The sciatic nerve is composed of five nerve roots that exit the spine in the lower back (L4 to S3). The nerves then merge into one nerve that travels through the buttock and into the leg. Towards the back of the knee, the nerve divides into two nerves, the tibial and common peroneal. These two are nerves that travel into the inner and outer lower leg and foot.
When the sciatic nerve is compressed, a patient can feel pain, tingling, numbness, and weakness in the hip, buttock, and leg. For people before the age of 60, the most common cause of sciatica is a herniated disk. For adults above 60, the most likely causes of sciatica are spinal stenosis and spondylolisthesis.
A nerve root moves freely through the spine through holes located between each vertebra called intervertebral foramen (IVF). Movements and exercises such as hamstring stretching or punting a football create tension on the sciatic nerve. It pulls the nerve roots out of the intervertebral foramen. Similarly, when we stand up and look down at our feet, this pulls the spinal cord upward. The nerve roots then move into the IVFs.
Sciatica Treatment – Nerve Flossing
When managing sciatica, chiropractors utilize a technique called nerve flossing. Like flossing teeth, the back and forth motion of dental floss is similar to the back and forth motion of the five nerve roots that merge into the sciatic nerve. To pull the nerve roots out of the IVF, extend the head/neck up and then flex the foot/ankle upward as well (toes toward the nose). To pull the nerve into the IVF, point the foot/ankle down while the head/neck flexes forward (chin to chest). Repeat this a few times as long as pain or other symptoms don’t worsen. The concept behind this is to free up the nerve root by reducing adhesions in the IVF.
Nerve flossing is usually performed by a chiropractor to make sure it is well tolerated and safe so that the patient can perform the exercise at home throughout the day. Studies show that nerve flossing helps reduce tension on the sciatic nerve. Stretching the hamstrings can also help patients with low back pain.
