myofascial techniques BY TIL LUCHAU

A peripheral nerve’s connective tissue includes the inner perineurium (light tan), which encloses bundles of axons (dark beige), and the epineurium (green), the outer wrapping of the nerve, which contains the nerve’s internal blood supply (red and blue). Image courtesy Primal Pictures. Used with permission.

110 massage & bodywork september/october 2011 ASSESSING SCIATIC NERVE GLIDE, Part 2

Nerves are not wires. Although Understanding Nerve Entrapment both nerves and wires transmit In order to understand sciatic nerve entrapment, it is helpful to review electrical impulses, nerves are some important features about nerves in general, and the sciatic nerve in much more than electrical particular. The neurons that make up the sciatic nerve are the longest in cables. Nerves, because they the body—originating in the spinal cord and extending to the hip, leg, and are living, perceptive, and foot. Like all peripheral nerves, these Although living nerves are much more complex neurons are wrapped and bundled than wires, a nerve’s connective tissue layers sentient structures, are sensitive within various layers of connective are analogous to the layered wrappings tissue, the outermost layer being the around an electrical cable. Image courtesy to being crowded, confined, or epineurium (Images 1 and 3), which periodictable.com. Used with permission. is a continuation of the arachnoid and overstretched. When the sciatic dural layers surrounding the central nervous system. The connective nerve is entrapped or irritated, tissues of a nerve function to: 1. Help maintain its internal pain in the low back, buttock, electrochemical environment. 2. Carry the nerve’s intrinsic blood and lower limb is the result. vessels and sensory nerves. 3. Give the nerve its structure, As explained in the last article tensile resilience, and elasticity. (“Assessing Sciatic Pain,” July/ Impingement (compression or August 2011, page 110), sciatic pain tension) on the nerve impairs all three arises from either axial origins of these functions, causing internal (typically at the spinal nerve roots), inflammation of the nerve, reducing or from appendicular causes (distal its blood flow, and diminishing The epineurium (pink) and its finer enervating entrapments in the buttocks, hip, or its ability to glide and stretch. sensory filaments (nervi nervorum, yellow), leg). In this article, I will list some Elastic glide is particularly relevant which are involved in pain of the nerve itself. of the most common appendicular to our work. The long neurons within sciatic nerve entrapment sites, and the sciatic nerve stretch an additional describe one way of determining 3.5–5 inches with normal hip, knee, and where appendicular entrapment may ankle motions.1 This causes a significant be occurring. In the next article, I will amount of gliding movement between introduce hands-on methods from the epineurium and the surrounding Advanced-Trainings.com’s Advanced intermuscular septa, muscle sheathes, Myofascial Techniques series that and supporting fascias. A nerve gliding have proven both safe and effective within these surrounding connective for easing appendicular sciatic pain. tissues can be compared to a tendon’s movement within its surrounding bursa. As with other connective tissues, the epineurium sheath around

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a nerve may itself become adhered or tethered to surrounding structures; it may also become hardened and thickened from strain or injury. Since this protective sheath contains blood vessels that supply the nerve, adhesions or hardening of the epineurium can choke the nerve’s circulation, worsening the internal inflammation. Impingements on the nerve sheath may also cause pain directly—the sheath itself is highly enervated by smaller sensory nerve filaments (the nervi nervorum, Image 3) that are thought to be responsible for many cases of neuropathic pain (pain related to dysfunction of the nerve tissues themselves).2 Most importantly for manual therapists, remember that you can’t rub nerve inflammation away. This is the key point for effective work with sciatica (and other nerve pain). Since sciatic nerve inflammation is caused by pressure, applying more pressure won’t help. With this in mind, it is usually best to avoid direct manual pressure on the sciatic nerve; instead, our goal is to increase “nerve glide”: decompress the nerve’s passageways, and release nerve sheathes from adjoining structures to restore normal neural movement, freedom, and elastic sliding.

SCIATIC NERVE GLIDE TEST Appendicular sciatica can be related to sciatic nerve entrapment at any of these sites: • Under, over, through, or around the piriformis or other rotators. • Between quadratus femoris/ gluteus maximus. Because the sciatic nerve stretches as much as 5 inches with lower limb movements, the Sciatic Nerve • In the intermuscular septum Glide Test can help locate sciatic nerve entrapment sites. If knee extension and ankle dorsiflexion between biceps femoris/adductor increase sciatic symptoms, nerve tethering in the hip or leg is likely, usually at the site of pain, or magnus in the posterior thigh. at a place proximal to it along the nerve’s pathway. Images courtesy Advanced-Trainings.com. These entrapment sites can be assessed with the Sciatic Nerve Glide

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Test. To perform the test, have your Myofascial techniques (such as those from balanced strengthening client lie supine with the hip and knee we’ll describe in our next installment), (strengthening abductors, for flexed on the affected side (Image 4). as well as stretching the rotators, example, can counterbalance Direct your client to actively straighten gluteus, or hamstrings, are often hypertoned rotators and adductors). the bent knee of the raised leg (Image particularly effective ways to release the Because appendicular sciatic 5). Extending just the knee from 90 neural sheath adhesions or myofascial entrapments are most often soft- degrees to fully straight stretches the restrictions you’ve discovered with tissue restrictions, they frequently sciatic nerve about 1.5–2.5 inches; the Sciatic Nerve Glide Test. respond quite well to focused and adding ankle dorsiflexion (as pictured) This test itself can also be as thorough hands-on myofascial work. typically adds another half inch of helpful as a take-home client exercise In our next article, I’ll describe stretch.3 Thus, if straightening the to mobilize a tethered nerve. Clients hands-on techniques for working affected leg increases sciatic symptoms, should be cautioned not to do too many with the appendicular sciatic nerve nerve tethering in the hip or leg is a repetitions at one time, or to repeat entrapments you identified with the likely contributor to the sciatic pain. the maneuver more than once per day, Sciatic Nerve Glide Test. You can get even more specific so as to avoid continually irritating about where to begin your work an already inflamed sciatic nerve. Til Luchau is a member of the Advanced- by asking your client to compare Trainings.com faculty, which offers distance the sensations of straightening the OTHER CAUSES OF learning and in-person seminars throughout affected and unaffected legs, and to APPENDICULAR SCIATIC PAIN the United States and abroad. He is also a direct you to any sites of increased In addition to the soft-tissue Certified Advanced Rolfer and teaches for the pain. Nerve pain typically radiates impingements listed above, the Rolf Institute of Structural Integration. Contact distally, so the entrapment causing following issues can also contribute him via [email protected] and pain resulting from this test is usually to appendicular sciatic pain: Advanced-Trainings.com’s Facebook page. at the site of pain, or proximal to it.4 • Prolonged sitting, either from So it makes sense to start at the site direct pressure on the sciatic nerve Notes of reported pain and work the nerve from wallets, bucket seats, etc., 1 Iain D. Belth et al., “An Assessment of the Adaptive pathway proximally from there, or from postural strain resulting Mechanisms Within and Surrounding the Peripheral Nervous System, During Changes in Nerve retesting to track for any changes. from hip flexion contracture or Bed Length Resulting from Underlying Joint posterior pelvic rolling (slumping). Movement,” from: Moving in on Pain: Conference Variations to the Sciatic Nerve • Driving can increase leg tightness Proceedings—April 1995 Butterworth-Heinemann; Glide Test (not pictured) from pressing on the gas pedal, 1st edition (December 27, 1995): 194–6. 1. Increased sciatic pain when as well as from sitting (driving is 2 A.K. Asbury and H.L. Fields, “Pain Due to bringing straightened leg across also a risk factor for disc issues). Peripheral Nerve Damage: An Hypothesis,” the body (hip flexion and adduction • Hypertrophy (overdevelopment Neurology 34 (1984): 1,587–90. with knee extension) can indicate and enlargement) of the piriformis, 3 Iain D. Belth et al., “An Assessment of the Adaptive piriformis involvement. rotators, or hamstrings, especially Mechanisms Within and Surrounding the Peripheral Nervous System, During Changes in Nerve Bed 2. Placing the sole of the passive leg when combined with repetitive Length Resulting from Underlying Joint Movement.” on the table by raising the knee motions (as in prolonged exercise). 4 As mentioned in the text, the entrapment site is can help differentiate between • Structural and tissue changes of usually at or proximal to the place where pain is felt lumbar and nonlumbar tethering. pregnancy and postpartum. by the client. However, referral patterns are common Since the knee-up position • Direct trauma to the sciatic nerve, (typically involving gluteus maximus, medius, and decreases lumbar extension, suspect tumors or infections, or scarring or minimus; rotators; or hamstrings), and like other referred tethering at the lumbars (axial thickening of adjacent soft tissues. pain, these are sometimes unpredictable and aren’t easily explainable by direct neural connections. sciatica) if raising the knee on Some of the above causes suggest the passive side decreases pain. their own solutions, which often Use what you learn from involve changes in activities or performing the Sciatic Nerve Glide ergonomics. There are also many Test to choose where to work next. reports of appendicular sciatic relief being found in regular stretching (yoga’s Pigeon Pose or Eka Pada Kapotasana, in particular), or

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