The linear intravertebral vacuum: a sign of benign vertebral collapse

We describe 11 patients with radiographically visible linear intravertebral vacuums to increase awareness of this benign finding that is diagnostic of ischemic necrosis of the vertebral body (Kümmell's disease).

We retrospectively reviewed the radiologic and clinical histories of 11 patients seen at our institution between 1991 and 1997 in whom the linear intravertebral vacuum phenomenon had been diagnosed. Imaging included plain radiographs in all patients, CT scans in three, bone scintigrams in three, and MR images in three.

Twelve linear intravertebral vacuums associated with vertebral compression deformities were visible in 11 patients from T8 to L2, four at T12, and four at L1. Of the 12 linear intravertebral vacuums, seven (58%) were seen by the initial interpreting radiologist. The mean age of these patients was 76.6 years. The female:male ratio was 10:1. During the period of analysis, two patients were known to have malignancy, one with metastasis to the spine but not to the affected vertebral body. One patient, who underwent equivocal MR imaging for malignancy, later underwent bone biopsy, which showed no neoplasm within the collapsed vertebra. Of the remaining nine patients, one was undergoing chronic corticosteroid therapy and another had a history of radiation therapy to the spine. Seven of the 11 patients had histories of falling, prompting radiographs of the spine. All 11 patients were radiographically osteopenic. Ultimately, none of the patients had clinical evidence of neoplasm or infection involving the affected vertebral body.

Recognition of the near-certain benign significance of a linear intravertebral gas collection revealed by radiography may prevent unnecessary imaging or biopsy in a patient with a suggestive vertebral compression deformity.