Spontaneous staphylococcal abscess of psoas muscle

: An abscess of the psoas muscle is a rare occurrence and pathogenetic interpretation usually proves difficult. Abscessing of the psoas may be due either to direct diffusion of infections of adjacent structure or to hematogenous spread. However, not uncommonly, a "spontaneous" abscess occurs, which cannot be correlated to other sites of infections or sepsis. The Authors describe two cases of abscesses of the psoas muscle following Staphylococcus aureus sepsis of unknown origin.