Background We sought to define the crude prevalence rate of the persistent median artery (PMA) (palmar type). Although there is no reported case in the anesthetic literature, a few sporadic case reports and series reported in anatomical and orthopedic journals describe an incidence of between 1.5% and 27.1%.

Methods We conducted a prospective observational study to define the crude prevalence of the PMA (palmar type) by scanning 100 forearms of 50 volunteers using a high-frequency ultrasound probe.

Results We found 19 PMAs in 13 individuals, thus giving a prevalence of 19%. Other arterial variants were also identified within this population.

Conclusions Anatomical variations of the blood supply to the forearm and hand can be identified with available high-frequency ultrasound equipment. Arterial variants immediately adjacent to the median nerve may occur in approximately 1 in 5 limbs. Practitioners should actively seek their presence or absence.