First, let us define what sciatica actually is and is not. Sciatica is, very specifically, pain along the sciatic nerve stemming from irritation of that nerve. The sciatic nerve is formed from a conglomeration of spinal nerves in the low back which binds together into one sheath. This nerve runs under the piriformis muscle in the pelvic area, then runs in between the two parts of the biceps femoris, also known as the hamstrings. It has become common to call any pain in the leg which is suspected to come from the back, sciatica. However, sciatica is a nerve pain which is the same feeling you get when you hit your “funny bone.” Most leg pain, and consequently what most people call sciatica, is actually referred pain. That is a different post. To be a true diagnosis of sciatica, it must be nerve pain that stems from the lumbar spine and runs into the buttock and/or down the backside and middle of the thigh. Now that we have that out of the way, let’s talk about what causes it!
- Disc Injury. Disc injuries are the most common back ailment. When a disc bulges or herniates, it can occupy the space where the spinal nerves exit from the vertebral column. If a disc bulges too far it can push against the nerve root causing pain to travel down the sciatic nerve and beyond. Sometimes, the bulge will hit the nerve and then pull back enough so that the sciatic pain is not constant. If the disc is in constant contact with the nerve, one can experience pain, numbness and tingling, weakness, and other symptoms. Chiropractic can help, but these can take a long time to heal and consistency makes the difference. Traction, rehabilitation exercises, physical therapy, and stretching can also help if done properly. If it comes to it, cortisone injections and surgery may be last resort options.
- Inflammation. With injury comes inflammation. Though the disc is the most common injury, there are several other structures in the area of the nerves that make the sciatic nerve that can be injured. Inflammation is toxic and can cause its own set of issues. Nerves are especially sensitive to inflammation. Icing, NSAIDs like ibuprofen, Chiropractic, and steroids can all help reduce inflammation. When the inflammation is in check, the back and sciatic pain will diminish. When the area with the sciatic nerve or nerve root is inflamed. The symptoms will remain constant.
- Sacro-Iliac (SI) Joint Dysfunction. The sciatic nerve crosses the SI Joint just after it forms the large nerve. If the pelvis shifts or is not working properly, it can irritate the Sciatic Nerve through direct pressure, inflammation, or by causing muscle tightness or spasms from the imbalance. Adjusting the SI joint will help reduce inflammation and muscle guarding, as well as move it away from contact with the nerve if that is the case. Chiropractic is by far the best thing for this case but a clever physical therapist can help, too. Exercise, stretching, and icing may help but can irritate it, as well.
- Piriformis Syndrome. This diagnosis has become pretty popular. I find that it is misdiagnosed more often than not. The piriformis is a little pear-shaped muscle (hence the name, piri means pear), that spans the SI joint. The Sciatic Nerve runs underneath it in most individuals. If this muscle tightens, it can compress the sciatic nerve and cause sciatica. The piriformis can tighten for various reasons including any of the above-mentioned maladies. Usually, I find the piriformis is a secondary issue. Sometimes, however, it can take on a life of its own after the other condition has resolved. If it is, truly, piriformis syndrome, the best thing to do is have a specialist perform a muscle release on it. Active release, myofascial release, Bowen, Rolfing, massage, etc. can all help if done right. Be aware that if it only helps for a little while, then there is probably another issue that is still causing the muscle to tighten or guard.
- Direct Contact. Because the Sciatic Nerve runs through the buttock and down the back of the leg, the way one sits can cause sciatica. The most common cause is a wallet in the back pocket. Additionally, a seat that curves upward along its lip can put pressure on the legs and irritate the nerve. Unfortunately, I have seen this most often in vehicles. The solution for these is obvious. The trick is to figure it out before it causes problems more difficult to remedy.
There you have it. Probably not a comprehensive list but definitely the most common causes. Sciatica is actually rarer than it seems. When you have it, however, it is very painful and can be difficult to treat. If you are experiencing sciatica or any type of pain or other symptoms down the leg, chiropractic can help. And, like all conditions, being prompt and consistent makes for better and quicker healing.