A Comparative Study of Spinal Bone SPECT versus X-ray Radiograph, CT or MRI in Patients with an Acute Compression Fracture of a Thoracolumbar Vertebral Body

Abstract

We retrospectively studied the spinal bone SPECT images of 84 consecutive patients (27 men, 57 women;mean age, 71.3 years;age range, 52 - 89 years) with acute non-traumatic collapse of a vertebra in the thoracolumbar spine. Of the 84 patients, 59(70.2%) had a history of malignancy. Twelve patients (14.3%) had a vertebral metastasis and 72(85.7%) had an osteoporosis in the vertebra. There were no clear differences between the vertebral body uptake patterns in the group with metastasis and the group with osteoporosis alone, although a horseshoe pattern tended to occur in the patients with a osteoporotic lesion (25% vs.42%). Increased pedicle uptake was seen in 20 patients (23.8%, 20/84), 9 of whom (75.0%, 9/12) had a vertebral metastasis and 11(15.3%, 11/72) did not (p<0.001). A pedicle sign or invasion on radiographs and/or CT images was seen in all 9 patients with metastatic disease patients (100%) but not in any of the11patients with osteoporosis. When pedicle uptake on SPECT images and the pedicle sign or invasion were used to diagnose bone metastasis in these84patients, sensitivity, specificity, positive predictive value, negative predictive value were 75.0%(9/12), 84.7%(61/72), 45.0%(9/20), and 95.3%(61/64), respectively. Radiograph and CT remain to be important studies to diagnosis acute non-traumatic collapse of a vertebra, although a spinal SPECT study provides some additional information.