Pedicle marrow signal intensity changes in the lumbar spine: a manifestation of facet degenerative joint disease.
OBJECTIVE
Signal intensity changes in lumbar pedicles, similar to those described in vertebral body endplates adjacent to degenerated discs, have been described as an ancillary sign of spondylolysis on MRI. The purpose of this study was to determine whether pedicle marrow signal intensity changes also occur in association with facet degenerative joint disease.


METHODS
Eighty-nine lumbar spine MRI examinations without spondylolysis were reviewed for marrow signal intensity changes in pedicles and vertebral bodies as well as for facet degenerative joint disease.


RESULTS
Five percent (46/890) of lumbar pedicles in 23 patients had marrow signal intensity changes. Ninety-one percent (42/46) of the abnormal pedicles had adjacent degenerative joint disease of the facets, while only 21% (189/890) of normal pedicles had adjacent facet degenerative joint disease (p<0.001). Eighty-nine percent (41/46) of the pedicles with marrow signal intensity changes had adjacent degenerative disc disease.


CONCLUSIONS
Pedicle marrow signal intensity changes are not a specific sign of spondylolysis; they are commonly seen with adjacent facet degenerative joint disease in the absence of spondylolysis. Pedicle marrow signal intensity changes are probably a response to abnormal stresses related to abnormal motion or loading caused by the degenerative changes in the spinal segment.
Department of Radiology, University of Virginia Health System, Charlottesville 22908, USA.
J L
JL
Morrison
P A
PA
Kaplan
R G
RG
Dussault
M W
MW
Anderson
D000328:Adult; D000368:Aged; D003937:Diagnosis, Differential; D006801:Humans; D017116:Low Back Pain / Q000175:diagnosis* / Q000209:etiology; D008159:Lumbar Vertebrae / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D013169:Spondylolysis / Q000150:complications / Q000175:diagnosis*