Sciatica and Piriformis Syndrome

spinal stenosis

One of the more common injuries seen in chiropractic offices around the country is sciatica. Those of us unlucky enough to have dealt with this injury in the past fully understand how painful it can be and how much havoc it can cause in your life. Sciatica has a lot of fancy names like sciatic neuralgia, sciatic neuritis, and lumbo-sacral radiculitis but no matter what you call it it is defined by pain in the buttock and leg. If you break down its fancy names you will see that it results from the inflammation of the sciatic nerve. This inflammation can be the result of direct trauma, compression, or decreased blood flow (ischemia) to the sciatic nerve. Compression of the sciatic nerve, the most common cause that I see in my office, generally occurs either at the spine where the nerve exits the spinal column or somewhere along the nerve as it descends the leg. Compression at the spine is usually the direct result of a disc herniation, bulging disc, foreign body, or the narrowing of the canal that it exits the spine through, which is called stenosis. Stenosis usually occurs because of arthritis, disc degeneration, bone spurs, or abnormal growth of ligament or bone called hyperplasia. It is also important to note that a very common cause of ischemia to the sciatic nerve is by direct compression by a bulky wallet in the back pocket of your pants so make sure to get that wallet out of there while driving or sitting for long periods. I cannot even count how many cases I have resolved by that simple change. Now, when it comes down to peripheral nerve entrapment, the most common structure to compress the sciatic nerve is the piriformis muscle. This small muscle that runs across the top of the buttock from the pelvis to the side of the hip can go into spasm and compress the sciatic nerve, causing sciatica. The sciatic nerve passes directly under the piriformis muscle and in 12% of the population it actually pierces through the middle of the muscle. This specific form of sciatica is called piriformis syndrome and in this article I will discuss its presentation, causes, and treatments.

Sciatic nerve neuritis caused by the contracture of the piriformis is one of the most common peripheral nerve entrapments in the body and is also one of the most misdiagnosed entrapments as well. Many doctors just assume that cases of sciatica are caused by disc bulges and herniation and order MRI's to diagnose the condition. These same doctors are confused when the MRI shows no sign of arthritis or disc displacement. EMG tests will have mixed results but for the most part the lower gluteal and lower limb muscles will be abnormal but the large paraspinal muscles in the lower back will be normal, as will the TFL. Piriformis syndrome will have many signs and symptoms in common with traditional sciatica including pain down the buttock and lateral leg, numbness, pain with forward bending, leg weakness, and decreased range of motion in the low back and leg. Both with have positive orthopedic tests like the Straight Leg Raise Test. Valsalva Test will be negative if there is no disc involvement but remember that piriformis syndrome can coexist with a disc injury. The piriformis muscle's normal action is to externally rotate the leg which means it opens the foot outward as if you were going to kick a soccer ball with the instep of your foot. With that in mind, signs that the piriformis muscle is contracted include one-sided toeing out when standing or walking, increased pain with internal rotation of the leg, and pain with stretching the piriformis muscle. The way to isolate and stretch the piriformis muscle is to sit in a chair, cross and flatten the leg (like a man crosses his leg), and lean forward and to the side towards the crossed foot.

There is a lot you can do at home for treatment before going into your doctor's office. Massage and trigger point work at the origin and insertion of the piriformis muscle is very effective. Ice therapy in the area of the upper buttock along with stretching can also calm down an inflamed case of sciatica. Stretching the piriformis muscle as described above in the seated position with the affected leg crossed can help to lengthen the contracted muscle. Other muscles that should be stretched include the hamstring muscle, TFL, and glut medius. Lifestyle changes include avoiding long periods of sitting, beginning a light walking routine, and drinking lots of water to keep your muscles from cramping. If the condition does not improve within 2 weeks it is recommended that you see a specialist. Chiropractors are trained to diagnose and treat these conditions and will typically incorporate myofascial release, post isometric relaxation stretching, therapeutic ultrasound, electric muscle stimulation, and chiropractic manipulations to complement the above mentioned home treatments. In more severe cases you may need to see a neurologist or orthopedist. It is important to remember that prolonged ischemia or compression to the sciatic nerve can cause major damage to the nerve so it is recommended that you seek medical help if the condition lasts longer than 2 weeks.