Low Back Pain Part 1 – Superior Cluneal Nerve Entrapment: A Contributor to Yaoyan Syndrome

The following is an excerpt of information taught in the upcoming Module II: Low Back, Hip and Groin, which is open for registration.

Low back pain (LBP) is encountered frequently in clinical practice the cause of which is often non-specific in 85% of sufferers. (Deyo RA. 2011)

There are a few specific regions in the low back, especially with patients suffering with recalcitrant and/or chronic low back pain, that are commonly seen by acupuncturists (Callison, M. 2019).

In this article, we will discuss one of the most common regions, which consists of soft tissue attachments located on the posterior superior border of the iliac crest. The author refers to this area as the “Yaoyan region” because it encompasses the popular extra point Yaoyan. Being such a common site for chronic low back pain, the author consequently refers to this injury as Yaoyan syndrome.

Figure 1. Dotted line indicatesthe Yaoyan region on the rightand level with the L4 vertebra. The acudot indicates the location of extra point Yaoyan.

Extra Point Yaoyan & the Yaoyan Region

The extra point Yaoyanis located 3.5 cun lateral to the lower border of the L4 spinous process and has been used to treat low back pain for many centuries past(O’Connor, J.1981). Anatomically, this point is located on the superior edge of the iliac crest where the lateral aspects of the iliocostalis lumborum and quadratus lumborum muscles attach. The Yaoyan region is defined as extending from L4-L5 transverse processes medially to extra point Yaoyan laterally (Fig.1). In many patients, the Yaoyan region can extend slightly more lateral to affect the deep lateral fibers of the quadratus lumborum that attach to the iliac crest.

Yaoyan syndrome is defined as a soft tissue strain in the yaoyan region of the low back and is due to multiple causes, which will be discussed later in this article. However, a soft tissue strain may not be the only cause of the pain and we encourage the TCM practitioner to also consider a possible nerve entrapment of the superior cluneal nerve.

Figure 2. Superficial cluneal nerves. The black acudot represents the location for extra point Yaoyan

Cluneal Nerve Entrapment

When a practitioner suspects the patient’s low back pain involves the Yaoyan region, it is important to include a quick screening of superior cluneal nerves (SCN). The SCN can become entrapped in the superficial layer of the thoracolumbar fascia (TLF) and is a recognized contributor to low back pain. (Talu, G. K.2000), (Kuniya, H., 2013).

The superior cluneal nerves consist of three nerves that are the terminal ends of L1-L3 spinal nerve roots. The nerves stem deep from dorsal primary rami and travel superficially through fibrous tunnels within the superficial layer of the TLF before entering the subcutaneous tissue.The medial branch of the superior cluneal nerves is the most commonly affected and can become entrapped in the posterior TLF as it travels over the iliac crest.(Trescot, A. M. 2016). The medial SCN is in very close proximity to extra point Yaoyan. (Fig. 2).

Here is a view of one branch of the superior cluneal nerve that was retained during a recent Sports Medicine Acupuncture cadaver dissection for Module II: The Low Back, Hip and Groin. Notice the location of this nerve in very close proximity to extra point Yaoyan and the Yaoyan region.

In one cadaveric study, the researchers found that themedial branch of the superior cluneal nerve was frequently seen to be adhered between the fibrous tunnel in the TLF and where the medial branch travels over the medialiliac crest (Lu, J., 1998).

Western biomedicine treats this condition often with surgery (Matsumoto, J., 2018). A simple search in PubMed with the keywords cluneal nerve entrapment will show many articles implementing surgical treatment. A fasciotomy is performed on the dense tissue that is entrapping the tissue. (Fig. 3).

Morimoto, D., Isu, T., Kim, K., Imai, T., Yamazaki, K., Matsumoto, R., &Isobe, M. (2013). Surgical treatment of superior cluneal nerve entrapment neuropathy. Journal of Neurosurgery: Spine, 19(1), 71-75.

Figure 3. A) Top arrow indicates dense fibrous tissue entrapping the superior cluneal nerve (bottom three arrows). B) Fasciotomy performed with scissors on dense tissue entrapping the superior cluneal nerve.

However, surgery should be the last resort because loosening the dense tissue that is entrapping the nerve can be successfully performed with many other treatment modalities, such as with TCM cupping, gua sha, acupuncture and myofascial release techniques (Fig. 4). Nerve entrapments have been occurring for thousands of years and successfully treated with other means other than surgery.

Figure 4. A) Palpation of superficial angle of Yaoyan. B) Needle angle for superficial Yaoyan. C) Video of a myofascial release technique to compliment the acupuncture treatment for superior cluneal nerve entrapment.

In the large majority of Yaoyan syndrome cases, the practitioner will find an elevated ilium pelvic tilts and/or pelvic rotation. Postural imbalances lead to myofascial tension and adhesion development. Pain or muscular stiffness in the Yaoyan region can usually be reproduced with range of motion testing, such as with the thoracolumbar fascia tension test. Palpation to the Yaoyan region is necessary for confirmation.

For possible cluneal nerve entrapment, the practitioner should routinely tap on the entrapment regions to rule out or confirm that nerve entrapment as a contributing factor to the patient’s low back pain. Firmly tapping with a finger in the regions (Tinels’s sign) where the superior cluneal nerves exit as discussed previously, can increase pain and/or create a paresthesia that travels in the nerve’s trajectory when positive. It is common for the paresthesia to travel in the Yaoyan region, over the posterior superior iliac spine and/or into the upper/middle buttock region.

In the SMAC program, the Module II classes discuss the postural and muscle imbalances that can be contributing to many pain conditions, such as Yaoyan Syndrome and Cluneal Nerve Entrapment. This program teaches the practitioner how to diagnose and treat the conditions and most importantly why the condition occurred! Individual CEU classes are available.

In the SMAC program, the Module II classes discuss the postural and muscle imbalances that can be contributing to many pain conditions, such as Yaoyan Syndrome and Cluneal Nerve Entrapment. This program teaches the practitioner how to diagnose and treat the conditions and most importantly why the condition occurred! Individual CEU classes are available.

For more information on Yaoyan Syndrome, the practitioner is encouraged to review the blog article on Yaoyan and the Sinew Channels (Lau, B. 2017). In addition, refer to the textbook Sports Medicine Acupuncture: An Integrated Approach Combining Sports Medicine with Traditional Chinese Medicine (Callison, M. 2019).

A reminder to the TCM practitioner that this information is merely discussing one aspect of the body. The practitioner should examine the internal and external environments that can be contributing to the patient’s pain and dysfunction.

Next month we will present Low Back Pain Part Two — Middle Cluneal Nerve Entrapment: A Contributor to Sacroiliac Joint Pain.

Click below for more information on the Sports Medicine Acupuncture PACE Course:

References

Callison, M, Sports Medicine Acupuncture: An Integrated Approach Combining Sports Medicine with Traditional Chinese Medicine. AcuSport Education 2019. P. 656-664.

Deyo RA, Weinstein JN. Low back pain. N Engl J Med. 2011;344:363–70.

Kuniya, H., Aota, Y., Saito, T., Kamiya, Y., Funakoshi, K., Terayama, H., & Itoh, M. (2013). Anatomical study of superior cluneal nerve entrapment. Journal of Neurosurgery: Spine, 19(1), 76-80.

Lau, B. 2017 Yaoyan and the Sinew Channels. sportsmedicineacupuncture.com 2017. https://www.sportsmedicineacupuncture.com/yaoyan-channel-sinews/

Lu, J., Ebraheim, N. A., Huntoon, M., Heck, B. E., & Yeasting, R. A. (1998). Anatomic considerations of superior cluneal nerve at posterior iliac crest region. Clinical orthopaedics and related research, (347), 224-228.

O’Connor J, and Bensky D. Acupuncture A Comprehensive Text. Shanghai College of Traditional Medicine. Seattle, WA: Eastland Press. 1981; 46.

Matsumoto, J., Isu, T., Kim, K., Iwamoto, N., Morimoto, D., &Isobe, M. (2018). Surgical treatment of middle cluneal nerve entrapment neuropathy. Journal of Neurosurgery: Spine, 29(2), 208-213.

Talu, G. K., Özyalçin, S., &Talu, U. (2000). Superior cluneal nerve entrapment. Regional Anesthesia & Pain Medicine, 25(6), 648-650.

Trescot, A. M., &ABIPP, F. (Eds.). (2016). Peripheral nerve entrapments: clinical diagnosis and management. Springer.