Upper limb arterial pattern: clinical correlation and embryological perspective

A Cadaveric Study on the High Origin of the Radial Artery

INTRODUCTION

Among the upper limb's vascular variations, the radial artery's high origin from the axillary artery is rare, and literature regarding the same is limited. Anomalous origin of radial artery can cause failure of radial approach to coronary angiography and reconstructive surgeries of upper limbs and hence is of clinical significance. With this background, the current cadaveric study was planned to describe the branching pattern of the axillary artery and its variations.

METHODS

We conducted this descriptive, cross-sectional study on sixty adult human cadaveric upper limbs at the anatomy departments of Government TD Medical College, Alappuzha, and Government Medical College, Thiruvananthapuram, over two years from 2021 to 2023. The axillary artery's branching pattern and termination were noted, and the prevalence of high origin of the radial artery from the axillary artery was documented.

RESULTS

High origin of radial artery from axillary artery was observed in four (6.70%) limbs and was higher than the prevalence reported in earlier literature. Among these variations, one was a female cadaver with a bilateral high origin of radial artery arising from the third part of the axillary artery. The other two were from separate male upper limbs, both from the right upper limb.

CONCLUSION

The prevalence of the high origin of the radial artery from the axillary artery was high compared to earlier reported literature. This calls for further research in the anatomy of arterial patterns of the upper limb to avoid complications during arterial procedures of the upper limb.

Variations in Superficial Palmar Arch: Case Series with Clinico-anatomical Perspective

The superficial palmar arch (SPA) is an important anastomotic network primarily formed by the superficial branch of the ulnar artery with one of the superficial branches of the radial artery. SPA variations were observed in three out of 20 cadaveric hand specimens. Two cases of unilateral incomplete SPA and the third case of a unilateral ulnar-to-median complete SPA were recorded. The incomplete SPA was located superficial to the flexor digitorum tendons and deep to the palmar aponeurosis. SPA in the remaining 17 hands was anatomically normal, with major contributions from the superficial palmar branch of the ulnar artery and minor contributions from the superficial palmar branch of the radial artery. These variations are clinically important, especially during procedures like arterial blood sampling, cardiac catheterization, and hemodialysis. Thus, anatomical variabilities in this region may cause complications with vascular occlusion if not ascertained before the procedure.

Decoding the mechanism of vascular morphogenesis to explore future prospects in targeted tumor therapy

The growth and formation of blood vessels is an undeniably fundamental biological process crucial to controlling overall development of an organism. This phenomenon consists of two separate processes, commencing with vasculogenesis, which refers to the process of blood vessel formation strictly in embryonic stages, via de novo endothelial cell synthesis. Angiogenesis continues the formation of the vascular network via sprouting and splitting. Tumor growth is dependent on the growth and supply of blood vessels around the tumor mass. Extracellular matrix (ECM) molecules can promote angiogenesis by establishing a vascular network and sequestering pro-angiogenic growth factors. Although the methods by which tumor-associated fibroblasts (which differ in phenotype from normal fibroblasts) influence angiogenesis are unknown, they are thought to be a major source of growth factors and cytokines that attract endothelial cells. Chemokines and growth factors (sourced from macrophages and neutrophils) are also regulators of angiogenesis. When considered as a whole, the tumor microenvironment is a heterogenous and dynamic mass of tissue, composed of a plethora of cell types and an ECM that can fundamentally control the pathological angiogenic switch. Angiogenesis is involved in numerous diseases, and understanding the various mechanisms surrounding this phenomenon is key to finding cures.

The persistent median artery and its vascular patterns: A meta-analysis of 10,394 subjects

The presence of a persistent median artery (PMA) has been implicated in the development of compression neuropathies and surgical complications. Due to the large variability in the prevalence of the PMA and its subtypes in the literature, more awareness of its anatomy is needed. The aim of our meta-analysis was to find the pooled prevalence of the antebrachial and palmar persistent median arteries. An extensive search through the major databases was performed to identify all articles and references matching our inclusion criteria. The extracted data included methods of investigation, prevalence of the PMA, anatomical subtype (antebrachial, palmar), side, sex, laterality, and ethnicity. A total of 64 studies (n = 10,394 hands) were included in this meta-analysis. An antebrachial pattern was revealed to be more prevalent than a palmar pattern (34.0% vs. 8.6%). A palmar PMA was reported in 2.6% of patients undergoing surgery for carpal tunnel syndrome when compared to cadaveric studies of adult patients in which the prevalence was 8.6%. Both patterns of PMA are prevalent in a considerable portion of the general population. As the estimated prevalence of the PMA was found to be significantly lower in patients undergoing surgery for carpal tunnel syndrome than those reported in cadaveric studies, its etiological contribution to carpal tunnel syndrome is questionable. Surgeons operating on the forearm and carpal tunnel should understand the anatomy and surgical implications of the PMA and its anatomical patterns.