Pyogenic vertebral osteomyelitis of the posterior elements.

Lone pyogenic involvement of the posterior elements of the vertebrae is a rare event. We present two cases of isolated lumbar vertebral infection of the posterior elements and review 13 cases previously reported in the literature. Clinical presentation, laboratory and radiographic findings, microbiological etiology, and treatment were evaluated. Back pain, an elevated erythrocyte sedimentation rate, and computed tomography or magnetic resonance imaging were most useful in identifying the presence and extent of infection. Antibiotic therapy with or without surgical intervention was successful in all cases.