Lumbar Lateral Recess Stenosis
What it is
Just inside the spinal canal, before each nerve heads out to its own exit, it travels through a narrow gutter along the side called the lateral recess. In lateral recess stenosis, that gutter narrows — usually from a bulging disc, a thickened ligament, or an enlarged facet joint — and catches the nerve as it passes. Think of it as a merge lane that has gotten too tight, one step before the off-ramp (the foramen).
What it feels like
Like foraminal stenosis, this usually irritates a single nerve, so symptoms tend to run down one leg in that nerve’s pattern — pain, numbness, tingling, sometimes weakness. Symptoms are often positional, worse with standing or walking and better with sitting or leaning forward.
How we diagnose it
Your symptom pattern and a focused exam suggest which nerve is caught, and an MRI shows the narrowed recess and the level. The picture and your symptoms need to match before we act on them.
How we treat it
Non-surgical care comes first for most people. A pinched nerve hurts partly from inflammation around it, not only from the pressure itself, so a steroid injection, anti-inflammatory medication, and time often settle it. I usually want to give this a fair trial of at least six weeks, since most people improve and avoid surgery:
- Physical therapy and activity adjustments
- Anti-inflammatory medication when appropriate
- A targeted (transforaminal) steroid injection to calm the irritated nerve and confirm the level
If symptoms persist despite a fair trial, the good news is that the lateral recess can usually be opened from the back with a focused decompression that frees the nerve while preserving enough of the joint to keep the level stable — so a fusion is usually not required here. A fusion enters the conversation only if the segment is already unstable or slipping. The decision rests on how much your life is limited, not on the scan by itself.
The science — for the curious
The lateral recess is a classic spot for a nerve to get caught, and it explains a common puzzle: someone can have clear one-leg symptoms even when the central canal looks only mildly narrowed — the crowding is in the gutter, not the middle of the canal. It is also a place I can usually decompress without fusing, which matters: a fused level shifts extra load onto its neighbors and can speed their wear, so I favor the least destabilizing operation that solves the problem.
Learn more
American Academy of Orthopaedic Surgeons — OrthoInfo: orthoinfo.aaos.org
North American Spine Society — KnowYourBack: knowyourback.org
This handout is general education about a common condition and does not replace the personalized advice we discuss in clinic. If anything here does not match what we talked about, what we talked about wins — please ask me.