Correlation Between Cervical Spinal Stenosis and the Morphology of Congenital Lumbar Stenosis

Neurogenic claudication from lumbar spinal stenosis can be either due to degenerative pathology or congenitally narrowed spinal canal. Recent cadaveric studies have linked existence of congenital lumbar stenosis with cervical spinal stenosis. Dagi et al. defined this clinical picture as tandem stenosis noting an incidence of 5%-25% in individuals. It has been our experience that sagittal MRI morphology of congenitally narrowed lumbar spine can differ between individuals with 3 characteristic presentations. The morphological categories include: (1) “Rapidly tapering” stenosis in which the canal begins to gradually narrow from the thoracolumbar junction to a peak area of stenosis at L5-S1. (2) “hour-glass” type in which the canal begins to narrow at the thoracolumbar junction to a peak area of stenosis around the L3-4 level, with the canal opening again distally. (3) Global congenital lumbar stenosis in which the entire lumbar spine shows a symmetrically stenotic canal.