ANOTHER STUDY FINGERS ENTRAPMENT OF THE SUPERIOR CLUNEAL NERVE AS CAUSE OF BACK & LEG PAIN
I've written extensively about the thoracolumbar model of pain, which many experts argue constitutes as great as 7 in 10 cases of low back pain (HERE, HERE, HERE, HERE, HERE, or HERE). Why is this important to grasp? Largely because the DISC MODEL of low back pain ---- a model that routinely leads to THORACOLUMBAR FASCIA-DISRUPTING SPINAL SURGERIES --- is still widely (almost universally) the model being used in the average medical practice.
A few days ago, seven researchers from three different Japanese hospital's neurosurgery departments published a study in the Asian Spine Journal titled Characteristics of Low Back Pain due to Superior Cluneal Nerve Entrapment Neuropathy, revealing just how easy it is to confuse run-of-the-mill low back pain with pain caused by CLUNEAL NERVE ENTRAPMENT. These authors, however, also determined that by comparing the responses of certain questions on the ROLAND MORRIS DISABILITY QUESTIONNAIRE they could, with an increased degree of certainty, ascertain whether or not a person's back pain was being driven by SPINAL STENOSIS or by an entrapment of the superior cluneal nerve. For the record, entrapment neuropathies of all kinds are common (HERE, HERE or HERE).
After discussing how prevalent low back pain is worldwide, the authors discussed what makes superior cluneal nerve entrapment unique. "Although experimental studies have indicated that LBP may originate from various spinal structures, its etiology is non-specific in 85% of patients." In other words, most low back pain is of unknown or "non-specific" origin. However, "non-specific back pain" (HERE, HERE or HERE) just got a bit more specific. These authors indicated that the superior cluneal nerve --- a sensory nerve that comes from the lower thoracic and lumbar spine --- "passes through the thoracolumbar fascia". Why is this significant? Simply watch these seven second videos side-by-side to see for yourself (HERE). Or pay attention to one of this study's many conclusions, "the incidence of superior cluneal nerve entrapment neuropathy in patients with low back pain is unexpectedly high." Just how high is the question we are going to try and answer today.
The authors divided 69 geriatric patients into two groups --- the first group consisted of those who had recently undergone nerve blocks or surgical release for entrapment neuropathy of the superior cluneal nerve (eight of these also had a history of previous surgery for lumbar spinal stenosis). 21 of the 35 "experienced LBP only, whereas 14 experienced LBP associated with leg symptoms." The second group had recently undergone surgical treatment for spinal stenosis. In the stenosis group "30 patients experienced LBP associated with leg numbness or pain," while the rest "experienced leg symptoms only".
Be aware that none of the stenosis patients met criteria for being diagnosed with superior cluneal nerve entrapment. If patients from the nerve entrapment group had their pain relived by an anesthetic injection at the area where the nerve exited the thoracolumbar fascia, the diagnosis of entrapment was confirmed. For those whose pain could not be relived long-term in this manner, the authors took a surgical approach.
These neurosurgeons found that a TRIGGER POINT was invariably present at the site of pain and "carefully dissected so that the superior cluneal nerves were identified." The surgeons then traced the nerves back to the point they came through the thoracolumbar fascia and simply "released" them (they used "microscissors," to make the hole slightly bigger) "until reaching the point at which the superior cluneal nerve was free of kinks". 10 of those from this second group required surgical release. What was discovered from this experiment?
Entrapment of the cluneal nerve tends to cause significantly more pain and dysfunction than lumbar spinal stenosis (a shrinking of the spinal canal). On the pain / disability scale used by these authors (Roland Morris), "the scores were significantly higher in the SCN entrapment group than in the spinal stenosis group." How did this shake out specifically? Because I've not only been treating CHRONIC PAIN PATIENTS for thirty years, but personally dealt with a degree of chronic pain myself a number of years ago (HERE), not to mention spending lots of time with my post-polio father-in-law (HERE), I have a pretty good idea of what chronic pain can do to a person. Essentially, it saps your strength, stamina, energy and motivation, while draining you emotionally and mentally (cognitively). In other words, it affects every part of your being, body and mind.
"Patients with SCN entrapment exhibited significantly higher Roland Morris Disability Questionnaire scores and greater levels of disability due to LBP compared with patients with lumbar spinal stenosis. These findings further demonstrate that SCN entrapment can affect physical and psychological functions. For seven items, the ratio of positive responses was higher in the cluneal nerve entrapment group than in the spinal stenosis group: staying at home most of the time (Question 1), trying to get other people to do things (Question 8), trying not to bend or kneel down (Question 11), sitting down for most of the day (Question 20), avoiding heavy jobs around the house (Question 21), tending to be more irritable and short-tempered with people than usual (QN22), and going upstairs more slowly than usual (Question 23). There were no high scores in the spinal stenosis group."
Why might this paragraph be important to understand? Mostly because entrapment of the superior cluneal nerve has the potential to act as a mimic. "Because these symptoms are similar to those of lumbar disorders, there is a potential for misdiagnosis." For one, it can mimic DEGENERATIVE DISC DISEASE (or HERE). PIRIFORMIS SYNDROME can also mimicked by entrapment of the superior cluneal nerve, chiefly in that they both cause buttock / hip pain. However, make sure to note that the nerve entrapment group would rather sit, while the piriformis group can't sit (or if they do they suffer tremendously). And let's not forget SACROILIAC PAIN.
I bring these results to you because in at least a portion of those struggling with either SCN or lumbar stenosis, there are things you could be doing conservatively that do not involve injections or surgeries. For the stenosis group, SPINAL DECOMPRESSION or INVERSION THERAPY can prove tremendously helpful, along with LASER THERAPY, certain SPINAL ADJUSTMENTS, etc, etc. However, for those who may have entrapment of the superior cluneal nerve, TISSUE REMODELING MIGHT PROVE EFFECTIVE, and is certainly worth a try. I use the word "try" only because I tell my patients they will know after a single treatment whether or not this approach will prove helpful for this sort of nerve entrapment (HERE is a cool example of 23 years of chronic low back pain gone after a single treatment).
As I've always stated, every problem should be treated as though it were "SYSTEMIC". In essence this means that some diet and lifestyle changes are probably in order (HERE is a protocol designed for at least some of you struggling with low back pain). While not a solution for everyone or every back problem, if you are looking for a starting point to begin researching from, it's good for that. If you know people who could benefit from this information, be sure to get it to them. A nice way still happens to be liking, sharing, or following on FACEBOOK.
Dr. Schierling completed four years of Kansas State University's five-year Nutrition / Exercise Physiology Program before deciding on a career in Chiropractic. He graduated from Logan Chiropractic College in 1991, and has run a busy clinic in Mountain View, Missouri ever since. He and his wife Amy have four children (three daughters and a son).