Non-specific low back pain and peripartum pelvic pain have aetiologies that may feature the sacroiliac region. This region possesses many potential pain-generating structures sharing common sensory innervation which makes clinical differentiation of pathoanatomy difficult. This anatomical study explores the relationship between the long posterior sacroiliac ligament (LPSL) and the lateral branches of the dorsal sacral nerve plexus. Twenty-five sides of the pelvis from 16 cadavers were studied, three for histological analysis and 22 for gross anatomical dissection. We found that the LPSL is penetrated by the lateral branches of the dorsal sacral rami of predominantly S2 (96%, 21/22) and S3 (100%, 22/22), variably of S4 (59%, 13/22) and rarely of S1 (4%, 1/22). Some of the penetrating lateral branches give off nerve fibres that disappear within the ligament. These findings provide an anatomical basis for the notion that the LPSL is a potential pain generator in the posterior sacroiliac region.
The stapedial artery is an embryonic artery which disappears during the tenth week in utero, in human species. During its short life, this artery shapes the stapes and transforms the middle meningeal artery from the internal carotid artery to a branch of the external carotid system. Nevertheless, a persistent stapedial artery is seen in 0.2-4.8 per thousand of human adults. This persistence is usually asymptomatic but can sometimes cause pulsatile tinnitus or conductive hearing loss. Despite the risk of facial palsy, hearing loss and even hemiplegia argued by several authors, some surgeons have succeeded in coagulation without side effects. Reviewing the literature, we seek to enlighten the actual knowledge about the persistent stapedial artery to evaluate the risk to coagulate it. Embryologic studies explain the four types of persistent stapedial arteries: the hyoido-stapedial artery, the pharyngo-stapedial artery, the pharyngo-hyo-stapedial artery and aberrant internal carotid with persistent stapedial artery. Phylogenetic studies show that the stapedial artery persists in adulthood in many vertebrates. Its disappearance is therefore either a random effect or an adaptative convergence. This adaptation could be partially linked to the negative allometry of the stapes. Practically, the risk to coagulate a stapedial artery seems limited thanks to anastomoses, for example with the stylomastoid artery. The risk of hemiplegia reported is in fact an extrapolation of variation in rats' embryos. A persistent stapedial artery can therefore reasonably be coagulated, with special attention to the facial nerve, because the facial canal is always dehiscent where the artery penetrates.
It is commonly believed that venous valves are not present in veins smaller than 2 mm in diameter. Venous valves, however, have been identified recently in small veins in several regions of the body. This study was undertaken to determine the size distribution of venous valves in the human lower limb micro-venous circulation. Vascular casts were made from six adult lower limbs and the sampled areas were viewed by scanning electron microscopy. In total, 2,376 valves were identified from 410 cm(3) of subcutaneous tissue. The vast majority (94%) of the valves were in veins less than 300 microm in luminal diameter, with 65% of the valves present in venous channels less than 100 microm in luminal diameter. The smallest valves identified were present in venous channels 18 microm in diameter. All valves were bicuspid and often associated with a tributary. Endothelial cells on the vein wall not associated with a valve were fusiform and arranged parallel to the long axis of the vessel, however, the endothelial cells on the luminal and valve sinus surfaces of the cusp were more polyhedral in shape and showed no obvious pattern of alignment. This study provides direct evidence to show that small superficial veins of the human lower limb do contain abundant venous valves and, for the first time, shows that the majority of these valves are present within venous channels less than 100 microm in luminal diameter.
Clinical anatomy is too often viewed as a discipline that reiterates the wisdom of the past, characterized more by description of what is known than by active investigation and critical analysis of hypotheses and ideas. Various misconceptions follow from an acceptance of this premise: the teaching of clinical anatomists is textbook based, there is no clinical anatomy research worthy of the name, and any research that does exist fails to utilize modern technology and does not stand comparison with serious biomedical research as found in cell and molecular biology. The aim of this paper is to challenge each of these contentions by reference to ongoing clinical research studies within this department. It is argued that all teaching (including that of clinical anatomy) should be research-informed and that the discipline of clinical anatomy should have at its base a vigorous research ethos driven by clinically related problems. In interacting with physicians, the role of the clinical anatomist should be to promulgate a questioning scientific spirit, with its willingness to test and challenge accepted anatomic dicta.
Conservation laryngeal surgery is an increasingly available alternative for the treatment of laryngeal cancer. Understanding anatomy of laryngeal lymph drainage is essential for clinicians to diagnose, grade and surgically manage the laryngeal cancer. Although the lymphatic drainage of the larynx has been extensively studied, few studies revealed the relationship of the lymphatic drainage between various parts of the larynx. The distribution of lymphatic vessels in the inferior surface of the vocal cord also remains unclear. The aim of this study was to investigate the communication of the lymphatic networks between the vocal cord, the supraglottic and subglottic parts of the larynx, paying special attention to the lymphatic drainage of the inferior surface of the vocal cord. Eighteen larynx specimens from 18 fresh fetal cadavers were manually injected with prassion blue solution into the mucosal or submucosal layer of the larynx in order to reveal the lymphatic vessels in the inner larynx. We found that a rich lymphatic network is present in the inferior surface of the vocal cord, and the lymphatic networks in the superior and inferior surfaces of the vocal cord appear as two different patterns. These findings provide an anatomical basis for the design of a partial or conservation laryngeal surgery, particularly when considering the precise resection margin.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.