Anatomical Science International最新文献

The skull base serves as structural support for the brain and as a conduit for neurovasculature. Traditional morphometric methods have intrinsic limitations which make wholistic assessment of this anatomy challenging. Here we applied geometric morphometric techniques to address the problems associated with traditional morphometric strategies for evaluating skeletal and soft tissue components of the skull base. A Microscribe® i+ 3-D digitizer was used to register the location of 20 3-D skeletal and neural landmarks on the skull base of 80 anatomic body donors (mean age 83.0 ± 10.1 years). Linear measurements of neurocranial dimensions were collected with traditional methods. A principal component analysis (PCA) was applied to Procrustes aligned coordinates of the 3-D data. The first principal component accounted for 34.24% of the variation and was associated with changes in clival width and sella turcica length. Shape changes associated with PC1 scores correlated with configuration size (centroid size) (R² = .532, p < .001). PC2 (12.85%) was associated with isolated changes in clival width driven by the jugular tubercles. Results related to PC3 (11.10%) showed variation in skull base flattening. PC2 and PC3 results were correlated with neurocranial length and measurements of cranial width. Skull base size emerged as a principal driver of skull base shape. The jugular tubercle and surrounding foramina represented another locale of variation. Finally, our results support the idea that a wide range of non-pathologic skull base flattening may exist, as this shape axis was a major contributor to the variation seen in the sample.

This study aimed to present a new method to predict an area with no Radial Nerve (RN) distribution (safe zone of the RN) in the middle and lower of the upper limb. The RN(60 in total) were dissected from 30 adult cadavers (20 males and 10 females). Acromial Angle, Olecranon, and Lateral Epicondyle of Humerus were selected as reference points. The linear projection of the RN on Acromial Angle-Olecranon and Acromial Angle-Lateral Epicondyle of Humerus were marked as 'Intersection Point A' and 'Intersection Point B'. The lengths of Acromial Angle-Lateral Epicondyle of Humerus, Acromial Angle-Olecranon, Intersection Point A-Olecranon, Intersection Point B-Lateral Epicondyle of Humerus were measured. In this connection, the safe zone of the RN on the middle and lower Humerus was illustrated using Python3.11 and PyCharm2023.3.4. The mean position of Intersection Point A was located at (59.9 ± 6.2)% of the total length of Acromial Angle-Olecranon distally and the mean position of Intersection Point B was at (42.9 ± 6.6)% of the Acromial Angle-Lateral Epicondyle of Humerus. We identified absolute safe zone (with no RN distribution) on the middle and lower part of the Humerus enclosed by Olecranon, Lateral Epicondyle of Humerus, the 42.50% point of Acromial Angle-Olecranon distally, and the 28.10% point of Acromial Angle-Lateral Epicondyle of Humerus distally. In addition, relative safe zone (with less than 5% probability of the RN distribution) enclosed by Olecranon, Lateral Epicondyle of Humerus, the 50.33% point of Acromial Angle-Olecranon distally, the 32.98% point of Acromial Angle-Lateral Epicondyle of Humerus distally. Data in this study can help us locate the RN with body surface markers during Humerus fracture fixation.

This study addresses a longstanding discrepancy between the observed course of the superior epigastric artery (SEA) in human donors and its depiction in many German-language anatomy textbooks. While the SEA typically runs ventral to the diaphragm, several textbooks inaccurately describe it as passing through the sternocostal triangle (Larrey's fissure). Anatomical dissections were performed on 40 formalin-fixed human donors at the Medical University of Vienna. The thoracic and abdominal walls were systematically dissected, and the course of the SEA was documented. Additionally, historical literature from Dominique Larrey to present-day sources was analyzed to trace the origin and persistence of the inaccurate anatomical description. In all specimens, the SEA remained ventral to the pleural and peritoneal cavities and did not traverse Larrey's space. The misinterpretation appears to have originated in the 19th century through a chain of misreadings that began with Joseph Hyrtl and was later codified by Friedrich Merkel and was subsequently perpetuated in various German-language anatomical references. This study challenges the traditional textbook depiction of the SEA's pathway through Larrey's space and suggests that historical anatomical literature should be revised to reflect accurate topographical relationships.

The long head of the biceps femoris (BFlh) is among the most frequently injured components of the hamstring complex, particularly at the myotendinous junctions (MTJs). Despite its clinical relevance, the gross morphology of the BFlh-including its tendon structure and anatomic variability-remains insufficiently characterized. This study aimed to provide a detailed anatomic and morphometric analysis of the BFlh, focusing on the proximal and distal tendons and their integration with surrounding muscle fibers. Thirty-five formalin-fixed male cadavers were dissected via a posterior longitudinal approach. Tendons were subdivided into free, intermediate, and intramuscular portions. Morphometric data were collected using digital calipers and flexible measuring tape, and correlation analyses were performed using appropriate statistical methods. The total muscle length ranged from 42.0 to 50.0 cm. The tendons showed consistent segmentation, with significant correlations between tendon lengths and limb dimensions, as well as between MTJp and MTJd lengths. The thinner, more variable intramuscular segments may contribute to increased injury susceptibility. These findings support a standardized understanding of MTJ architecture and may enhance injury classification, diagnosis, and rehabilitation strategies.

The vinculum breve, a structure connected to the flexor digitorum superficialis tendon, located near the volar plate of the proximal interphalangeal joint. It has traditionally been regarded as a conduit for vascular supply to the tendon and its sheath. However, the detailed morphology of the vinculum breve and its relationship to the volar plate have not been fully elucidated. In this study, we examined the vinculum breve at the proximal interphalangeal joints from the index to little fingers of 20 cadavers (160 fingers in total). Two morphological types of the vinculum breve were identified: cord-like (59.4%) and membranous (40.6%). The membranous vinculum breve attached to the proximal interphalangeal joint tended to be denser proximally than distally. A high proportion (82.5%) of the vinculum breve was found to be attached to the volar plate. Cord-like vinculum breve was significantly more common in the index and middle fingers, where it attached to portions of the volar plate. In contrast, membranous vinculum breve was significantly more frequent in the little finger, often covering a large portion of the volar plate. These findings suggest that during flexion of the proximal interphalangeal joint, the vinculum breve contributes to the proximal sliding of the volar plate in coordination with the flexor digitorum superficialis tendon.

The biceps brachii muscle is known for its anatomical variability, particularly regarding the presence of additional heads, most commonly arising proximally as third, fourth, or even fifth heads. Distal variations, however, are rarely described in the literature. In this case report, we describe a rare bilateral finding of an accessory muscle belly originating from the short head of the biceps brachii. This accessory belly gives rise to a distinct tendon and inserts distally to the main biceps tendon. Recognition of this unusual anatomical arrangement in the cubital fossa is crucial to avoid misdiagnosis, guide appropriate treatment planning, and prevent iatrogenic injury during surgical procedures involving the elbow or forearm.

White matter injury is a cerebral pathology marked by the loss of oligodendrocytes and the resultant demyelination. Various mechanisms induce white matter injury, including ischemic stroke and multiple sclerosis. Oligodendrocytes regenerate white matter in the central nervous system in a process called remyelination, ensheathing demyelinated axons with new myelin. While failures of remyelination can be observed in progressive multiple sclerosis and after ischemic stroke, the mechanisms of impaired white matter regeneration remain unclear. In this review, we primarily focus on our recent work while summarizing studies reporting on mouse models of internal capsule demyelination and discuss inhibitory factors affecting white matter regeneration. In addition, we provide recent findings on the role of type I collagen as an inhibitory molecule of remyelination in white matter lesions.