It was found in 83.39% of subjects. The most probable source of this artery could be the first palmar metacarpal artery (56.95%), first dorsal metacarpal artery (20.62%) and a stem of the radial artery (4.75%). Exceptionally, we found one case in which a strong UDDAT was the only source of the ulnopalmar digital artery of the thumbThe use of the term “princeps pollicis artery”