Postoperative intervertebral disc space infection.

Intervertebral disc space infection is an uncommon, but serious, complication of disc surgery. By a retrospective chart review, we identified 27 patients at our institution who had a postoperative disc space infection; 14 were diagnosed and treated within the last 5 years. The characteristic symptoms were severe spinal pain and limited spinal mobility beginning 7 to 30 days postoperatively. The key physical findings were paravertebral muscle spasm and marked mechanical signs. The key laboratory findings were an elevated erythrocyte sedimentation rate and a mildly elevated white blood cell count. The diagnosis was based on the clinical presentation and early radiographic changes in the vertebral bodies adjacent to the involved disc, especially irregularities of the cortical margins seen best by tomography. Definitive bacteriological diagnosis by Craig needle biopsy was attempted in 14 patients; 7 had positive cultures and all yielded a Staphylococcus species. The usual treatment consisted of the administration of antistaphylococcal antibiotics and immobilization of the spine with a spica cast, a plastic body jacket, or complete bedrest. The final radiographic findings showed bony fusion or bridging in 19 patients, and 25 patients had a pain-free recovery after 1 to 9 months. There was 1 recurrent infection, and 3 patients eventually required an anterior discectomy and fusion. Based on a review of our own cases and those reported in the literature, we stress the importance of spinal tomography in establishing the diagnosis of postoperative disc space infection at a relatively early stage in a patient who is suspected of having this condition on the basis of typical symptoms and signs combined with an elevated sedimentation rate.(ABSTRACT TRUNCATED AT 250 WORDS)