Revista Română de Anatomie funcţională şi clinică, macro- şi microscopică şi de Antropologie Vol. XVII – Nr. 4 – 2018 CLINICAL ANATOMY VARiation OF THE ORIGin OF THE LatERAL THORacic ARTERY. CASE REPORT Tamás-Csaba Sipos2, Lóránd Dénes1*, Klara Brînzaniuc1, Annamária Szántó1, Zoltán Pávai1, Zsuzsánna Pap1 University of Medicine, Pharmacy, Sciences and Technology of Tîrgu-Mureş 1. Department of Anatomy and Embryology 2. Student, GM 6th year VARIATION OF THE ORIGIN OF THE LATERAL THORACIC ARTERY. Case RePORT (Abstract): Introduction: Anatomical variations of the origin of axillary artery branches are quite common. The most frequent variations are common trunks or emergence from a different segment than the classical description. Material and method: A formalin fixed male human cadaver has been dissected during teaching classes for medical students at the Anatomy and Embryology De- partment of UMFST Târgu Mureş. We observed a pattern of origins of the axillary artery branch- es different from the classical description. Results: The second part of the axillary artery provides the superior thoracic artery and the thoraco-acromial artery from its anterior surface, while the subscapular artery separates from its posterior surface. The lateral thoracic artery is a branch of the subscapular artery. The anterior and posterior circumflex humeral arteries come from the third part of the axillary artery, which corresponds to the classical description. Conclusions: Published studies report multiple variations regarding the origin of the axillary artery branches. Most com- monly, the lateral thoracic artery originates from the subscapular artery, which is the case in our study as well. Key-words: LATERAL THORACIC ARTERY, vaRIATION, SUBSCAPULAR ARTERY INTRODUCTION provides six branches, which are grouped ac- Arterial supply to the thoraco-scapulo-hu- cording to its parts: the first part gives off the meral area is provided by the branches of the superior thoracic artery, the second part pro- axillary artery. The axillary artery continues vides the thoraco-acromial artery and lateral the subclavian artery. It begins at the first rib thoracic artery, while the subscapular artery and ends at the inferior border of the pectoral and the anterior and posterior circumflex hu- major muscle, where is becomes the brachial meral arteries arise from the last segment (3, artery. In the axillary region it is surrounded 4, 5, 6). by the branches of the brachial plexus, with the Anatomical variations of the axillary artery median nerve’s initial segment placed on its branches are very common. These may occur anterior surface (1, 2). The pectoralis minor as common trunks that usually arise from the muscle divides the axillary artery into three second and third part of the axillary artery. parts. The first part is located between the Most of the described variations involve the clavicle, clavipectoral fascia and the superior subscapular artery, which may provide the lat- border of the pectoralis minor muscle, and it is eral thoracic artery and the anterior and poste- also contacting the first digitations of serratus rior circumflex humeral arteries. Nevertheless, anterior. The second part is behind pectoralis the origin of the lateral thoracic artery is still minor and anterior to subscapularis. The last a highly controversial topic. Described origin part begins at the inferior border of pectoralis variations include different parts of the axillary minor and it is covered by pectoralis major. artery and a common trunk with the thoraco- According to published data, the axillary artery acromial artery or subscapular artery (7). Ac- 299 Tamás-Csaba Sipos et al. Fig. 1. Origin of TSA and TAA from AA 2nd part Fig. 2. SSA origin from AA 2nd part 1. Axillary artery (AA); 2. Axillary vein (AV); 1. Subscapular artery (SSA); 2. Lateral thoracic 3. Thoraco-acromial artery (TAA); 4. Superior artery (LTA); 3. Thoracodorsal artery (TDA); thoracic artery (TSA). 4. Circumflex scapular artery (CSA) cording to certain studies, approximately 23 va- artery, the thoraco-acromial artery and the sub- riations of origin of the axillary artery branches scapular artery. The lateral thoracic artery have been described (5). comes from the subscapular artery. According to publications on the subject, the CASE REPORT most frequent origin variations are those of the A formalin fixed male human cadaver has lateral thoracic artery that may come from dif- been dissected during teaching classes for med- ferent branches or parts of the axillary artery ical students at the Anatomy and Embryology (7). In the majority of the cases the lateral Department of the University of Medicine, thoracic artery comes from the second part of Pharmacy, Science and Technology of Târgu the axillary artery. This report describes its Mureş. Several origin variations of the axillary origin from the subscapular artery. Other re- artery branches have been identified. The sec- ports describe this anatomical variation in ond part of the axillary artery gives off the 4-33.7% of the cases (table I). Being familiar superior thoracic artery (STA) and the thoraco- with possible variations, including the origin of acromial artery (TAA) (Fig. 1). The subscapu- the lateral thoracic artery from a common trunk lar artery detaches from the posterior surface with the subscapular artery, like in our case, is of the second part of the axillary artery. The important especially in plastic or vascular sur- subscapular artery gives off its first branch, the gery, as procedures involving this region are lateral thoracic artery (LTA) (Fig. 2), and then quite frequent. it bifurcates into the thoracodorsal artery and Marios Loukas et al. published a study with the circumflex scapular artery. The anterior and 420 cadavers; they dissected a total of 840 posterior circumflex humeral arteries arise superior limbs. They observed that in most of from the third part of the axillary artery, which the cases (67.62%) the lateral thoracic artery corresponds to the classical description. was a branch of the thoraco-acromial artery, in 17.02% of the cases it was a direct branch of DISCUSSION the second segment of the axillary artery, and Anatomical variations of the axillary artery in 3.93% of the cases it made a common trunk branches are quite common. Studies regarding with the subscapular artery (7) (table II). vascular supply of the pectoral girdle described The study published by Reddy MV. et al. in approximately 23 origin variations of the axil- 2016 showed that in 60% of the cases the lat- lary artery branches (5). eral thoracic artery was a direct branch from In this case report we described an ana- the second part of the axillary artery, which tomical variation, where the second part of the corresponds to the classical description. The axillary artery provides the superior thoracic second most frequent variant for the origin of 300 Variation of the Origin of the Lateral Thoracic Artery. Case Report TaBLE I Frequency of lateral thoracic artery originating from subscapular artery (SSA) Article/Case report Origin of LTA from SSA Number of cases Rajesh A. et al (2012) (4) 22.5% 9 Xhakaza NK. et al (2014) (9) 33.7% – Marios L. et al (2014) (7) 3.93 % 33 Thaer MF. et al (2010) (11) 5% – Bhavya B.S et al (2018) (8) 7.2% 4 Deepak AP. et al (2016) (13) 5% - Dimovelis I.et al (2017) (3) – 1 Jawed A. et al (2016) (12) – 1 Jahanshahi M.et al (2017) (10) – 1 TaBLE II Comparison of origin variants of the lateral thoracic artery (percent and number of cases) Reddy MV. et al Loukas M. et al Bhavya BS et al Type of origin (2016) (5) (2014) (7) (2018) (8) LTA 10 cases 420 cases 27 cases with STA 5% From first part with TAA 10% 67.62% directly – classic origin 60% 17.02% 81.5% with TAA 20% From second part with SSA 0% 3.93% 7.2% multiple branches of LTA 3.09% from second part of AA directly 5% From third part from TDA 5% 9.5% Absent 3.33% Double LTA 1.8% the lateral thoracic artery was the thoraco-ac- 67%, while those from the subscapular artery romial artery (30%) (originating from the sec- range from 4% to 33.7% (tables I and II). ond part – 20% and the first part – 10%). This study did not report any case where the lateral CONCLUSION thoracic artery comes from the subscapular ar- Published studies report multiple variations tery (5) (table II). regarding the origin of the axillary artery Bhavya BS. et al. (2018) studied 27 cadavers branches. Most commonly, the lateral thoracic for variations of the axillary artery. In 44 cases artery originates from the subscapular artery, (81.5%) they described the classical origin of which is the case in our study as well. the lateral thoracic artery, and in 4 cases (7.2%) they found a common trunk for the lateral ABBREAVIATIONS thoracic artery and the subscapular artery (8) AA – axillary artery (table II). AV – axilary vein Table II lists the most frequent origin variant SSA – subscapular artery of the lateral thoracic artery; most of the stud- STA – superior thoracic artery ies describe the classical origin from the second TAA – thoraco-acromial artery part of the axillary artery (17%-81%). Reports LTA – lateral thoracic artery about the lateral thoracic artery originating from TDA – thoracodorsal artery the thoraco-acromial artery range from 10% to CSA – circumflex scapular artery 301 Tamás-Csaba Sipos et al. REFERENCES 1. Seres-Sturm L, Pávai Z, Seres-Sturm M, Dénes L. A végtagok anatómiája. University Press Târgu Mureş 2006, 66-67. 2. Paulsen F, Waschke J. Sobotta, Atlas of Human Anatomy, Urban & Fischer 2011, 15th ed., English/ Latin, Vol.1: 208. 3. Dimovelis I, Michalinos A, Spartalis E, Athanasiadis G, Skandalakis P, Troupis T. Tetrafurcation of the subscapular artery. Anatomical and clinical implications.