Postoperative discitis. Radiology of progress and healing.

The roentgenologic course of postoperative discitis is described in 111 patients examined with laminar tomography. The earliest lesion was blurring of the end plate or minor destructions, leading to cavitation of the vertebral body. Mean time from operation to the first clinical symptoms was 3 weeks. Mean time from operation to first radiologic lesions was 2 months, from operation to maximal lesions 4 months, and to the first radiologic sign of healing 5.5 months. A follow-up study was carried out and the radiologic findings were compared to those of a matched control group. A significantly higher incidence of decrease in disc height, intercorporal fusion and major osteophytes was found in the discitis group. The usefulness of laminar tomography, CT, MRI and isotope studies in the diagnosis of discitis is discussed. It is concluded that laminar tomography is a good alternative, when MRI is not available.