Pain Getting on Your Last Nerve?

November 9, 2009 | by Dr. Jess

If yes and you’ve tried everything with the exception of bloodletting to fix the pain, then you may be barking up the wrong tree. There are many causes of pain and it’s your practitioners job to identify the site of pain and then (what may be even more challenging) determine the cause. What some of you may not know, a strained muscle may actually be an entrapped nerve that is getting snagged everytime you move. Let’s take a common entrapment I see daily in the office. The Sciatic Nerve Entrapment. The Sciatic Nerve is a very large nerve that forms from spinal nerves emerging from the low back and sacrum and then travels through the gluteal muscles, through the hamstrings and adductors, then splits into the Tibial Nerve (which runs the back of the calf and bottom of the foot) and the Peroneal Nerves (which wrap around to the front of the shin and foot). For those of you who have herniated a disc in your low back (L4/5 or L5/S1) know all too well the path of the sciatic nerve as you have probably gotten zapping, traceable pain down the back of the leg as well as tingling or numbness in the foot or toes. The Sciatic Nerve (as well as the Tibial and Peroneal Nerves) can become entrapped anywhere they pass through or adjacent to muscles by scar tissue. There are many reasons entrapments happen. They can be due to repetitive motion, sitting too long, poor posture, injury and inflammation, etc. As a practitioner, we address these entrapments using Active Release Techniques (ART®) to trap the muscle with our hand or fingers while we “pull” the nerve through the entrapment using the patient’s own body movements. Of course, we don’t address the cause as well, the entrapment can come right back. However, I’d like you to think of a common complication I see with nerve entrapments and even disc herniations pressing on the spinal nerve. It’s the thoracic spine. The thoracic spine starts at the base of your neck and then all the way down to where your low back starts to change it’s curve and sway. If you work seated for most of the day, then there’s a good chance you sit with a kyphotic posture. Meaning you have a “C” curve where you have a perfectly rounded back from the base of your neck that forms a “C” all the way to your sit bone. (Your head is probably translated forward as well.) And not only do you have this kyphotic posture, more importantly your thoracic spine is probably restricted in extension. Meaning you can’t bend backwards in your thoracic spine. You may compensate in your low back and neck (this is a topic for another blog- restricted Thoracic spine causing pain in the neck, back, shoulders, and hips…) by extending more there, but not the midback. Well, what’s the problem? Think of a rope (spinal cord) that’s in a flexible tube (spinal column) and that rope is not touching any part of the tube. It is suspended in the tube which is good because it has room to move when the tube moves. Even though the spinal cord can actually stretch a little, let’s say it’s negligible and therefore it’s a very stiff rope. Now picture the tube bending and flexing into a “C” curve. The rope will now actually touch a side of the tube and will “shrink” from the bottom and the top in order to follow the shape of the “C” curve. Now picture at the bottom or top (and in some people both) the rope is stuck. Now try to move the tube into a “C” curve. What happens? Well, we could have the rope “shrink” more from one end. We could have a really big SNAG on the area that’s stuck. Or both. And more importantly, that rope is compressed even more onto the side of the tube. So, if someone is stuck in a kyphotic posture and they can’t extend in the thoracic spine very well, an entrapped nerve can become symptomatic because it’s getting snagged even more when the athlete tries to move. OR when they sit in a kyphotic posture for long periods of time. Here’s an example: We commonly see patients with chronic hamstring tightness and strains. I have a physical therapist friend who lives in the Cayman Islands and has a thriving sports medicine practice. She emailed me about one of her patient’s chronic hamstring spasms everytime he dives using flippers and also with running. We know that hamstring spasms can occur from weak gluteal muscles and poor lumbopelvic stability. (The glutes become inactive due to the poor lumbopelvic stability and thus the hamstrings have to do all the work.) They tried strengthening and stabilization exercises, soft tissue treatments, mobilization, etc. and he still had the chronic spasms. Since she’s done all the necessary treatments and still had issues, I went straight to what may seem like an unlikely candidate, the sciatic nerve. I introduced her to David Butler, PT who was basically the pioneer on nerve gliding and then explained an exercise to mobilize the thoracic spine and spinal cord in case he had any nerve entrapments along the spine as well as restricition in the thoracic spine. She gave him the exercise and said when he showed up for his appointment the following week he ran to her and gave her a big hug as he finally was able to dive without hamstring spasms.