Translational Research in Anatomy最新文献

Sacroiliac (SI) joint fixation is a technique used for SI joint fractures, SI joint dislocations and sacral fractures. Sacral screws can be placed either into the S1 or the S2 vertebrae if S1 is insufficient. Malpositioning of the screws is a common surgical complication as sacral variations exists amongst populations. Complications associated with the misposition of screws can lead to injury of the sacral venous plexus, iliac vessels, or sacral nerve roots. Therefore, this study aimed to evaluate sacral variations in a South African sample by determining distances between the first and second sacral foramina and classifying the common types of sacra found.

A quantitative cross-sectional comparative study was conducted. One hundred and twenty (n = 120) dry human sacra and 11 formalin-fixed cadavers were measured to determine the linear distances between the first two anterior and posterior sacral foramina. Additionally, the dry human sacra were classified according to Mahato's classification system. A cadaver SI joint fixation simulation was performed by an orthopaedic surgeon.

The mean sacral promontory height was found to be 31.81 mm and 37.52 mm in osteological and cadaver specimens, respectively. The mean anterior pedicle height was significantly different for the left (18.81 mm) and right (21.67 mm) side measurements. A statistically significant difference was found between cadavers and osteological samples for all measurements taken. In the osteological sample, ancestry and age mostly influenced the variations noted.

Using Mahato's classification system, sacra with five sacral segments, auricular surfaces extending from the superior part of S1 to the middle of S3 and no accessory L5/S1 articulations had the highest prevalence of 59.17 %.

The South African sample exhibited similarities but did not fully compare to other populations. The results in this study should be considered as a reference for surgeries involving the SI joint and sacral foramina. However, where possible, the exact anatomy with possible variations of the patient should be evaluated preoperatively using X-rays and angiograms.

Introduction

The present study evaluated the consistency and reliability of five anatomical landmarks in the external auditory meatus using CBCT (cone beam computed tomography) scans. The goal was to determine if these landmarks could reliably replace the commonly used point Porion for superimposing CBCT scans in clinical practice. Consistent anatomical features in the external auditory meatus are essential for accurate cranial assessments in dentistry and medicine. Despite their importance, these features have been underexplored, making this study a valuable contribution to improving clinical evaluation accuracy.

Materials and methods

22 CBCT scans were analyzed using ITK-Snap software. The shape of the External Auditory Meatus had been rendered by segmentation. These segmentations were used as a basis to locate the landmarks. The spread in location of the suggested landmarks concerning a reference coordinate system was treated as a measure for consistency. For that purpose, the absolute mean distance from all registered landmarks to the center of the location cloud was calculated for each dataset.

Results

The smallest spread in locations was measured for the so-called Epitympanic Notch, with 4.3 mm on average (SD 1.7). However, recognizing this landmark in the segmented images appeared to be relatively difficult. The landmark with the second smallest spread in locations (4.4 mm (SD 2.2)) and an easier recognition in the segmented image was the most superior point of the external auditory meatus. The most inferior point appeared to be the least reliable of all five landmarks.

Conclusion

Based on the present study, a consistently reliable landmark in the External Auditory Meatus to replace point Porion could not be identified. The hypothesis that any landmark could suffice for superimposing CBCT scans was not confirmed.

Background

Arterial morphology varies and changes with increasing age. This may challenge the success of endovascular procedures and influence candidate selection. The study aimed to determine the mean dimensions, tortuosity severity, and tortuosity phenotype of the iliofemoral pathway of adult males and females from a South African sample. Furthermore, the relationship between increased age and changes in vessel morphology was investigated.

Design

A retrospective cross-sectional study was conducted using a sample of 224 (117 males and 107 females) computed tomography angiograms of patients hospitalized due to traumatic injuries (aged 18–80 years), accessed from Tygerberg Hospital, Cape Town, South Africa.

Methods

The arterial lengths and lumen diameters of the common iliac (CIA), external iliac (EIA), and femoral arteries (FA) were measured. Tortuosity severity was described by visual estimation and quantified using the tortuosity index (TI) and inflection count metric (ICM). The data were compared between right and left sides of the body, the sexes, and age categories.

Results

On average, the common iliac artery was the widest (9.50 ± 1.53 mm), while the external iliac artery was the longest (110.89 ± 16.04 mm). Bilateral asymmetries were observed. Arterial diameters were larger in males. Regression analysis revealed a strong positive relationship between arterial tortuosity and increasing age, particularly in females. Tortuosity was most frequently observed in the external iliac artery. However, the c-shaped curving tortuosity phenotype was observed in all three arteries investigated.

Conclusion

The morphology of the iliofemoral arterial pathway varied bilaterally, between the sexes, and with increased age. These findings align with previous studies, noting the variable morphology of the iliofemoral pathway, in countries outside of Sub-Saharan Africa. Sex- and age-specific descriptions of arterial anatomy may enhance the safety of endovascular procedures and interventions. These descriptions contribute towards the development of a reference database of typical arterial anatomy in South Africa, ultimately assisting with patient selection and the identification of vascular pathologies.

Background

The clivus, a key skull base structure for neurosurgeons due to its proximity to brainstem areas, is formed by the fusion of two bones. A rare variation, the canalis basilaris medianus (CBM) or clival canal, can exist within the occipital bone. The clivus has a rich venous network, and the CBM's presence might be linked to veins or embryonic structures. Understanding the CBM is valuable for interpreting clival fractures and during neurosurgery. This study aimed to determine the frequency and morphometric parameters of the CBM.

Material and methods

Fifty-nine dry adult skulls were selected for the investigation. Morphometric measures included establishing the diameters of the internal and external foramina of the CBM, the length of the canal, and its distance from the foramen magnum (FM), jugular tubercles, and lateral margins of the basilar part of the occipital bone.

Results

Out of the 59 skulls investigated, only a single specimen contained the CBM. Thus, the frequency of canal presence in our sample was 0.59 %. The internal foramen of the CBM was located on the internal surface of the clivus, 4.03 mm anteriorly to the FM with a diameter of 2.84 mm. Further, the canal passed through the clivus and had its external foramen on the external surface of the clivus at 0.11 mm above the pharyngeal tubercle and its distance from the FM was 9.19 mm. The length of the CBM was established at 8.16 mm.

Conclusion

The CBM is a rare variation of the basilar part of the occipital bone. Therefore, the possibility of the existence of this variation should be considered when analyzing CT and MRI images to avoid misinterpretation of their results and during surgical interventions in this area.

Background

The facial canal lies in the petrous part of the temporal bone and contains the facial nerve. The facial canal and nerve are divided into three segments: the labyrinthine, tympanic and mastoid segments, which travel in different planes. These segments are closely related to the structures of the middle- and inner-ear, so pathology of the intracranial facial nerve is often evident in cochlear implant users. The facial canal and nerve are of great concern to otologists during electrode placement for a cochlear implant, as any damage to the nerve may result in untreatable facial paralysis. Few studies have been conducted on a cadaveric population, with most carried out on CT images of the cochlea and facial nerve. Thus, there is no standard or straightforward methodology to visualise the facial canal and nerve directly. We propose a detailed dissection technique to bridge this gap in research.

Method

Four cadavers were used, and both the left and right facial canals were dissected. After the exposure of the cranial floor, the internal acoustic meatus and the facial canal were dissected out using drilling tools to remove the surrounding temporal bone and expose the facial nerve within the facial canal.

Results

This technique allowed for morphometric analyses and observations of the facial canal in relation to the middle- and inner-ear.

Conclusion

Knowledge of the facial canal may assist otosurgeons in safely dissecting the region without injuring vital structures within this area.

Introduction

The development of anatomy can be contributed to in various ways. Throughout history, anatomy has essentially been governed by men. Little is said about the women without whom the teaching of anatomy would not have been possible - women who donated their bodies so that others could learn from them – women donors.

Aims

This study aims to analyse the donor base, focusing on women donors who joined the Conscious Body Donation Programme at the Medical University of Silesia in Katowice and declared donation of their bodies for scientific and teaching purposes. The principles of the Conscious Body Donation Programme in Poland are also discussed using the example of the Medical University of Silesia in Katowice, which initiated the programme in 2003.

Materials and methods

The analysis covered the donors database maintained at the Medical University of Silesia from 2000 till now. The study included such aspects as the number of declarations made, gender, age of donors, number of resignations from the body donation program, and the number of withdrawals by the university from accepting a donor's body. The results obtained were subjected to statistical analysis.

Results

Among 2091 donors, 53.12 % were female (n = 1589) and 46.88 % were male (n = 1402). The number of declarations has been steadily increasing since 2000. Analysing the number of declarations made by women - the highest number of declarations was made in 2009 (n = 112), 2017 (n = 191), and 2023 (n = 123 declarations). The average age at which women made declarations was 63.12 ± 13.82 years. The mean age of death was 78 ± 10.48 years with the mean age of death of all donors being 75.7 ± 10.81 years. The minimum age of declaration was 18 years, the maximum was 98 years. When analysing the age ranges in which pledges were made, women were most likely to pledge between 60 and 70 years of age (525 declarations). By 2024, 51 women had resigned from becoming donors. The average age of resignation is 63.75 ± 13.52 years. The minimum age of resignation was 26 years and the maximum was 87 years.

Conclusions

Currently, medical knowledge is growing rapidly. The nobility of donors, including female donors, who choose to donate their bodies for scientific and teaching purposes, reaches far beyond the grave. Such women live on forever remembered by students and then by doctors, physiotherapists, nurses and midwives in a variety of working circumstances often saving human lives, because no teaching aid can illustrate the human body as perfectly as the human body.

Background

Evaluating ulnar variance (UV) and triangular fibrocartilage complex (TFCC) is crucial since they might have dual effects on the wrist structure and function. This study aims to assess some anthropometric measurements of the wrists of the Saudi population using MRI.

Materials and methods

A cross-sectional retrospective study was conducted on 64 wrist normal MR images. Sociodemographic characteristics were retrieved and kept confidential. Image analysis was performed on Digital Imaging and Communications in Medicine files. UV and TFCC thickness and angle were measured in the same slice. Statistical analysis was conducted, and a significance <0.05 was considered.

Results

The ages of the selected sample ranged from 18 to 67 years; 45 were males, and 19 were females with 32 right and 32 left wrists. The cases showed 59.4 % negative UV and 40.6 % positive UV (mean ± SD of −2.24 ± 0.55 and 1.59 ± 0.48). TFCC thickness mean ± SD of 2.34 ± 0.61, and its angle mean ± SD of 32.39 ± 4.68. Significant differences were elaborated between the positive and negative UV population in the means of UV, TFCC thickness, and angle (p < 0.001). Also, age-dependent significant differences were detected in the UV value and TFCC thickness (p = 0.042 and 0.013). Correlation and linear regression showed substantial relations between UV and TFCC thickness and angle. Also, TFCC thickness with the angle.

Conclusion

This study provided a valuable guide for evaluating and managing wrist problems in Saudis and primary data for further investigations.

Background

For many years, sex determination has been achieved through analysis of skeletal remains in forensic medicine. The patella can be utilized for sex determination in the absence (or damage) of the cranium, upper and lower limbs, and pelvic bones. Additionally, understanding the patella's morphology and morphometry is essential for diagnosing and treating injuries and disorders of the knee joint, as well as knee arthroplasty and patella ligament grafting (Medeiros et al., 2001). This study reviewed the morphology and morphometry of the patella in a Black African population of KwaZulu-Natal and determined if a correlation between the parameters of the patellae and sex exists.

Materials and methods

154 dry patellae belonging to a South African black population group were utilized to review their morphology and morphometry. The classifications of Wiberg (1941) and Borges et al. (2016) were adapted for the morphology. The seven morphometric measurements were adapted from Dayal and Bidmos (2005) and Borges et al. (2016). A p-value less than 0.05 was considered statistically significant.

Results

According to the Wiberg classification: Type 1 patellae were least prevalent (1.9 %), while Type 2 were most common with an incidence of 59.7 %. No statistical difference was recorded with sex (p-value = 0.517). According to Borges et al. (2016) classification: Type 1 (triangular-shaped) patellae were most prevalent in males and females (72.7 %) and Type 3 (irregular shape) patellae were least common in this study. A statistically significant difference between Borges et al. (2016) classification scheme (shape of the patella) and sexes was recorded (p-value = 0.003). A statistically significant relationship between morphometric parameters of the patella and sex was also recorded (p-value <0.001). Patella measurements were greater in males than in females.

Conclusion

In this study, the patella displayed sexually dimorphic morphological and morphometric characteristics, which indicated that the patella may be used for sex determination in forensic cases with the KwaZulu-Natal population of South Africa, in addition to clinical applications such as knee arthroplasty, patellar ligament grafting, prosthesis synthesis, and patellar implants.

Background

The interaction of cell populations and synchronization of cell signaling pathways during craniofacial development can cause malformations such as facial clefts when interrupted by teratogenic agents including synthetic corticosteroids. Therefore, this study aimed to determine the potentially disturbing dexamethasone (Dex) effect on palatal shelf development in rat embryos and the possible reasons for this teratogenic potential in relation to fibroblast growth factor 10 (FGF10) as well as FGF10 receptor2 (FGFR2) signaling.

Methods

Thirty pregnant rats were used, which were then randomly categorized into three groups of ten animals each: the control group, where pregnant rats received no treatment, Sham group in which pregnant rats were injected subcutaneously with saline (0.4 mg/kg body weight) during the mid-pregnancy period at gestational day 9–14, and Dex-treated group, where pregnant rats received 0.4 mg/kg of Dex at mid-gestational period. Pregnant animals from all groups were sacrificed on day 20 of gestation before birth and the fetuses were removed for examination of the palatal shelves using a light microscope (LM). In addition, a real-time polymerase chain reaction and a reverse transcription-polymerase chain reaction (RT-PCR) were done to evaluate FGF10 and its receptor FGFR2 gene expression.

Results

The cleft palate incidence rates in the groups of embryos were determined. Only the offspring in the Dex group showed a cleft palate. Moreover, the cleft palate incidence rate in the Dex group was significantly different compared to controls. Moreover, a significant decrease in FGF10 and FGFR2 expression levels was reported in the Dex group than in the controls.

Conclusions

Dex treatment in mid-gestation may increase the incidence of cleft palate development, which may be due to modulation of FGF signaling. This calls for caution when using this medication in the first half of pregnancy unless absolutely necessary and under close medical supervision.