Post-operative intervertebral discitis. Evaluation of 12 cases and study of ESR in the normal postoperative period.

Twelve cases of intervertebral discitis following lumbar discectomy were evaluated and ESR was assessed in 70 patients operated on and without evidence of postoperative infection. Six of the intervertebral discitis patients were studied retrospectively and 6 prospectively. In the retrospective group, patients reported that symptoms appeared on average 15 days after the operation. Antibiotic treatment generally began 31 days after the operation and lasted 62 days; symptoms regressed after 3.9 months. All patients showed long-term radiographic vertebral changes and osteolysis in the cases treated later. In the prospective group, the first symptoms appeared on average 5 days after the operation, treatment started after 8 days and lasted 41 days. Symptoms regressed after 1.8 months. There were only 3 cases of vertebral radiographic changes. In both groups, ESR was always more than 70. The most useful diagnostic imaging tests were conventional tomography and MRI. Needle biopsy had no effect on the length of treatment. In 14% of patients without infective complications, ESR increased noticeably a week after the operation but, in contrast to the intervertebral discitis patients, it did not then continue to increase. Close post-operative observation permitted early detection of intervertebral discitis. Early and high-dose antibiotic treatment, even if unspecific, can resolve this infection in a few weeks.