Discitis Osteomyelitis

68-year-old female with a history of fever and progressive back pain. There is loss of disc height at the L3-L4 disc level with irregularity and erosions of the associated endplates. There is extensive fluid and stranding which extends anterior to the L3-L4 disc as well as more posteriorly into the ventral epidural space from the L2-L3 disc level to the L4-L5 disc level. There is an abscess and associated phlegmon which effaces the thecal sac and results in moderate spinal stenosis. The postcontrast fat saturated T1-weighted images demonstrate profound enhancement of the L3 and L4 vertebral bodies, as well as the abscess in the ventral epidural space. This is a case of discitis osteomyelitis with an associated epidural abscess. Discitis osteomyelitis most commonly affects the lumbar region with the next most common site being the thoracic spine. Staphylococcus aureus is the most common pathogen.