The prognosis of primary-and secondary abscesses of the psoas has impr
oved since the introduction of modern imaging techniques. A review of
seven cases showed that ultrasonography consistently established the d
iagnosis. Percutaneous drainage under ultrasound guidance was performe
d in only four cases and surgery in the remaining three cases. There w
as no morbidity or mortality. Ultrasonography and computed tomography
ensure early identification of psoas abscesses and can obviate the nee
d for surgery by allowing percutaneous drainage of the fluid collectio
n.