Duplicate Radial Artery Variation: A Comprehensive Analysis With Case Report, Literature Review, Embryological Insights and Clinical Significance.

Thorough knowledge of the anatomical variations of the arterial pattern of the upper limb is of high clinical importance in many medical fields, from surgery to nursery and anesthesiologic practice. During a routine dissection at the Anatomy Department of the Medical University of Plovdiv, a rare variation of the vascular system in the upper limb of a study cadaver was observed. The exhibited variation was the occurrence of a brachioradial artery (BRA) that ran along the main axis of the arm, superficially to the median nerve. After dissection of the cubital fossa, an unusually underdeveloped radial artery was also spotted. Per our knowledge, such a type of duplicate radial artery, the coexistence of a BRA and an underdeveloped radial artery has not been reported in the relevant literature on the topic. The underdeveloped radial artery gave a major branch, the recurrent radial artery, a branch usually given by the brachial artery or the BRA in case of a BRA variation. Variations in the arterial pattern could potentially give insight into the features of the embryological development of the vascular system.

Sternalis muscle--a riddle that still awaits an answer short communication.

One important variant of the panniculus carnosus remnants--a superficial muscle layer in the thoracic region typical for lower mammals, is an often found variation known by the name of sternalis muscle. It was discovered for the first time by Cabrolius in 1604 and identified precisely in 1726 by Du Puy. Even today, the variation is still an object of description and attempted to be classified and defined. We found an abnormal muscle band known as sternalis muscle (m. sternalis). The variation was accompanied by a partial bilateral agenesia of the pars sternocostalis of the pectoralis major muscle. Although m. sternalis was first described 3 centuries ago, its origin is still unclear. Some authors suggest that it originates from adjacent muscles such as the sternocleidomastoid muscle, pectoralis major muscle, rectus abdominis muscle, etc. Kadanov considers the muscle a remnant of panniculus carnosus, a muscle layer located immediately under the skin in lower mammals. Our case confirms the hypothesis of the pectoral origin of m. sternalis. It is not only a rare variation of interest to morphologists, but also a structure which is important for clinicians. The location of the muscle makes it essential for general and plastic surgeons as well as for the specialists in imaging diagnostics. In conclusion we consider that this anomaly belongs to the group of the rudimentary structures in human beings, which appear to be more variable. The suggestion of its development as a possible phylogenic regularity in the evolution makes it all the more important for the morphological science and medical practice.