Innominate variant artery in the first web space

Abstract

Numerous variations are characteristic for hand anatomy. Although a lot of work has been done in the field, a detailed description of the branches of the radial artery is still missing. The aim of this study is to determine the incidence and diameter of the accessory artery, which can be found running on the dorsal surface of the interosseus dorsalis primus muscle, to deliver the detailed description of this arterial variation and based on that to suggest a systematic name of the artery which would be in line with Terminologia Anatomica. We used 133 complete donor bodies and 237 cadaverous hands in our study, giving us a total sample size of 503 samples. When possible, we determined the age of the donors which was between 62 and 90 years. We performed detailed anatomical dissection to determine the individual branching. We also measured the diameter of selected arteries. When relevant we performed statistical comparisons. To do that we first applied Shapiro-Wilk test to determine the normality of distribution and after that we used Mann-Whitney U test and One-way ANOVA. The variation of interest was found in 11.93% of cases. Based on the anatomical differences we determined four types of branching, type 1-3 forming the anastomosis with superficial palmar arch (being considered as positive findings) and type 4 which did not form this anastomosis (thus considered to be a negative finding). We successfully determined the incidence of this arterial variation on a sufficient sample size. We also described the anatomy of this branching in detail and were able to determine four types of this branching. After careful consideration of these findings we proposed the new name for this artery and suggest to use the name superficial dorsal branch of radial artery. This could contribute to a better understanding of this branching and potential use in clinical practice.