Could my pain have been misdiagnosed as sciatica?

Pain is often misdiagnosed.Superior cluneal nerve entrapment is hard to diagnose and is often misdiagnosed as sciatica.

If you are experiencing pain in low back and buttock, it may be related to a problem with a nerve. The nerve may be the sciatic nerve, which is located fairly low on the body beneath the sacrum and pelvic bone. Or it may be the cluneal nerve, which is located outside the spot where the sacrum and pelvic bone come together. 

Okay, so two different nerves in two different spots. So far, so good.

But brace yourself for another unusual word: the cluneal nerve travels through a fibro-osseus tunnel (we warned you!) tunnel. That tunnel is not unlike the carpal tunnel in the wrist and the cluneal nerve is not unlike the median nerve. That is to say: just like the median nerve can get squeezed in the carpal tunnel, the cluneal nerve can get squeezed in its fibro-osseus tunnel.

The result is easy to understand: pain.

Diagnosis of Superior Cluneal Dearve Entrapment Is All About Location

We’ve noted the different locations of the sciatic nerve and the cluneal nerve. Those different locations mean they can cause pain in different parts of the body. Sciatica generally involves pain in the lower part of the buttock radiating down the back of the leg. Superior cluneal nerve entrapment generally involves pain in the lower back through the buttock—but not into the leg.

It is often misdiagnosed as sciatica, but also SI joint dysfunction, arthritis, and lumbar spine degenerative disease. It is very important and even needed for the patients to have a differential diagnosis explored by their physician. They can try to compare the results of different blocks that they have and their effect on their pain. It is important not to let the doctor tell the patient if the block was successful.  It is important that the patient tell the doctor if it worked or not. Because spinal joint disease is so common, we frequently only see what we know. So, if someone has "an okay" response with one injection, but a superior cluneal nerve block is not tried to compare the result to the facet block or the epidural injection, or nerve root injection, or SI joint injection, then the patient may miss the opportunity to compare the results. They may actually find out before they have a failed spinal fusion or laminectomy, or SI joint fusion, that the superior cluneal nerve may actually be the culprit. It is also very possible that the patient may have both! This does happen more than we think, and it is one reason why patients may not see the results they wanted with one diagnosis is completely treated. If they are still having pain after spinal fusion or SI joint fusion, the patient can either "accept" the outcome or keep looking. One of the things to look for is compression or injury to the superior cluneal nerves. 

The nerve is located lateral to midline, at the low back, and crosses only into the upper buttock, though it can radiate down as far as the posterior hip. Patients may be able to find it themselves by pressing at the low back at the location of their posterior pelvic bones.

Let’s Talk About Ablation

If physical therapy, stretching, heat, ice, anti-inflammatories, and conservative measures do not help, and nerve blocks of the superior cluneal nerves have provided good evidence that this is the cause of pain, then ablation of the nerves is an option. There are several ways to ablate these nerves. Some pain management teams will "burn" the nerves with radiofrequency ablation; some may freeze them with cryoablation. This is great when they work. The only problem I have seen with these modalities is trying to cover all of the anatomic variations of where these nerves are located. So, we prefer as surgeons to take a more direct approach: surgical resection. We prefer surgically exploring the region, finding the nerves, no matter where they are located, and surgically removing them. We have seen many variations in the anatomy which can easily explain why the RFA and Cryo approaches may not be as successful in some patients as others. While the surgical approach is more invasive, it tends to provide a much better view of these nerves than the current imaging modalities such as ultrasound. Because this is essentially an operation on the skin, recovery tends to be rapid.  
 
Other options for treatment may include "electrical stimulation."      Some may try to "stimulate" the nerve to try to stop hurting with peripheral or spinal cord stimulators.  Again, due to the same anatomic variations that can make the ablation procedures challenging, this make the result of stimulators challenging as well.   Also these techniques require the permanent implant of a foreign body in the lumbar region which many patients would like to avoid. 

Get the Right Diagnosis and Clarity About Treatment

We understand that just reading this FAQ may have given you a headache—so here’s the long and short: if you are having pain in your posterior, you need to get the right diagnosis so that you can get the correct treatment. Dr. Eric H. Williams can diagnose the specific cause of your pain and explain the best course of action to correct the problem. Contact us today so that we can get started putting a stop to your pain.

Eric H. Williams MD
Specializing in reconstructive surgery and pain relief in the Greater Baltimore area.