Pain in the butt? Neuros, don't ignore this major red flag
Key Takeaways
Industry Buzz
Foraminal stenosis is a condition that happens when narrowing in parts of your spine causes compression of your spinal nerves. This happens in the location of the neural foramen, the part of your spine where your nerves exit. This can be caused from disc herniation, degenerative disc disease, and facet arthritis, aka bone spurs." — Betsy Grunch, MD, neurosurgeon
If you’ve ever had a patient come in with that one weird pain in their butt—and not in the metaphorical sense—you’re not alone.
According to neurosurgeon Betsy Grunch, MD, who broke this down in two of her recent Instagram Reels, isolated gluteal pain can sometimes have a surprising source: the lower spine.
The intriguing case details
A 65-year-old man presented to the clinic with chronic, deep right-sided gluteal pain that'd been off and on for years—but was getting progressively worse
He’d already done the rounds: physical therapy, chiropractor visits, over-the-counter meds, even an MRI. Nothing had fully solved it. He got some relief from an epidural steroid injection, but the pain kept coming back.
Initial impressions
He didn't have the classic “shooting pain down the leg” you'd expect with sciatica. Just deep pain in the glute, making it hard to sit or walk without a limp. It didn't scream radiculopathy—but that’s exactly what it turned out to be.
Dr. Grunch reviewed his lumbar spine X-ray and MRI. The culprit? Foraminal stenosis at L4–L5 on the right side.
Related: Myths about back pain that make it worseWhy this matters
A lot of us were taught that radiculopathy follows a neat path—from back to butt to leg. But in reality, that’s not always how it shows up.
As Dr. Grunch pointed out, around 75% of patients with lumbar disc herniation will present with unilateral buttock pain only. No leg pain. No textbook pattern.
Differentials to consider in a case like this
Piriformis syndrome
SI joint dysfunction
Hamstring tendinopathy
Hip pathology
Vascular causes
And yes, foraminal stenosis (L4–L5 or L5–S1)
The key is taking a good history and getting imaging when conservative options fail.
What worked
The patient had already tried nearly everything conservative. Rather than jumping to fusion, Dr. Grunch performed a minimally invasive foraminotomy—targeting the collapsed right-sided foramen at L4–L5.
The result? He woke up pain-free.
What didn’t happen (yet)
No fusion. And that’s important. A spinal fusion might be in this patient’s future if symptoms return or if instability worsens.
But in this case, a targeted decompression was enough. As Dr. Grunch put it, we shouldn't skip steps. Start with the least invasive—and work your way up only if needed.
The clinical takeaway
If your patient has a “pain in the butt” that just won’t quit—don’t rule out foraminal stenosis just because there’s no radiating leg pain. Not all sciatica looks like sciatica.
And if the diagnosis is clear but the pain persists? A foraminotomy might be all they need to walk out pain-free.
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