Imaging basis of disc space infection.

Infective spondylitis, the combined infection of the osseous vertebral structures and disc space, constitutes 2% to 4% of all cases of osteomyelitis, and is increasing in prevalence. Differences in clinical and imaging presentation between children and adults are explained by developmental anatomic differences. Radiographic evaluation of infective spondylitis has previously included plain films, CT scans and nuclear imaging. However, MRI is emerging as the most sensitive and specific modality for early detection of pyogenic and nonpyogenic infections and their complications, as well as in follow-up evaluation. Degenerative disc disease, seronegative spondyloarthropathies, and spondyloarthropathy associated with long-term hemodialysis may mimic the imaging abnormalities of infective spondylitis.