Conjoined nerve root

Case contributed by Dr Andrew Dixon


Lower back and leg pain, right greater than left. Previous right L5 laminectomy.

Patient Data

Age: 35 years
Gender: Female

Previous right L5 laminectomy and microdiscectomy. Residual circumferential disc bulge with prominent posterior broad-based disc bulge and focal protrusion on the right at the subarticular recess.  Right L5 and S1 nerve roots share a common dural sheath (conjoined). Right subarticular recess narrowing by disc combines with the conjoined location of the right S1 nerve root to result in significant impingement the traversing right S1 nerve root.  Moderate right neural foraminal stenosis with mild flattening of the exiting L5 nerve root. Mild left L5-S1 subarticular recess narrowing and neural foraminal stenosis without neural compression.

Case Discussion

Conjoined right L5 and S1 nerve roots which can be seen to share a common dural sheath. This often predisposes the lower nerve root to impingement in the subarticular recess which is the case here.  

How to use cases

You can use Radiopaedia cases in a variety of ways to help you learn and teach.

Creating your own cases is easy.