Lumbar Spinal Stenosis Spondylolithesis sagitall

A 72 year-old man noted chronic low back pain, worse with standing and walking. With prolonged standing, he would develop pain and numbness radiating down the posterior thighs and calves.

Lumbar Spondylolisthesis: (Left) T1-weighted sagittal MRI; (Right) T2-weighted sagittal MRI. Note the severe canal stenosis at the L4-L5 disk level. Also note that the L4 vertebral body is displaced anteriorly over L5. This is known as spondylolisthesis.

Spondylolisthesis is defined as slippage (either forwards or backwards) of one vertebral body over the one beneath it. Spondylolisthesis may be asymptomatic or may cause back pain, radicular pain, or neurogenic claudication. It may be caused by a congenital abnormality, but more often results from a stress fracture or degenerative changes in the pars interarticularis (the area of bone at the point where the pedicle meets the lamina, articular facets and transverse process). Spondylolisthesis is graded as follows:

Grade 1 - up to 25% of the vertebral body
Grade 2 - 25 to 50% of the vertebral body
Grade 3 - 50 to 75% of the vertebral body
Grade 4 - 75 to 100% of the vertebral body

This is a case of Grade 2 spondylolisthesis.

Lumbar Spinal Stenosis: Spondylolisthesis