Pyogenic vertebral osteomyelitis of the posterior elements.

Three cases of pyogenic vertebral osteomyelitis involving only the posterior elements are presented. This unusual location creates difficulty in distinguishing vertebral osteomyelitis from neoplasms and arthridites. All three patients had involvement of the articular facet, a helpful indication against neoplasms. However, vertebral osteomyelitis should be differentiated from erosive arthridites.