Fibularis brevis tendon (FBT) variants are under-recognised and may alter both imaging interpretation and operative strategy. The purpose of this review was to synthesise the available anatomical, radiological, and surgical literature on distal FBT variants and to frame this evidence through a classification-based approach. This study was designed as a narrative review. Anatomical/cadaveric, imaging, and surgical publications relevant to distal FBT morphology and clinical interpretation were synthesised using the Olewnik classification as the organising framework. No formal systematic-review protocol or meta-analysis was undertaken. The available literature describes two main distal attachment types of the FBT: Type I and Type II, the latter further subdivided into subtypes IIa-IIc. The most consistent findings concern recognition of accessory slips and fused components, differentiation of variants from longitudinal split tears or pseudomass-like findings, and appreciation of how atypical insertions may influence distal operative exposure. The strongest evidence remains anatomical and imaging-based, whereas direct validation of classification-guided treatment is still limited. The Olewnik classification provides a useful anatomical framework for radiological reporting and preoperative planning, but it should presently be regarded as clinically promising rather than fully validated. A structured, variant-aware interpretation can improve communication and operative preparation in patients with lateral ankle pain, tendon pathology, or instability.
The mastoid emissary vein (MEV), mastoid emissary canal (MEC), and mastoid emissary foramen (MEF) are common but variably reported structures of the mastoid-posterior fossa region. Existing literature is fragmented across osteological, imaging-based, and clinical studies, with inconsistent prevalence and morphometric estimates, and with limited integration of anatomical variation into surgical and radiological decision-making. This SANRA-guided narrative review aimed to synthesise the anatomy, variability, imaging assessment, and clinical implications of MEV/MEC/MEF. This SANRA-guided narrative review synthesised anatomical, imaging, and clinical studies identified through PubMed/MEDLINE, Scopus, and Google Scholar from database inception through March 2026. Eligible studies included dry-skull, cadaveric, CBCT, MDCT/HRCT, and case-based reports addressing morphology, morphometrics, prevalence, or clinical relevance. Owing to methodological heterogeneity, findings were synthesised narratively. Across osteological and imaging studies, MEF/MEC prevalence was generally high but heterogeneous, with frequent unilateral or bilateral multiplicity. Most canals/foramina were small, whereas a minority were markedly enlarged and potentially relevant to surgical bleeding, collateral venous drainage, or venous pulsatile tinnitus. Enlarged MEVs have been implicated in selected cases of venous pulsatile tinnitus, with reported treatments including conservative management, surgical clipping/ligation, and endovascular or percutaneous occlusion. In mastoid and posterior fossa surgery, prominent MEVs have been reported as potential sources of difficult venous bleeding. In paediatric Osia implantation, larger preoperative MEV calibre correlated with intraoperative bleeding. MEV/MEC/MEF should be assessed systematically on preoperative imaging, including presence, number, calibre, and relationships to surgical landmarks. Consistent reporting may reduce avoidable haemorrhagic and diagnostic complications.
To prospectively evaluate the intraoperative relationship between the retromandibular vein (RMV) and the marginal mandibular branch (MMB) or inferior facial nerve division during parotidectomy, and to synthesize the relevant anatomical and surgical literature. Consecutive parotidectomy procedures performed over a one-year period were prospectively evaluated. The RMV-MMB/inferior facial nerve relationship was recorded intraoperatively, and variants were photographed and documented. A structured narrative literature review was performed to identify cadaveric, fetal, radiological, surgical series, and case reports describing RMV-facial nerve relationships. During this period, 44 parotidectomies were performed; the final anatomical analysis included the 35 cases in which the RMV-MMB/inferior facial nerve relationship could be clearly defined. Thirty-five parotidectomy procedures were evaluated. The classical configuration, defined as the RMV deep/medial to the MMB or inferior facial nerve division, was observed in 27 cases (77.1%). Eight variants (22.9%) were documented: four cases (11.4%) showed MMB interposition between the superficial temporal vein and maxillary vein, and four cases (11.4%) showed a cervicofacial branch coursing deep/medial to the RMV. Across the literature review and the present cohort, 1454 sides/cases were summarized, including 1346 classical configurations (92.6%) and 108 variants (7.4%). Among these 35 cases, facial nerve dissection was performed anterogradely in 33 cases and retrogradely in 2 cases; both retrograde cases showed the classical relationship. The RMV is a useful landmark during parotidectomy, especially in retrograde dissection, but its relationship with the MMB and inferior facial nerve division is not constant. Awareness of interposition and deep/medial nerve variants may help reduce the risk of venous bleeding, surgical-plane misidentification, and facial nerve injury.
Immersive virtual reality (VR) allows learners to interact with anatomical structures in three dimensions, potentially improving spatial understanding compared to traditional instructional methods. While VR is increasingly incorporated into medical curricula, prospective studies evaluating both learning outcomes and experiential measures remain limited. This study aimed to evaluate the impact of a single immersive VR anatomy session on knowledge acquisition, learner confidence, cognitive workload, and perceived immersion among first-year medical students. In this prospective educational intervention, first-year medical students at Kansas City University completed a standardized immersive VR anatomy module. Anatomy knowledge was assessed using a 20-item multiple-choice examination administered pre-session, immediately post-session, and at a 20-day follow-up. Learner confidence was measured using a 5-point Likert scale. Cognitive workload was assessed using the NASA Task Load Index (NASA-TLX), and immersion was measured using validated presence and usability items. Anatomy knowledge improved significantly from pre- to post-intervention (mean increase 7.2% points, 95% CI [3.9, 10.6], p < 0.001). However, scores declined at delayed follow-up (mean change - 15.3% points from post, 95% CI [-19.8, -10.7], p < 0.001), falling below baseline mean levels. Confidence demonstrated a significant upward shift in distribution (p = 0.018), although change in confidence was not associated with knowledge gain (p = 0.863). Cognitive workload was not significantly associated with learning outcomes, while small negative correlations were observed between knowledge gain and both presence (r = -0.31, p = 0.022) and usability (r = -0.28, p = 0.034). Immersive VR produces significant short-term improvements in anatomy knowledge and learner confidence but does not sustain retention following a single exposure. While effective for enhancing short-term anatomy knowledge and learner engagement, these findings suggest that immersive VR may be most effective when integrated as a complementary component within a multimodal anatomy curriculum rather than used as a standalone instructional modality.
This study aimed to characterize the pulmonary venous (PV) drainage patterns and left atrial (LA) morphologies, and to perform a detailed morphoanatomic analysis based on computed tomography angiography (CTA) data. Pulmonary CTA images of 204 adults (123 males, 81 females) were retrospectively analyzed. PV drainage patterns and LA morphological types were determined. In LAs with classical configuration, ostial diameters, interostial distances, transverse and vertical LA diameters, and angles between ostia and the y-axis as well as between the ostia themselves were measured. Measurements were compared by sex and side (right-left). The mean age was 54.16 ± 15.8 years (60.3% male,39.7% female). The most common drainage type was the two-ostium pattern bilaterally (right R2:78.3%; left L2:81.3%). On the right, subtype R2a was most frequent, whereas R3e and R4 were rare. On the left, L2a predominated, while L2c-L2d and L3 were uncommon. Non-classical drainage patterns were seen in 21.7% of right and 18.7% of left. The oval-type LA was the most prevalent morphology (76% overall). The two-ostium pattern was the most frequent drainage pattern on both the right and left sides in both oval and rectangular LA types. Morphometrically, the superior ostial diameter and its angle to the y-axis were greater on the left, whereas the distance and angle between superior and inferior ostia, and the intervenous saddle length, were greater on the right (p < 0.05). This study may improve the safety and accuracy of interventional procedures involving the LA by providing comprehensive morphoanatomical information on PV drainage patterns and LA morphology.
The infraorbital vein (IOV) is a small but clinically important component of the deep midfacial venous system, linking the infraorbital region, orbit, and infratemporal fossa. Despite its close association with the infraorbital nerve and artery, the IOV remains inconsistently described and systematically undercharacterized in the literature. This narrative review synthesizes current evidence on the embryology, anatomy, variations, and clinical relevance of the IOV to provide a clinically oriented framework. Embryologically, the IOV derives primarily from the primitive maxillary vein, with variable contributions from the orbitonasal venous channels, which explains its dual connections to the pterygoid venous plexus and the orbital venous system. Anatomically, it demonstrates considerable variability in presence, caliber, and spatial relationship within the infraorbital canal. The IOV may present as a single trunk, duplicated channels, or a plexiform network, with additional variation associated with accessory infraorbital foramina and emissary connections. Clinically, the IOV is relevant to orbital floor and zygomatic fracture repair, implant surgery, the spread of odontogenic infection, and esthetic procedures. Although often overlooked, the IOV represents a key component of a dynamic midface-orbit-skull base venous axis. Improved understanding of its anatomy and variation is essential for surgical planning and complication avoidance.
Owing to its superficial location and accessibility, the anatomical snuff box is increasingly used for minimally invasive and image-guided procedures. This study evaluated the morphology and variations of its key neurovascular structures. The study was conducted on 60 upper limbs (30 right and 30 left) from embalmed adult cadavers (15 males and 15 females; age range: 20-90 years). After exposure of superficial structures, detailed dissection of the anatomical snuff box was performed. The tendons forming its boundaries, along with the cephalic vein, superficial branch of the radial nerve, and radial artery, were assessed for their course, depth, diameter, and related morphometric parameters. The cephalic vein diameter ranged from 1.22 to 3.98 mm. The mean radial artery diameter was 2.65 ± 0.64 mm. Both cephalic vein and radial artery diameters were significantly greater in males than females. A tortuous radial artery course was observed in 73.3% of cases, while the remainder showed a relatively straight course. Radial artery tortuosity was significantly more common on the right side. A cephalic vein diameter of at least 2 mm, considered suitable for arteriovenous fistula creation, was observed in 88.8% of cases. The radial artery diameter exceeded 2.3 mm in 80% of specimens, supporting the feasibility of distal radial catheterization. Overall, the anatomical snuff box demonstrates favorable vascular dimensions for arteriovenous fistula creation and distal radial access. However, frequent radial artery tortuosity, particularly on the right side, should be considered during clinical interventions to minimize complications.
The quadratus lumborum (QL) is increasingly recognized as an anatomically important component of the posterior abdominal wall, yet its internal organization remains incompletely defined. This study aimed to characterize the layer-specific architecture of the QL and to quantitatively analyze the distribution of immunolabeled axonal components across its layers. Ten embalmed adult cadavers (mean age, 82.1 ± 9.9 years) were examined. Gross dissection and morphometric analysis were performed in eight cadavers (16 sides) to identify layer-specific organization and measure width and thickness at standardized anatomical landmarks; measurement reliability was assessed using intraclass correlation coefficients. Non-destructive three-dimensional reconstruction was performed in four phosphotungstic acid-enhanced block specimens using micro-computed tomography (micro-CT; voxel size, 72 μm). Histological and immunofluorescence analyses were performed in six sides using Masson's trichrome staining and double labeling for NF200 combined with choline acetyltransferase (ChAT), tyrosine hydroxylase (TH), or calcitonin gene-related peptide (CGRP). Marker-positive axons were quantified relative to NF200-positive axons. Gross dissection and micro-CT consistently demonstrated a three-layer organization of the QL, comprising the lumbocostal (LC), iliocostal (IC), and iliolumbar (IL) layers. Morphometrically, the LC was the smallest layer, the IC was the thickest, and the IL was the widest. Neural branches arose mainly from the ventral rami of T12-L4 and entered the muscle along its anterior and lateral aspects as neurovascular bundles. Intramuscular nerves were multifascicular, and mean axonal diameter was greatest in the IC (572.9 ± 41.8 μm) and IL (556.1 ± 38.4 μm) and smallest in the LC (276.9 ± 65.2 μm). Immunofluorescence analysis demonstrated layer-dependent differences in marker distribution: the IC showed the highest proportions of ChAT-positive (26.4%) and TH-positive (32.4%) axons, whereas the LC showed the highest proportion of CGRP-positive axons (24.5%). The IL showed lower proportions of ChAT-, TH-, and CGRP-positive axons and the highest residual NF200-positive fraction (39.7%). The quadratus lumborum is a reproducible multilayered structure with layer-specific morphometric and immunolabeled neural heterogeneity. These findings provide quantitative anatomical evidence of layer-specific structural and neuroanatomical heterogeneity within the quadratus lumborum.
Intravascular injection of colored molding materials used either alone or in combination with radiological contrast agents is increasingly used to enhance vascular visualization in cadaveric specimens for anatomical education and surgical training. Published studies remain scattered and show substantial methodological variation. This structured literature review summarizes current practices regarding specimen preparation, injection techniques, casting materials, contrast agents, and imaging modalities, with particular emphasis on their educational applications. A comprehensive literature search was conducted in PubMed, Scopus, Embase, Web of Science, and Google Scholar (1975-August 2025) using English, French, and German keywords. Reference lists were screened manually. After removal of duplicates, 702 records were screened, 145 full-text articles assessed, and 78 studies included. Included studies demonstrated variability in casting materials (primarily latex, with silicone, epoxy, and acrylic resins also reported), contrast agents (iodinated and barium-based compounds and lead oxide for CT, with gadolinium-based formulations predominantly used for MRI), perfusion pressures, flushing strategies, and specimen conditions (fresh-frozen, formalin-fixed, and Thiel-embalmed). However, methodological heterogeneity and inconsistent reporting limited direct comparison between approaches. The review nevertheless identifies representative reported technical protocols and highlights the main practical variables influencing protocol selection. Contrast-enhanced vascular casting provides valuable tools for anatomy education and surgical training by enabling direct correlation between radiological datasets and anatomical dissection. Beyond summarizing the literature, this review also offers practical protocol-selection guidance according to educational, research, and imaging objectives. As such, it may serve as a useful reference for teams implementing or refining these techniques in modern teaching environments.
The piriform aperture (PA) is a critical anatomical structure that forms the bony framework of the nasal inlet and influences nasal airway patency and support of the nasal base. This study aimed to present detailed morphometric and morphological data on the PA to contribute to the surgical anatomy of PA enlargement. Seventy adult crania (female, n = 34; male, n = 36) were included. Using standardized digital images, PA length, PA width, related craniometric distances, and planimetric area were measured with ImageJ software. PA morphology was classified into six types. PA length was 4.71 ± 0.67 cm in females and 5.54 ± 0.50 cm in males; PA width was 3.52 ± 0.39 cm in females and 3.80 ± 0.35 cm in males. PA area was 12.61 ± 2.77 cm2 in females and 15.99 ± 2.82 cm2 in males. PA length, width, width at the level of the infraorbital foramen, the nasion-anterior nasal spine distance, inter-infraorbital distance, rhinion-right/left infraorbital foramen distances, and PA area were significantly higher in males. Regarding morphological type distribution, the pear type was most frequent (42.86%), followed by inverted heart (21.43%), round (12.86%), teardrop (10%), and oval (8.6%). PA length in the round type was lower than in the pear/oval/teardrop types, whereas PA area in the oval type was higher than in the round type. PA morphometry demonstrates marked sexual dimorphism. In males, PA length was approximately 18% greater and PA area approximately 27% greater, reflecting the combined effect of increased length and width.
The unpaired visceral branches of the abdominal aorta (AA) are the coeliac artery (CA), superior mesenteric (SMA), and inferior mesenteric (IMA) arteries. In endovascular surgery and interventional radiology, it is crucial to understand the positions of these arteries and the distance between them and the aortic bifurcation (AB). This study aims to determine the vertebral positions of AA unpaired visceral branches, their distances from each other, and male-female differences in a large sample group using three-dimensional multi-detector computed tomography angiography (MDCTA) images. This study was performed in a retrospective manner using radio-anatomical planes and included 500 MDCTA images with an equal gender distribution. The most common CA, SMA, IMA, and AB vertebral positions were determined as T12-L1 disc, L1-middle, L3-middle, and L4-lower in females and males, respectively. The median values of CA-SMA, CA-IMA, CA-AB, SMA-IMA, SMA-AB, and IMA-AB distances were obtained as 1.55, 1.65, 8.62, 9.07, 12.09, 13.01, 7.04, 7.32; 10.47, 11.20; 3.48, 3.84 cm in females and males, respectively. The difference between females and males was statistically significant in each measurement (p < 0.05). Arteries were positioned closer to each other in females than in males. When radio navigators are unavailable, the positions of IMA and AB can be used by both genders to detect CA and SMA. We believe that this MDCTA-based study, conducted in a relatively large clinical imaging cohort, may provide descriptive anatomical reference data that could contribute to the understanding of vascular relationships in radiological and surgical contexts.
The superior and inferior gemellus muscles are small components of the deep gluteal region that contribute to lateral rotation and stabilization of the hip joint. Despite their functional importance, these muscles display notable morphological variability with potential clinical relevance. The aim of this study was to classify the morphological variations of the superior and inferior gemellus muscles observed during anatomical dissection. A total of 60 lower limbs (28 male lower limbs and 32 female lower limbs; 30 right and 30 left) from 30 cadavers of a Central European population, fixed in a 10% formalin solution, were examined. Upon dissection, the morphology of the superior and inferior gemellus muscles was assessed. Based on their course and the number of muscle bellies, four types of the superior gemellus muscle and three types of the inferior gemellus muscle were identified. The superior gemellus muscle was present in 86.7% of cases and the following types were distinguished: Type 1 (65%) was characterized by a single belly proximally attached to the external surface of the ischial spine and distally attached to the trochanteric fossa. Type 2 (10%) consisted of a double belly arising as a common muscular mass from the external surface of the ischial spine; the upper belly was distally fused with the piriformis tendon and attached to the tip of the greater trochanter, whereas the lower belly was distally attached to the trochanteric fossa of the femur. Type 3 (11.7%) presented as a single belly proximally attached to the external surface of the ischial spine and fusing with the piriformis muscle tendon. Their common tendon was distally attached to the tip of the greater trochanter. Type 4 (13.3%) was characterized by the absence of the superior gemellus muscle. The inferior gemellus muscle was present in 80% of cases and following types were identified: Type I (75%) consisted of a single belly proximally attached to the upper part of the ischial tuberosity and distally attached to the trochanteric fossa. Type II (5%) showed a double belly proximally attached to the upper part of the ischial tuberosity, fusing into a common muscular mass and distally attached to the trochanteric fossa. Type III (20%) - characterized by the absence of the inferior gemellus muscle. The superior and inferior gemellus muscles demonstrate considerable morphological variability. Knowledge of these variations is essential for clinicians involved in diagnostic imaging, surgical procedures, and the management of neurovascular compression syndromes.
Recent advances in intraoral ultrasonography (US) have enabled quantitative evaluation of periodontal tissues; however, limitations regarding applicable measurement sites and structural visualization remain. This study aimed to investigate the anatomical accuracy and measurement reproducibility of intraoral US imaging for soft and hard periodontal tissues, comprising buccal and lingual palatal surfaces and dental calculus. US images were captured from the gingival margin (GM), alveolar bone crest (ABC), and cementoenamel junction (CEJ) of 108 teeth from fixed human cadavers. These regions were sectioned and scanned to generate reference images. Three parameters were measured: (1) the distance between the ABC and GM, (2) the distance between the ABC and CEJ, and (3) the linear length of the dental calculus on the tooth surface. Three independent examiners performed all measurements twice for reliability analysis. US images clearly delineated the gingiva, CEJ, alveolar bone, and calculus based on their echogenic characteristics. No statistically significant differences were observed between the US and reference measurements (p > 0.05). Intraclass correlation coefficients ranged from 0.78 to 0.97 for intra-rater and 0.92 to 0.96 for inter-rater reliability. Bland-Altman analysis revealed 95% limits of agreement of - 0.27 to 0.94 mm for ABC-GM, - 0.28 to 1.12 mm for ABC-CEJ, and - 0.22 to 0.81 mm for calculus length. These findings confirm that intraoral US reliably represents anatomical structures with high fidelity. US is a valid, reproducible modality for evaluating ABC, GM, CEJ, and calculus across buccal and lingual surfaces, providing a standardized anatomical foundation.
Metacognition, defined as "thinking about thinking," is an essential skill that enables medical students to navigate the cognitive complexity of anatomy curricula. By fostering learners' abilities to monitor comprehension, recognise knowledge gaps, and strategically regulate their learning approaches, metacognition supports both academic achievement and lifelong learning. This narrative review provides a comprehensive overview of the role of metacognitive skills in anatomy education. It examines existing literature and educational interventions to provide insights into developing and applying these skills for students and educators. A targeted literature search was conducted across major electronic databases, including PubMed, Scopus, and ERIC. The search used a Boolean string combining terms related to metacognition with those for anatomy and health professions education. The review included a broad range of article types to synthesise diverse applications and theoretical underpinnings. Multiple studies show that explicit, integrated metacognitive interventions-such as structured training, reflective writing, and flipped classroom methodologies-are associated with improvements in metacognitive awareness. These approaches appear most effective when incorporated as ongoing, course-specific activities rather than as isolated sessions. Notably, while metacognitive knowledge improves readily, the development of self-regulatory learning behaviours requires sustained scaffolding and practice. The literature suggests metacognition as a crucial skill for academic success in anatomy and for a successful career as a health professional. An integrated pedagogical approach that combines strategies such as retrieval practice, peer teaching, and reflective writing appears essential. This approach fosters deep, lasting learning and empowers students to become self-directed, resilient learners who can continually adapt to new challenges throughout their careers.
Pain in the scapular region is a common musculoskeletal complaint, yet its anatomical basis often remains unclear. This study investigates the supraspinatus fascia as a potential contributor to shoulder pain, with particular emphasis on its surgical relevance. A total of 24 body donors were examined using dissection and histological analysis to characterize the fascia's morphology, topography, and neurovascular features. The supraspinatus fascia consistently demonstrated a distinct two-layered architecture. Both layers showed considerable interindividual variability, ranging from thin and translucent to dense and collagen rich. There is an interposed fat layer between the superficial and deep fascial layer suggesting a potential sliding interface. The fascia forms a tubular sheath around the supraspinatus muscle, attaching to the margins of the supraspinatus fossa as well as the superior transverse scapular ligament, clavicle, and coracoid process. The deep layer is continuous with the subacromial bursa and the posterior origin of the supraspinatus muscle. In contrast, the superficial layer integrates into surrounding fascial systems, including connections to the fasciae of the levator scapulae and rhomboid minor muscles. Histological analysis identified neurovascular bundles within and traversing both fascial layers. A subset of nerve fibres showed substance P immunoreactivity, supporting a nociceptive role of the supraspinatus fascia. The supraspinatus fascia is a complex structure rather than a passive wrapping. Its distinct two-layered architecture and substance P-positive innervation provide an anatomical basis for idiopathic scapular pain. Clinically, the deep layer's continuity with the subacromial bursa suggests that inadequate fascial release during subacromial decompression may lead to persistent symptoms. Finally, the superficial layer's connection to the "levator-rhomboid-minor-fascia" establishes a myofascial bridge for force transmission, suggesting that "shoulder pain" could be a manifestation of cervicoscapular fascial tension.
Extranumerary nasal conchae, including the supreme nasal concha (SupNC) and Zuckerkandl's concha (ZC), are uncommon variants relevant to endoscopic sinus and skull base surgery, yet their prevalence and morphometry remain poorly defined. No cadaveric study has simultaneously evaluated prevalence, detailed morphometry, and a data-driven SupNC classification using principal component analysis (PCA). This study determined SupNC prevalence in cadavers and proposed a clinically oriented classification integrating morphological and quantitative parameters. A cross-sectional cadaveric study analyzed 59 hemisections with preserved nasal conchae. Conchae were counted, and SupNCs classified according to Orhan and a new system. Morphometry was obtained using digital calipers and ImageJ. Of 59 hemisections, 37 (63%) had three conchae, 21 (35%) four, and 1 (2%) five. SupNC was present in 22/59 (37.3%) and ZC in 1/59 (1.7%), associated with SupNC. Significant differences were found between hemisections with and without extranumerary conchae in middle concha area (3.68 ± 1.07 vs. 4.45 ± 1.20 mm2), superior concha area (1.26 ± 0.40 vs. 0.94 ± 0.36 mm2), length (26.13 ± 4.19 vs. 21.93 ± 3.94 mm), and height (0.72 ± 0.24 vs. 0.45 ± 0.13 mm). Concha number strongly correlated negatively with nasal cavity height (r = -0.83). PCA identified two clusters: Straight (Type I) and Triangular (Type II) SupNCs. SupNC was relatively common, whereas ZC was rare. The proposed morphology- and morphometry-based classification may improve preoperative CT evaluation and intraoperative orientation.
The present study aimed to investigate the relationship between iliopsoas notch morphology and acetabular and coxal morphometric parameters in adult hip bones. Specifically, we sought to determine whether iliopsoas notch morphology is associated with overall pelvic dimensions or represents a localized, functionally adapted anatomical structure. A total of 184 adult dry hip bones (108 female, 76 male) were analyzed. Standard acetabular and coxal morphometric parameters were recorded, including acetabular diameters, depth, and pelvic dimensions. Iliopsoas notch width (INW), depth (IND), and morphology (curved, angular, irregular, straight) were assessed. Group comparisons and correlation analysis were performed to evaluate relationships between notch morphology and acetabular and coxal measurements. Most acetabular and coxal parameters demonstrated significant sexual dimorphism (p < 0.001), whereas acetabular notch width showed no sex difference (p = 0.85). The curved type was the predominant iliopsoas notch morphology (70.1%). Significant differences among notch types were observed only for transverse acetabular diameter, INW, and IND. Correlation analysis revealed strong internal relationships among acetabular parameters (r > 0.79), but only weak to moderate correlations between notch dimensions and acetabular or coxal measurements (r = 0.185-0.422). A strong correlation was observed between INW and IND (r = 0.75, p < 0.001). The iliopsoas notch demonstrates limited association with global acetabular and pelvic dimensions, suggesting greater influence from localized anatomical and biomechanical factors than from overall pelvic scaling. These findings have implications for understanding iliopsoas-related pathologies and optimizing acetabular component positioning in total hip arthroplasty.
The subtympanic sinus (STS) is a recess of the inferior retrotympanum of various morphology and depth. Its shape and dimensions may depend on the configuration of surrounding bony ridges and the degree of temporal bone pneumatization. Despite increasing interest in retrotympanic anatomy, quantitative radiological descriptions of STS variability in adults remain limited. Our aim was to describe the morphology, dimensions, and distribution of the subtympanic sinus in adults and to analyze its anatomical relationships with the facial nerve, the subcochlear canaliculus, and pneumatization of the temporal bone. Computed tomography (HRCT and CBCT) scans of 82 adults (164 temporal bones) without otologic disease were retrospectively analyzed. The STS was classified according to its extension relative to the mastoid segment of the facial nerve. Sinus depth and width were measured, and the presence of facial nerve-adjacent pneumatization, subcochlear canaliculus, and pneumatization within the vascular compartment of the petrous bone were assessed. Type A STS configuration was most prevalent (80.5%), followed by type B (16.5%) and type C (3.0%). STS depth increased progressively from type A to type C, with statistically significant differences among groups (p < 0.001), whereas sinus width did not differ significantly. A connection with the subcochlear canaliculus was present in 62.8% of temporal bones and was significantly associated with greater STS depth. Facial nerve-adjacent pneumatization was frequent (85.4%) and correlated with increased STS depth. The subtympanic sinus exhibits substantial morphological variability in adults, primarily expressed through differences in depth. Its configuration may reflect broader patterns of temporal bone pneumatization and may support the concept of an integrated retrotympanic and infracochlear anatomical system.
The auriculotemporal nerve (ATN), carrying both sensory and parasympathetic fibers, is a branch of the mandibular nerve (MN) and courses through the anatomically complex infratemporal fossa (ITF). Along its path, it maintains close proximity to the maxillary artery (MA) and middle meningeal artery (MMA). This study aimed to investigate the morphometry, formation patterns, and vascular relationships of the ATN in both adult cadavers and fetuses. Bilateral ITF dissections were performed on 15 adult cadavers (mean age: 76.07 ± 14.1 years) and 15 fetuses (mean gestational age: 23.87 ± 3.40 weeks). The number of roots forming the ATN, their morphometry, configurations, and vascular relationships were documented. A classification system was developed based on root number, fusion patterns, and spatial relation to the MA and MMA. Both adult and fetal specimens demonstrated various root and connection patterns. Up to five roots were observed in adults and up to four in fetuses. In both groups, the two-root configuration was the most common (60%). The first root passed lateral to the MMA in 87% of adults and 90% of fetuses, while the second root was medial in 81% and 79%, respectively. Understanding the anatomical variability of the ATN is essential for safe surgical navigation within the ITF. Dissection-based studies that illuminate such variations provide valuable guidance for clinical procedures involving this region.
The sigmoid sinus is a vital dural venous structure whose anatomical variability has direct implications for lateral skull base and otologic surgeries. Understanding the sinus's positional variations is considered important for minimizing surgical risks. This study aimed to evaluate the morphological classification of the sigmoid sinus using a surgical reference-based system and to assess its relationship with demographic variables. A retrospective analysis was conducted on high-resolution temporal bone CT scans of 241 patients (114 females [47.30%], 127 males [52.70%]) with an age range of 18-92 years (mean age: 47.95 ± 17.84). The morphology of the sigmoid sinus was classified into four types based on the system defined by Dong-Il Sun et al., using three anatomical reference lines. The width and depth of the sigmoid sinus were measured bilaterally and analyzed in relation to age and gender. Statistical analysis included paired tests for bilateral measurements, chi-square tests and ordinal logistic regression for associations with age and sex, and reliability assessment using Cohen's kappa and intraclass correlation coefficients. A total of 241 patients were included. Mean sigmoid sinus depth and width were 6.57 ± 1.73 mm and 14.55 ± 4.06 mm on the right, and 6.33 ± 1.52 mm and 15.18 ± 4.93 mm on the left, respectively. Left-sided width was significantly greater than the right (p < 0.05), whereas depth did not differ. Type 3 and Type 4 configurations predominated bilaterally; Type 1 was not observed. Age was significantly associated with left-sided sigmoid sinus type (p = 0.0048), with more medial configurations in older individuals. Ordinal regression showed decreasing odds of higher-type anatomy with increasing age (OR = 0.84 per decade). Gender was associated with left-sided type distribution but not independently predictive after adjustment. Inter- and intraobserver reliability was excellent. The positional morphology of the sigmoid sinus varies significantly with age and gender. The absence of Type 1 and predominance of high-risk configurations in younger individuals suggests the potential relevance of individualized preoperative assessment. This classification system may provide additional anatomical insight for radiologic evaluation; however, its direct impact on surgical decision-making requires further validation.