What is the radiographic and MRI appearance of infectious spondylitis?
Infectious spondylitis, often called “discitis-osteomyelitis,” is infection of the spine. In adults, the appearance is similar to the manifestations of septic arthritis: destruction, enhancement, and an effusion of at least one disc space and findings of acute osteomyelitis of the adjacent vertebral bodies. In children, infection of the intervertebral discs without surrounding osteomyelitis can also occur due to the vascularity of the discs. On radiography, discitis-osteomyelitis manifests as progressive endplate destruction and disc space narrowing. While not infrequently mistaken for advanced degenerative disease on either radiographs or MRI, infection can demonstrate more specific signs on cross-sectional imaging such as paraspinal and psoas abscesses and phlegmon.