An unusual relationship between the axillary artery and brachial plexus in a cross-breed dog cadaver: a proposal for revising the terminology for nerve loops.

In the left axilla of a formalin-embalmed adult female cross-breed dog, an unusual course of the axillary artery in relation to the brachial plexus was noted. A part of the axillary artery after the origin of the subscapular artery coursed through the loop formed by the contributions of the caudal pectoral and lateral thoracic nerves and then between the median and ulnar nerves. Thus, the common trunk for the latter two nerves was missing. Instead, in the proximal brachium, they communicated with each other in both directions. A communicating branch between the cranial and caudal pectoral nerves forming a nerve loop, ansa pectoralis lacked the axillary artery and was instead traversed by the subscapular artery. This is a variation in the relationship between the axillary artery and brachial plexus in the domestic dog and has not been reported in the literature yet. The axillary artery entrapped by the contributions of the caudal and lateral thoracic nerves may be considered as a risk factor for the neuroarterial compressions with non-specific signs and should be taken into account both in surgery and imaging.

Entrapment of subscapular artery by the splitting of radial nerve- putative clinical implications.

The third part of the axillary artery has an intimate relationship with the cords of the brachial plexus. The subscapular artery, the largest branch of the axillary artery, arises from its third part. The radial nerve is a branch of the posterior cord of the brachial plexus and its supplies the extensors of the arm, forearm and dorsum of the hand. During routine undergraduate dissection of the axilla of a formalin-fixed cadaver of about 70 years, the subscapular artery was found sandwiched between two divisions of the radial nerve. These anterior and posterior divisions of the radial nerve arose immediately after the formation of the radial nerve and encircled the subscapular artery and fused to form a single nerve subsequently. This variant anatomy can lead to conditions like subscapular entrapment causing ischemia of the scapular region and radial nerve compression causing weakness of the extensors of the upper limb. Injury to the nerve and vessel can occur while performing diagnostic and therapeutic procedures in the area. Knowledge of these variations provides a precautious approach by surgeons and other interventionists while working on this area.

The thoracoacromial trunk: a detailed analysis.

PURPOSE: The thoracoacromial trunk (TAT) originates from the second part of the axillary artery and curls around the superomedial border of the pectoralis minor, subsequently piercing the costocoracoid membrane. Knowledge about the location, morphology, and variations of the TAT and its branches is of great surgical importance due to its frequent use in various reconstructive flaps. METHODS: A retrospective study was conducted to establish anatomical variations, their prevalence, and morphometric data on TAT and its branches. The results of 55 consecutive patients who underwent neck and thoracic computed tomography angiography were analyzed. A qualitative evaluation of each TAT was performed. RESULTS: A total of 15 morphologically different TAT variants were initially established. The median length of the TAT was set at 7.74 mm (LQ 3.50; HQ 13.65). The median maximum diameter of the TAT was established at 4.19 mm (LQ 3.86; HQ 4.90). The median TAT ostial area was set to 13.97 mm (LQ 11.70; HQ 18.86). To create a heat map of the most frequent location of the TAT, measurements of the relating structures were made. CONCLUSION: In this study, the morphology and variations of the branching pattern of the TAT were presented, proposing a new classification system based on the four most commonly prevalent types. The prevalence of each branch arising directly from the TAT was also analyzed. It is hoped that the results of the present anatomical analysis can help to minimize potential complications when performing plastic or reconstructive procedures associated with TAT.

The Unusual High Origin Radial Artery in a Black Kenyan Population: A Cadaveric Study.

Background: The anatomy of the radial artery draws great interests among anatomists for its frequent involvement in variations. Equally, these variations have gained significant attention from clinicians because of the preference to use the radial artery for catheterization. The commonest of radial artery variations involve its site of origin. In published literature, data on this variations exist, but the prevalence of such variations in a Kenyan population has hitherto been unknown. Methods: Sixty-two upper limbs from 50 formalin-fixed cadavers were studied during dissection in the Department of Human Anatomy, University of Nairobi. Results: Fifty-four (87.1%) radial arteries arose within the cubital fossa, while eight (12.9%) had a high origin. Out of the eight high arteries, two (3.2%) branched off from the axillary artery, another two (3.2%) were branches of the proximal third of the brachial artery and four (6.5%) arose from the middle third of the brachial artery. The high origin radial arteries were more common on the right upper limbs (5 out of the 8 cases). Both axillary and brachial origins were seen bilaterally. Conclusion: The present study details important variations in the anatomy of the radial artery in a Kenyan population. With the radial artery being utilized during clinical, surgical and radiological interventions so frequently, an increased understanding and anticipation of such topographic variances is paramount.

Common arterial trunk for the branches of the third portion of the axillary artery: description of a case and its clinical application / Tronco arterial común para las ramas de la tercera porción de la arteria axilar: descripción de un caso y su aplicación clínica

SUMMARY: Variations of the axillary artery may have clinical implications capable of generating unexpected situations during surgical procedures of arterial reconstruction or vascular catheterization. The objective of this work was to report the finding of an anatomical variant of the axillary artery, which may have clinical and surgical implications. A descriptive study was conducted, in which a unilateral vascular variation found during a routine dissection in a right upper limb of a male cadaver was reported. From the second portion of the axillary artery originated a common arterial trunk that gave rise to the subscapular, anterior humeral circumflex, posterior humeral circumflex and deep brachial arteries. The third portion of the axillary artery did not emit branches. The common arterial trunk originated from the second portion, 62.64 mm from the beginning of the axillary artery. Its total length was 23.72 mm and its thickness was 6.1 mm. The caliber of the branches originating from the common arterial trunk was: subscapular artery 5.1 mm, anterior humeral circumflex of 1.66 mm, posterior humeral circumflex 3.18 mm and deep brachial 3.73 mm. The vascular variant detected altered the anatomical relationship of the axillary artery with the brachial plexus, generating a modification in the position of the fascicles and their terminal branches. Anatomical variations of the axillary artery are not infrequent, knowing them may be necessary during surgical procedures or anatomical dissections.

RESUMEN: Las variaciones de la arteria axilar pueden tener implicancias clínicas capaces de generar situaciones inesperadas durante procedimientos quirúrgicos de reconstrucción arterial o cateterismo vascular. El objetivo de este trabajo fue reportar el hallazgo de una variante anatómica de la arteria axilar, la cual puede tener implicancias clínicas y quirúrgicas. Se realizó un estudio de tipo descriptivo, en el cual se reportó una variación vascular unilateral encontrada durante una disección de rutina en un miembro superior derecho de un cadáver de sexo masculino. De la segunda porción de la arteria axilar se originó un tronco arterial común que daba origen a las arterias subescapular, circunfleja humeral anterior, circunfleja humeral posterior y braquial profunda. La tercera porción de la arteria axilar no emitía ramas. El tronco arterial común se originaba de la segunda porción, a 62,64 mm del inicio de la arteria axilar. Su longitud total era de 23,72 mm y su grosor de 6,1 mm. El calibre de las ramas originadas del tronco arterial común fue: arteria subescapular 5,1 mm, circunfleja humeral anterior de 1,66 mm, circunfleja humeral posterior 3,18 mm y braquial profunda 3,73 mm. La variante vascular detectada alteraba las relaciones anatómicas de la arteria axilar con el plexo braquial, generando una modificación en la posición de los fascículos y sus ramos terminales. Las variaciones anatómicas de la arteria axilar son frecuentes, conocerlas puede ser necesario durante procedimientos quirúrgicos o disecciones anatómicas.

Topography and Anatomical Variations of the Axillary Artery.

Knowledge of anatomical variations of the limb's main arteries is significant for the clinicians. Thus, this study is aimed at examining the branching pattern and anatomical variations of the axillary artery. We conducted research on 59 upper limbs of adult human donated cadavers. All axillary artery branches' origins were assessed, and the correlations between points of origins and variations of specific branches were evaluated. The average length of the axillary artery was found to be 11.22 cm, and this length was defined as reference line. Based on this reference line, the first, second, and third parts were 37.56%, 39%, and 30.05%, respectively. The STA was originated from 25.11%. The TAA and LTA were 42.67% and 54.82%, respectively. The SSA, ACHA, and PCHA were 64.72%, 83.89%, and 84.53%, respectively. The origin of LTA was correlated with that of SSA (R = 0.473, P < 0.05) and AHCA (R = 0.307, P < 0.05), respectively. And there was a positive correlation between AHCA and PHCA (R = 0.705, P < 0.05). The number of branches ranged from 3~6, and 9 types were shown. The most frequent branching pattern was common origin of the LTA and SSA (22/59). And AHCA and PHCA were originated together in 19 cases, and both patterns were combined in 12 cases. TTA and LTA branched together in 9 cases, and common trunk for the SSA, PHCA, and AHCA was found in 2 cases. According to this pattern, the origin of LTA and PCHA was significantly different. This information is particularly useful for surgeons and clinicians.

Neurovascular axillary variations: superficial brachial artery and single-corded brachial plexus.

Variants of the axillary artery and brachial plexus were found bilaterally in the axilla of an 86-year-old Asian female. On the left, the cadaver donor had a high bifurcation of the second part of the axillary artery, creating a superficial brachial artery. Meanwhile, the right axilla presented with root, trunk, and cord variations in the formation of the brachial plexus, the most interesting feature being a single, unified cord. Presented in this case report are the structural relationships of the variants with considerations regarding anatomy, embryology, prevalence, and clinical importance.

A macroscopic comparison study on main branches of arteria brachialis and arteria subscapularis in Southern Karaman and Hasak sheep breeds.

BACKGROUND: The Southern Karaman sheep, which is very fertile in terms of meat and milk production and is often preferred in livestock raising, is known as a domestic sheep breed. The Hasak sheep is a breed formed by the triple crossbreeding of the German Black-headed, Hampshire and Akkaraman breeds. Arterial feeding of the forelimb is provided by arteria axillaris, a continuation of arteria subclavia. In this study, it was aimed to examine the forelimb arteries in Southern Karaman and Hasak sheep breeds. MATERIALS AND METHODS: Totally, 8 Southern Karaman and 8 Hasak sheep were obtained from Konya Bahri Dagdas International Agricultural Institute. The sheep were anesthetised with xylazine and ketamine and extravasated by cutting the arteria carotis communis in the neck area of the sheep. The forelimbs of the sheep separated from the body were fixed in 10% formaldehyde solution and then dissections were made and the course and branching of the arteries were examined. RESULTS: It was determined that the arteria brachialis was divided into two main branches as distal arteria brachialis and proximal arteria subscapularis at the articulatio humeri level of the arteria axillary. Arteria mediana, which is a continuation of arteria brachialis, was also examined in different parts of antebrachium and ended by splitting into branches. CONCLUSIONS: According to the findings of the Southern Karaman and Hasak sheep breeds, it was determined that the forelimb arteries had some anatomical differences but were similar in structure to many sheep breeds.

Upper limb arterial pattern: clinical correlation and embryological perspective / Padrão arterial dos membros superiores: correlação clínica com perspectiva embriológica

Abstract Background Variations in the upper limb arterial pattern are commonplace and necessitate complete familiarity for successful surgical and interventional procedures. Variance in the vascular tree may involve any part of the axis artery of the upper limb, including the axillary artery and brachial artery or its branches, in the form of radial and ulnar arteries, which eventually supply the hand via anastomosing arches. Objectives To study the peculiarities of the arterial pattern of the upper limb and to correlate them with embryological development. Methods The entire arterial branching of forty-two upper limbs of formalin fixed adult human cadavers was examined during routine dissection for educational purposes, conducted over a 3-year period in the Department of Anatomy, Lady Hardinge Medical College, New Delhi. Results The study found: 1) One case in which a common trunk arose from the third part of the axillary artery, which immediately splayed into four branches (2.4%); 2) High division of the brachial artery into ulnar and radial arteries, in 3 cases (7.1%); 3) Pentafurcation of the brachial artery into ulnar, interosseus, radial, and radial recurrent arteries and a muscular twig to the brachioradialis in 1/42 cases (2.4%); 4) Incomplete Superficial Palmar arch in 3/42 cases (7.1%); and 5) Presence of a median artery in 2/42 case(4.8%) Conclusions This study observed and described the varied arterial patterns of the upper limb and identified the various anomalous patterns, supplementing the surgeon's armamentarium in various surgical procedures, thereby helping to prevent complications or failures of reconstructive surgeries, bypass angiography, and many similar procedures.

Resumo Contexto As variações no padrão arterial dos membros superiores são comuns e, assim, necessitam de total familiaridade para que os procedimentos cirúrgicos e de intervenção sejam bem-sucedidos. A variância na árvore vascular pode envolver qualquer parte da artéria axial dos membros superiores, incluindo a artéria axilar, a artéria braquial ou os seus ramos, na forma das artérias radial e ulnar, as quais, em algum momento, suprem as mãos através dos arcos anastomosados. Objetivos Avaliar as peculiaridades do padrão arterial dos membros superiores e correlacioná-las ao desenvolvimento embriológico. Métodos Foram examinados os ramos arteriais completos de 42 membros superiores de cadáveres adultos conservados em formalina, os quais eram rotineiramente dissecados para fins educacionais durante 3 anos no Departamento de Anatomia Lady Hardinge Medical College, Nova Delhi. Resultados O estudo apresentou cinco desfechos. 1. Foi constatado um caso em que um tronco comum surgiu da terceira parte da artéria axilar que imediatamente se disseminou em quatro ramos (2,4%). 2. Houve divisão maior da artéria braquial em artérias ulnar e radial em três casos (7,1%). 3. Em um caso, ocorreu pentafurcação da artéria braquial em ulnar, interóssea, radial, radial recorrente e de um galho muscular em braquiorradial (2,4%). 4. Foi constatado arco palmar superficial incompleto em três dos 42 casos (7,1%). 5. Foi observada a presença da artéria mediana em 2 dos 42 casos (4,8%). Conclusões Este estudo compreende o padrão arterial do membro superior e identifica os diversos padrões anômalos para agregar ao arsenal terapêutico de cirurgiões para diversos procedimentos cirúrgicos, com o objetivo de combater quaisquer complicações ou falhas de cirurgias reconstrutivas, de angiografias de cirurgias de revascularização e muitas outras.

The coracoid process is supplied by a direct branch of the 2nd part of the axillary artery permitting use of the coracoid as a vascularised bone flap, and improving it's viability in Latarjet or Bristow procedures.

BACKGROUND: A comprehensive understanding of the anatomy of the vascular supply of the coracoid is needed to ensure that the coracoid remains vascularised in order to optimize bone union during any coracoid transfer procedures. It is the purpose of this study to present an anatomical overview of the blood supply of the coracoid process, describing a previously unidentified vessel that arises directly from the axillary artery and nourishes the coracoid process, permitting the coracoid to be used as a free bone flap. METHODS: An anatomical study examining the blood supply to the coracoid process of the scapula was performed in 14 shoulders from 7 fresh frozen (unembalmed) adult cadavers. In addition, the vascular supply to the coracoid was studied in 22 shoulders in patients during operations around the anterior shoulder. RESULTS: In all the cadaveric shoulders studied there was a single consistent direct branch of the second part of the axillary artery that supplied the distal 2-3 cm of the coracoid process with a corresponding vein. The mean pedicle length for the artery was 4.46 cm (range 3.1-5.6 cm). This artery originated from the axillary artery from the antero-lateral position in 6, lateral position in 3 and posterolateral position in 5 shoulders. The mean pedicle length for the vein was 5.8 cm (range 4.5-7.8 cm). The vein joined directly to the axillary vein in 3 shoulders and via another tributary (parallel to the axillary vein) in 9 shoulders. The diameter of the artery and vein averaged 1-1.5 mm. The clinical study confirmed the findings of the cadaveric study. CONCLUSION: Our anatomical cadaveric and clinical studies demonstrate the presence of a previously unidentified direct arterial branch from the second part of the axillary artery supplying the anterior 2-3 cm of the coracoid process of the scapula. This consistent vessel and accompanying vein should be preserved for any surgical procedure that involves transfer of the coracoid process, such as the Laterjet and Bristow procedures for shoulder dislocation and can be used for free transfer of the coracoid where a small vascularised bone flap may be required.

The axillary vein and its tributaries are not in the mirror image of the axillary artery and its branches.

INTRODUCTION: The axillary and cephalic veins are used for various clinical purposes but their anatomy is not fully understood. Increased knowledge and information about them as well as superficial veins in the upper arm would be useful. OBJECTIVE: The aim of this study is to contribute to the literature regarding the anatomy of the venous drainage of the upper extremity. METHODS: The veins of forty upper extremities from twenty one adult cadavers were injected and their axillary regions dissected. The course and pattern of drainage of the venous tributaries in the axillary region were identified and recorded. RESULTS: The basilic, brachial, subscapular, lateral thoracic and superior thoracic veins drained mainly into the axillary vein, in common with most textbook descriptions. However, the thoracoacromial veins were observed to drain into the cephalic vein in 70.0% of upper limbs. In addition, a venous channel connecting the distal part and proximal part of the axilla was found along the posterolateral wall of the axilla in 77.5% of the upper limbs. In 95.0% of upper limbs, we discovered a superficial vein which ran from the axillary base and drained directly into the axillary vein. CONCLUSION: The veins from the inferomedial part of the axilla drain into the axillary vein, whereas the veins from the superolateral part of the axilla drain into the cephalic vein. The venous drainage of the axilla is variable and in common with venous drainage elsewhere, does not necessarily follow the pattern of the arterial supply.

Prevalence of Perforated Graft in Underlay and Pop-in Technique Myringoplasty.

INTRODUCTION: The radial artery is commonly originated from the brachial artery in the cubital fossa at the level of the neck of the radius. It is the artery of choice for coronary artery angiography, percutaneous coronary artery intervention, cannulation, and others. Radial artery anomalies like high origin, tortuosity, and accessory branches are associated with the failure of such procedures. The main objective of this study is to study the variation in origin and course of the radial artery in cadavers. METHODS: A descriptive cross-sectional study was conducted in 27 formalin-fixed adult human cadavers in the Department of Anatomy, KIST Medical College and Teaching Hospital, Lalitpur, Nepal, from 2075/4/2 to 2076/4/2. Ethical approval was taken on date 02/04/2075 (IRC No. 2074/75/38). Altogether, 53 specimens were enrolled in the study by convenience sampling method. Point estimate at 95% Confidence Interval was done for binary data along with frequency and proportion. The data was analyzed by and Statistical Package for the Social Sciences version 20. RESULTS: Out of of 53 upper limbs, forty-six (86.79%) specimens, the origin of the radial artery was observed to be normal in the cubital fossa, 34.5±6.31mm below the level of the intercondylar line of the humerus with the superficial course. In seven (13.21%) specimens, the radial artery showed variation in the origin. Among them, variations in origin were found to be from sites like the axilla, upper-middle, and lower part of the arm. One cadaver showed a tortuous radial artery bilaterally. CONCLUSIONS: This study concludes that most of the radial artery originates in the cubital fossa from the brachial artery with few variations.

Proper Choice of Vessels for Supermicrosurgery Training: An Experimental Animal study.

BACKGROUND: Reconstruction using supermicrosurgery, a technique of microneurovascular anastomosis for smaller vessels (< 0.8 mm), has become popular. Experimental animal studies for supermicrosurgery training have been reported; however, there have been few studies performed according to vessel diameter and pedicle length. In this study, the external diameters of four vessels (femoral, superficial epigastric, axillary, and common thoracic) and pedicle length of two flaps (superficial epigastric and common thoracic-long thoracic) were measured. METHODS: The inguinal and pectoral regions of Sprague-Dawley rats (n = 19) were dissected anatomically, and the external diameters of the four vessels were measured (right and left, artery and vein measured separately). After elevating the superficial epigastric and common thoracic-long thoracic flaps, the pedicle length of the flaps was also measured. RESULTS: Among the 16 vessels examined, the external diameters of 11 and 5 vessels were above and below 0.8 mm, respectively. The external diameters of the superficial epigastric vessel and common thoracic vessel (both arteries and veins) were below 0.8 mm. The external diameters of the femoral and axillary vessels (veins) were above 0.8 mm. The length of the common thoracic-long thoracic pedicle was approximately10 mm longer than that of the superficial epigastric pedicle. CONCLUSIONS: The external diameters of the superficial epigastric vessel and common thoracic vessel are small enough for supermicrosurgery training. The pedicle lengths of both the superficial epigastric and common thoracic-long thoracic flaps are sufficient to perform free flap experiments. Supermicrosurgical free flaps using these two vessels and a study of the physiology and pharmacology of the flaps will likely be possible in the future.

The zonal pattern of arterial supply to the brachial plexus and its clinical significance.

PURPOSE: To provide the anatomical basis of blood supply of brachial plexus for the clinical microsurgical treatment of brachial plexus injury. METHODS: Thirteen adult anticorrosive cadaveric specimens (8 males, 5 females) were dissected in this study. 3 fresh cases (2 males, 1 female) were used to observe the zonal pattern of arteries supplying brachial plexus, and 10 cases (6 males, 4 females) were used to observe the source and distribution of the brachial plexus arteries under microscope. RESULTS: The brachial plexus is supplied by branches of the subclavian-axillary axis (SAA), and these branches anastomose each other. According to distribution feature, blood supply of the brachial plexus could be divided into three zones. The first zone was from the nerve roots of intervertebral foramina to its proximal trunks, which was supplied by the vertebral artery and the deep cervical artery. The second zone was from the distal nerve trunks of the brachial plexus, encompassing the divisions to its proximal cords, which was supplied by direct branches of the subclavian artery or by branches originating from the dorsal scapular artery. The third zone was from the distal portion of the cords to terminal branches of the brachial plexus, which was supplied by direct branches of the axillary artery. CONCLUSIONS: The zonal pattern of arterial supply to the brachial plexus is a systematic and comprehensive modality to improve anatomical basis for the clinical microsurgical treatment for brachial plexus injury.

Anatomic landmarks for arthroscopic suprapectoral biceps tenodesis: a cadaveric study.

BACKGROUND: Biceps tenodesis reduces the incidence of Popeye deformity occurring with tenotomy, but pain may occur with tenodesis superior to or within the bicipital groove. Arthroscopic suprapectoral tenodesis is an attractive alternative. The purpose of this study was to establish landmarks for arthroscopic suprapectoral tenodesis and determine the appropriate fixation point to optimize muscle tension. METHODS: Twelve fresh cadaveric shoulders were dissected. Urethane polymer was injected into the axillary artery. The position of the anterior branch of the axillary nerve was marked. The transverse humeral ligament was split, exposing the biceps (long head of the biceps [LHB]) from its origin to the pectoralis major tendon (PMT). The intra-articular portion was released. Measurements were taken from the proximal tendon to described landmarks. RESULTS: The mean length of the intra-articular LHB was 2.53 cm (range, 1.72-3.55 cm). The mean distance from the LHB origin to the inferior lesser tuberosity (LT) was 5.58 cm (range, 4.02-6.87 cm), and that to the superior border of the PMT was 8.46 cm (range, 6.46-10.78 cm). The suprapectoral tenodesis zone (inferior LT to superior PMT) was 2.96 cm (range, 1.54-4.40 cm). In all specimens, a branch of the anterior humeral circumflex arose medial to the LHB and distal to the LT and crossed the suprapectoral zone from medial to lateral at 1.49 ± 0.42 cm proximal to the PMT, approximately at the level of the axillary nerve. The musculocutaneous nerve was on average 3.06 cm (range, 1.86-3.76 cm) from the tenodesis zone. CONCLUSION: A branch of the anterior humeral circumflex is a reliable landmark for identifying the mid-suprapectoral zone. The distance from the proximal LHB tendon to this crossing vessel averaged 6.32 cm in female specimens and 8.28 cm in male specimens. These findings allow appropriate tensioning of the LHB during arthroscopic suprapectoral tenodesis.

Variations in the origin and course of the suprascapular artery: case report and literature review / Variações na origem e percurso da artéria supraescapular: relato de caso e revisão da literatura

Abstract The suprascapular artery is normally a branch of the thyrocervical trunk of the subclavian artery. During dissection of the left upper limb of a female cadaver, aged 70 years and fixed in 10% formalin solution, the suprascapular artery was observed aberrantly arising from the first part of the axillary artery. Later, it coursed obliquely behind the clavicle bone and brachial plexus to reach the suprascapular notch, where it was accompanied by the suprascapular nerve. Then, both suprascapular nerve and artery anomalously traversed beneath the transverse scapular ligament. It then irrigated the supraspinatus muscles and took part in the anastomosis around the scapula. On the contralateral side there was no abnormality. Variations in the origin and course of suprascapular artery are of immense value to orthopedic and vascular surgeons, angiographists, and anatomists.

Resumo A artéria supraescapular normalmente se apresenta como um ramo do tronco tireocervical da artéria subclávia. Durante a dissecção do membro superior esquerdo de um cadáver do sexo feminino com idade de 70 anos fixado em solução de formol 10%, observou-se que a artéria supraescapular tinha origem aberrante na primeira parte da artéria axilar. Mais adiante, a artéria cursava obliquamente por trás da clavícula e plexo braquial até atingir a incisura supraescapular, onde era acompanhada pelo nervo supraescapular. A partir daí, tanto o nervo quanto a artéria supraescapulares atravessavam de forma anômala por baixo do ligamento transverso da escápula. Neste ponto, irrigavam os músculos supraespinhosos e faziam parte da anastomose em torno da escápula. No lado contralateral, não havia anormalidade. Variações na origem e percurso da artéria supraescapular são de grande valor para cirurgiões ortopédicos e vasculares, angiografistas e anatomistas.

Evaluation of the relationship between the topographical anatomy in the axillary region of the brachial plexus and the body mass index.

To investigate the topographic anatomy of the median, musculocutaneous, radial and ulnar nerves with respect to the axillary artery and to seek whether these configurations are associated with baseline descriptive data including age, gender, and body-mass index. This cross-sectional trial was carried out on 199 patients (85 women, 114 men; average age: 46.78 ± 15.45 years) in the department of anaesthesiology and reanimation of a tertiary care center. Topographic anatomy of the median, musculocutaneous, radial and ulnar nerves was assessed with ultrasonography. Localization of these nerves with respect to the axillary artery was marked on the map demonstrating 16 zones around the axillary artery. Frequencies of localizations of every nerve in these zones were recorded, and the correlation of these locations with descriptive data including age, gender and BMI was investigated. There was no difference between women and men for the distribution of the median (p = 0.74), ulnar (p = 0.35) and radial (p = 0.64) nerves. However, the musculocutaneous nerve was more commonly located in Zone A13 in men compared to women (p = 0.02). The localization of the median (p = 0.85), ulnar (p = 0.27) and radial (p = 0.88) nerves did not differ remarkably between patients with BMI < 25 kg/m2 and patients with BMI ≥ 25 kg/m2. Notably, the musculocutaneous nerve was more often determined in Zone A10 in cases with BMI ≥ 25 kg/m2 (p = 0.001). Our results imply that the alignment of the musculocutaneous nerve may vary in men and overweight people. This fact must be considered by the anaesthetist before planning the axillary block of brachial plexus. All these informations may enlighten the planning stages of the brachial plexus blockade.

A study of anatomical variations of median nerve formation and its relation to the arteries in the axilla and arm / Estudio de las variaciones anatómicas en la formación del nervio mediano y su relación con las arterias de la axila y el brazo

Variations of the peripheral nerve formation, communication and distribution are clinically important because such knowledge can be used for proper planning of surgeries and evaluating effects of nerve injuries and clinical imaging. Median nerve is known to have several such variations. However studies done on median nerve in Sri Lankan subjects are spars. The objective of this study was to find out anatomical variations of the median nerve with regards to its variations in roots and relations to the arteries in the axilla and arm. The study was done using 98 upper limbs of 49 formalin fixed cadavers. They were dissected and anatomy of the median nerve formations was studied focusing its variations of the roots and relation to the arteries. Anatomical variations of MN formation were observed in 33 (33.67 %) upper limbs with 4 bilateral and 25 unilateral variations. These variations were classified broadly in to two groups, variations of roots (15.3 %) and variation of arterial relations (18.37 %). There were three types of numerical variations (9.18 %) and three types of morphological variations (6.12 %) of roots. The median nerve was found to form in relation to the 2nd part of the axillary artery in 6.12 %, abnormal relation to the 3rd part of the axillary artery in 2.04 %, normal relation to the 3rd part of the axillary artery in 81.63 %, and brachial artery in 10.2 % of the specimens. The current study highlights the presence of different anatomical variations at median nerve formation with regards to its roots and arterial relations and describes three rare forms of anomalies which were not found on literature survey.

Las variaciones de la comunicación, formación y distribución del nervio periférico son clínicamente importantes para la planificación adecuada de las cirugías y para evaluar los efectos de las lesiones nerviosas y la imagen clínica. En el nervio mediano se han observado varias de estas variaciones. Sin embargo, son escasos los estudios realizados del nervio mediano en sujetos de Sri Lanka. El objetivo de este estudio fue conocer las variaciones anatómicas del nervio mediano con respecto a sus raíces y las relaciones con las arterias axilar y braquial. El estudio se realizó utilizando 98 miembros superiores de 49 cadáveres fijados con formalina. Se disecó y se estudió la anatomía de las formaciones de los nervios medianos, enfocando sus variaciones a nivel de las raíces y las relaciones con las arterias. Se observaron variaciones anatómicas de la formación de nervio mediano en 33 miembros superiores (33,67 %) con 4 variaciones bilaterales y 25 unilaterales. Estas variaciones se clasificaron ampliamente en dos grupos, variaciones de raíces (15,3 %) y variación de las relaciones arteriales (18,37 %). Existen tres tipos de variaciones numéricas (9,18 %) y tres tipos de variaciones morfológicas (6,12 %) de las raíces. Se encontró que el nervio mediano se formaba en relación con la 2 parte de la arteria axilar en el 6,12 %, relación anormal con la 3 parte de la arteria axilar en 2,04 %, relación normal con la 3 parte de la arteria axilar en el 81 ,63 % y braquial en el 10,2 % de los especímenes. El presente estudio señala la presencia de diferentes variaciones anatómicas en la formación del nervio mediano con respecto a sus raíces y relaciones arteriales y describe tres anomalías raras que no se encontraron en la investigación bibliográfica.

The Branching Pattern of the Brachiocephalic Trunk in the Donkey (Equus asinus).

Donkeys are a member of the horse family (Equidae) and share a common ancestor. However, in morphological terms, donkeys and horses are regarded as two separate subgenus. Given variations in the branching pattern of the brachiocephalic trunk (BCT) in different species of animals and the use of donkeys in anatomy courses at colleges of veterinary medicine, we conducted this study in order to investigate the branching patterns of BCT and to describe detailed morphological information regarding donkeys. Seventeen mature donkeys were examined following euthanasia by exsanguination from the common carotid artery under general anaesthesia. Thirteen donkeys were embalmed and injected with coloured latex from BCT origin for better visualization of vessels. Four other donkeys were freshly studied without the embalming procedure. In all cases, the BCT was the only branch of the aortic arch and branched into the left subclavian (LSb) artery, the right costocervical trunk, the right subclavian (RSb) artery and the bicarotid trunk. The main branching pattern of the RSb was the costocervical trunk, the vertebral artery, the internal thoracic artery and the superficial cervical artery. The deep cervical artery branched from the costocervical trunk. The major branching pattern of the LSb was the vertebral artery, the internal thoracic artery and the superficial cervical artery. In donkeys, the external thoracic artery branches from the internal thoracic artery. Results obtained from this study indicate that BCT branching in donkeys has some similarities and differences as compared to that in horses and in the Caspian miniature horse.

Accessory subscapularis muscle - A forgotten variation?

The quadrangular space is a space in the axilla bounded by the inferior margin of the teres minor muscle, the superior margin of the teres major muscle, the lateral margin of the long head of the triceps brachii muscle and the surgical neck of the humerus, medially. The axillary nerve (C5-C6) and the posterior circumflex humeral artery and veins pass through this space in order to supply their territories. The subscapularis muscle is situated into the scapular fossa and inserts itself into the lesser tubercle of the humerus, thus helping stabilize the shoulder joint. A supernumerary muscle known as accessory subscapularis muscle originates from the anterior surface of the muscle and usually inserts itself into the shoulder joint. It is a rare variation with few reports of its existence and incidence. We present a case of the accessory subscapularis muscle in a male cadaver fixated with a 10% formalin solution. The muscle passed anteriorly to the axillary nerve, thus, predisposing an individual to quadrangular space compression syndrome. We perform a review of the literature and address its clinical, anthropological and anatomical significance.