Accessory muscles of the anterior thoracic wall and axilla. Cadaveric, surgical and radiological incidence and clinical significance during breast and axillary surgery

Background: The present study aims to summarise the accessory muscles of the anterior thoracic wall and axilla that can be encountered during breast and axillary surgery and record their incidence and clinical significance. Moreover, the laterality of the atypical muscles is highlighted and possible gender dimorphism is referred. Accessory anterior thoracic wall muscles include: Langer’s axillary arch, sternalis muscle, chondrocoracoideus, chondroepitrochlearis, chondrofascialis, pectoralis minimus, pectoralis quartus and pectoralis intermedius. Materials and methods: The anatomical, surgical and radiological literaturę has been reviewed and an anatomical study on 48 Greek adult cadavers was performed. Results: Literature review revealed the existence of accessory muscles of the anterior thoracic wall and axilla that have a significant incidence that can be considered high and may, therefore, have clinical significance. For the most common of these muscles, which are axillary arch (Langer’s) and sternalis muscle, the cadaveric incidence is 10.30% and 7.67%, respectively. In the current cadaveric study, accessory thoracic wall muscles were identified in two cadavers; namely a bilateral sternalis muscle (incidence 2.08%) extending both to the anterior and posterior surface of the sternum and a left-sided chondrocoracoideus muscle (of Wood) (incidence 2.08%). Conclusions: Despite the fact that accessory anterior thoracic wall and axillary muscles are considered to be rare, it is evident that the incidence of at least some of them is high enough to encounter them in clinical practice. Thus, clinicians’ awareness of these anatomical structures is advisable

The position of the mental foramen in dentate and edentulous mandibles: clinical and surgical relevance

Background: The knowledge of the exact location of the mental foramen (MF) in dentate and edentulous mandibles is clinically important when constructing complete dentures, performing anaesthetic block of the lower-anterior teeth area and intervening in the MF nearby area. In edentulous mandibles, the bone resorption after teeth loss makes the mental nerve (MN) prone to damage due to the extreme location of the MF very close to the alveolar crest (AC). Chronic compression on the MN may result in pain in the area of MN distribution (ipsilateral face and cheek area) and numbness at the lower lip. The purpose of the current study is to evaluate the exact position of the MF, calculating the distances MF-superior border of the AC and MF-inferior border of the mandible (IBM) in dentate and edentulous mandibles. Materials and methods: One hundred and two (36 edentulous and 66 dentate) adult dry Greek mandibles were studied. Results: In 9 out of 36 edentulous mandibles (25%), the MF was found nearby the AC, while in 27 edentulous mandibles (75%), the MF was located at an average distance 6.4 mm from the AC and 12.6 mm from the IBM. In 38 out of 66 dentate mandibles (57.6%), the MF was located at an average distance 13.6 mm from the AC and 15.2 mm from the IBM. The dental status significantly affected (p = 0.001) the distances MF-AC and MF-IBM. Side symmetry was observed for both dentate and edentulous mandibles (p = 0.39 and p = 0.45). Conclusions: The MF is an important landmark and its location needs to be considered prior to dental implants placement in order to avoid the MN injury and related complications. The position of MF is altered in edentulous mandibles compared with the dentate ones. The MF is a symmetric structure in Greeks

Functional anatomy of the mandibular nerve: Consequences of nerve injury and entrapment

Various anatomic structures including bone, muscle, or fibrous bands may entrap and potentially compress branches of the mandibular nerve (MN). The infratemporal fossa is a common location for MN compression and one of the most difficult regions of the skull to access surgically. Other potential sites for entrapment of the MN and its branches include, a totally or partially ossified pterygospinous or pterygoalar ligament, a large lamina of the lateral plate of the pterygoid process, the medial fibers of the lower belly of the lateral pterygoid muscle and the inner fibers of the medial pterygoid muscle. The clinical consequences of MN entrapment are dependent upon which branches are compressed. Compression of the MN motor branches can lead to paresis or weakness in the innervated muscles, whereas compression of the sensory branches can provoke neuralgia or paresthesia. Compression of one of the major branches of the MN, the lingual nerve (LN), is associated with numbness, hypoesthesia, or even anesthesia of the tongue, loss of taste in the anterior two thirds of the tongue, anesthesia of the lingual gums, pain, and speech articulation disorders. The aim of this article is to review, the anatomy of the MN and its major branches with relation to their vulnerability to entrapment. Because the LN expresses an increased vulnerability to entrapment neuropathies as a result of its anatomical location, frequent variations, as well as from irregular osseous, fibrous, or muscular irregularities in the region of the infratemporal fossa, particular emphasis is placed on the LN. © 2010 Wiley-Liss, Inc

Neuroanatomy of the brachial plexus: Normal and variant anatomy of its formation

The brachial plexus is the complex network of nerves, extending from the neck to the axilla, which supplies motor, sensory, and sympathetic Wbers to the upper extremity. Typically, it is formed by the union of the ventral primary rami of the spinal nerves, C5-C8 & T1, the so-called "roots" of the brachial plexus. By examining the neural architecture of the brachial plexus, the most constant arrangement of nerve Wbers can be delineated, and the most predominate variations in the neural architecture deWned. A thorough understanding of the neuroanatomy of the brachial plexus, with an appreciation of the possible anatomic variations that may occur is necessary for eVective clinical practice. © Springer-Verlag 2009

Knowledge of the anatomy and physiology of the spleen throughout Antiquity and the Early Middle Ages

The evolution of knowledge regarding the anatomy and physiology of the spleen throughout Antiquity and the Early Middle Ages is described, and general perceptions about this organ during different eras along this time line are presented. The original words of great physicians from the period of time stretching from Ancient Egypt to the Avicennan era are quoted and discussed to demonstrate how knowledge of the spleen has evolved and to present the theories that dominated each era. Furthermore, theories about illnesses relating to the spleen are reported, which show how this organ was perceived—in terms of its function and anatomy—during each era. © 2015, Japanese Association of Anatomists

Mandibular nerve entrapment in the infratemporal fossa

The posterior trunk of the mandibular nerve (V3) comprises of three main branches. Various anatomic structures may entrap and potentially compress the mandibular nerve branches. A usual position of mandibular nerve (MN) compression is the infratemporal fossa (ITF) which is one of the most difficult regions of the skull base to access surgically. The anatomical positions of compression are: the incomplete or complete ossified pterygospinous (LPs) or pterygoalar (LPa) ligament, the large lamina of the lateral plate of the pterygoid process and the medial fibres of the lower belly of the lateral pterygoid (LPt). A contraction of the LPt, due to the connection between nerve and anatomic structures (soft and hard tissues), might lead to MN compression. Any variations of the course of the MN branches can be of practical significance to surgeons and neurologists who are dealing with this region, because of possibly significant complications. The entrapment of the MN motor branches can lead to paresis or weakness in the innervated muscle. Compression of the sensory branches can provoke neuralgia or paraesthesia. Lingual nerve (LN) compression causes numbness, hypoesthesia or even anaesthesia of the mucous of the tongue, anaesthesia and loss of taste in the anterior two-thirds of the tongue, anaesthesia of the lingual gums, as well as pain related to speech articulation disorders. Dentists should be very suspicious of possible signs of neurovascular compression in the region of the ITF. © 2010 Springer-Verlag