCLUSION The uncinate process "inflection point" is a constant anatomical structure located at the anteromedial aspect of the uncinate process tip and laterally to the dural sac. It maintains a certain safe distance from the vertebral artery. As a decompression landmark in anterior cervical spine surgery, it not only ensures surgical safety but also guarantees complete decompression.
Humans ; Adult ; Male ; Female ; Middle Aged ; Retrospective Studies ; Cervical Vertebrae/surgery* ; Magnetic Resonance Imaging ; Decompression, Surgical/methods* ; Young Adult ; Adolescent ; Computed Tomography Angiography ; Imaging, Three-Dimensional ; Vertebral Artery/anatomy & histology* ; Anatomic Landmarks/diagnostic imaging*

OBJECTIVE: To explore the morphological characteristics of the postero-superior protuberance of the calcaneus and to explore its relationship with Haglund malformation. METHODS: Ankle lateral X-ray films of 391 hospitalized patients between May 2021 and June 2024 were retrospectively collected. The morphological parameters of the postero-superior protuberance of the calcaneus were measured, including the length of the base, the height of the base, and the tip angle of the postero-superior protuberance of the calcaneus, and the morphological types were classified according to the above parameters, including the peak type, the hill type, and the flat type. The related parameters of Haglund malformation were measured, including Fowler-Philipp angle (FPA), calcaneal pitch angle (CPA), parallel pitch line (PPL), Chauveaux-Liet angle (CLA), and X/Y ratio (total calcaneal length/length of greater tuberosity of calcaneus). The differences of the morphological parameters of the postero-superior protuberance of the calcaneus and the related indicators of Haglund deformity among the three types and between the males and the females were compared and analyzed, and the differences of the positive numbers of the related indicators of Haglund deformity among the three types were compared. RESULTS: According to the morphological parameters of the postero-superior protuberance of the calcaneus, there were 64 cases of peak type, 245 cases of hill type, and 82 cases of flat type. There was no significant difference in the length of the base of the postero-superior protuberance of the calcaneus, CPA, CLA, and X/Y ratio among the three types ( P>0.05). Among the three types, the peak type had the largest FPA and the flat type had the smallest ( P<0.05); the peak type had the smallest tip angle of the postero-superior protuberance of the calcaneus and the flat type had the largest ( P<0.05); the positive rate of PPL in the hill type was significantly higher than that in the peak type and flat type ( P<0.05); the height of the base of the postero-superior protuberance of the calcaneus in the flat type was the smallest ( P<0.05). FPA, CPA, CLA, PPL, and X/Y ratio were positive in 2, 42, 172, 142, and 77 patients, respectively. There was no significant difference in the number of positive Haglund deformity indicators among the three types ( P>0.05). There was no significant difference between male and female patients in the tip angle of the postero-superior protuberance of the calcaneus, FPA, the positive rate of PPL, and X/Y ratio ( P>0.05). The length and the height of the base of the postero-superior protuberance of the calcaneus, CPA, and CLA in male patients were significantly higher than those in female patients ( P<0.05). CONCLUSION The postero-superior protuberance of the calcaneus can be divided into three types: the peak type, the hill type, and the flat type. The peak type is more likely to suffer from Haglund deformity, and the males are more likely to suffer from Haglund deformity than the females.
Humans ; Calcaneus/anatomy & histology* ; Male ; Female ; Retrospective Studies ; Adult ; Middle Aged ; Adolescent ; Young Adult ; Radiography ; Child ; Aged

OBJECTIVE: This study aimed to evaluate the relationships of white blood cell (WBC) count, platelet (PLT) count, and PLT-to-WBC ratio (PWR) with muscle mass in Chinese older adults. METHODS: This cross-sectional analysis involved 4,033 Chinese older adults aged ≥ 65 years from the Healthy Ageing and Biomarkers Cohort Study. Muscle mass and total skeletal muscle mass index (TSMI) were measured by bioelectric impedance analysis. WBC, PLT, and PWR were measured using standard methods. Multivariate linear regression was used to examine the associations of WBC count, PLT count, and PWR with TSMI. RESULTS: High WBC count, PLT count, and PWR were associated with low TSMI, with coefficients of -0.0091 (95% confidence interval [ CI]: -0.0142 to -0.0041), -0.0119 (95% CI: -0.0170 to -0.0068), and -0.0051 (95% CI: -0.0102 to -0.0001). The associations between the three inflammatory indices and TSMI were linear. Stratified analyses indicated that the relationship between inflammatory markers and TSMI was more evident in male participants and in individuals aged < 80 years than in their counterparts. CONCLUSION Elevated WBC count, PLT count, and PWR correlated with muscle mass loss. This study highlights the importance of regular monitoring of inflammatory markers as a potential strategy for the screening and management of sarcopenia in older adults.
Humans ; Aged ; Male ; Female ; China ; Leukocyte Count ; Cross-Sectional Studies ; Platelet Count ; Aged, 80 and over ; Muscle, Skeletal/anatomy & histology* ; Independent Living ; Blood Platelets ; Leukocytes ; Sarcopenia

The current low quality of fixed restoration margins is highly correlated with the high incidence of margin-related complications. It is also related to the unclear spatiotemporal geometric position relationship among the consensus definitions of the gingival margin (G), preparation margin (P), and restoration margin (R). This paper discusses the existing problem of the existing term "gingival margin" as a surface anatomical landmark; proposes the term "free gingival margin line" that conforms to geometry and measurement and has importance as a surface anatomical landmark; and clarifies the participants that exist in the marginal area. These participants include the P, R, and G; cementation (adhesive) layer; and gingival sulcus. Moreover, this paper discusses the various iatrogenic damages induced by entering the gingival sulcus via the P, R, and cementing (adhesive) layer. Through the discussion of the design deficiencies of the subgingival and biologically oriented preparation technique, the physiological and clinical importance of the concept of gingival sulcus/gingival sulcus fluid + supercrestal tissue attachment (biological width) = first periodontal protective barrier was analyzed. The value of preserving the physiological role of the gingival sulcus is emphasized. Furthermore, the newly defined RPG distance represents the distance between the successive P or R line and free G line and can be measured in the clinical procedure of tooth preparation. The optimal solution is 0-200 µm, that is, RPG200: the P and R are located on the free G line and the distance between these margins is less than 200 µm. This distance not only has the aesthetic effect of invisibility to the naked eye, it also has a minimal effect on the G and gingival sulcus and is convenient for doctors and patients to clean. Furthermore, in accordance with the positional relationship between the three margins and cementation (adhesive) layer, a new classification of marginal positions is proposed. This classification overcomes the problems of incomplete inclusion objects and uncontrolled risk factors in the previous classification. It also has the advantages of strong practicability, good efficiency of main control geometric quantity, and clear risk control points. The new design scheme and classification of the margi-nal position of RPG200 proposed in this paper provide a new understanding for margin design and complication prevention in the future.
Humans ; Gingiva/anatomy & histology* ; Cementation ; Dental Restoration, Permanent/methods*

OBJECTIVES: Digitally collect data on the preparation space of the molar occlusal surface for full crown restoration and analyze the minimum preparation spaces and areas prone to insufficient preparation. METHODS: A total of 846 molars (excluding third molars) designated for repair with zirconium dioxide crowns were selected. All molars were prepared by using the fixed-depth groove method under visual guidance. A digital impression was collected, and the occlusal surface of the preparation was divided into regions: mesiobuccal area, mesiolingual area, distobuccal area, distolingual area, mesial marginal ridge, and distal marginal ridge. Image measurement software (3Shape Unite) was employed to record the smallest preparation space on the molar occlusal surface, and a space of <1 mm was defined as insufficient preparation. The chi-square test was utilized for the statistical analysis of data. RESULTS: Significant differences were observed in the areas with the smallest preparation space on the occlusal surface of molars across different quadrants (P<0.05). Notably, the area with the smallest preparation space on the occlusal surface of the maxillary first molar was most frequently found in the mesiobuccal area, whereas the smallest preparation spaces on other molars were predominantly located in the distolingual area. The insufficient preparation of the occlusal surface occurred in 41.0% (347 cases) of teeth. The distribution of prone areas corresponded with the distribution of the smallest spatial areas. CONCLUSIONS Although the fixed-depth groove method is employed, the preparation space on the molar surface unavoidably remains uneven under visual guidance. The identification of the areas prone to minimum preparation spaces can serve as a valuable guide for clinicians to prevent insufficient preparation.
Humans ; Molar/anatomy & histology* ; Crowns ; Zirconium