Table 1.

Categories used to classify structural abnormalities on lumbosacral MRI

MRI ABNORMALITIES	COMMON DESCRIPTIVE TERMS*
Degenerative disk	Bony—end plate changes, osteochondral bar, osteocartilaginous bar, osteophytes Disk—annular tear, bulge, degeneration, dissection, height loss, high-intensity zone, spondylosis, signal change
Disk herniation	Disk—herniation, extrusion, protrusion, sequestered
Spinal stenosis	Central canal stenosis Facet—arthropathy, hypertrophy Lateral recess, foraminal stenosis Ligamentous hypertrophy
Instability	Anterolisthesis Lateral, rotatory listhesis Retrolisthesis Spondylolisthesis
Spinal deformity	Kyphosis Scoliosis
Previous surgery	Decompression—discectomy, epidural scar, laminectomy, laminotomy Fusion—bone fusion, bone mass, disk prosthesis, facet screw, fusion mass, instrumentation, metal artifact, pedicle screw

MRI—magnetic resonance imaging.

^*For extracting information from the MRI reports, the common descriptive terms were considered synonymous with the corresponding MRI abnormality on the left.