Degenerative lumbosacral transitional articulation: atypical increased sacral uptake on planar bone scintigraphy.

Abstract

The authors describe an atypical appearance on bone scintigraphy of a degenerative transitional lumbosacral articulation, which has not been reported before. There was moderately increased uptake in the right superior aspect of the sacrum on planar imaging and markedly increased uptake medial to the upper sacroiliac joint on SPECT imaging in a patient with low back pain. These findings indicate that the enlarged transverse process of the transitional lumbosacral vertebra articulated with the sacrum and not with the ilium. This anomalous articulation shows active degenerative disease that may be responsible for the patient's symptoms. Findings of planar imaging should be considered in the differential diagnosis of diseases involving this region and should raise the possibility of changes secondary to a degenerative transitional lumbosacral vertebra.