A patient can feel severe discomfort when the sciatic nerve is pinched or pressed. A tingling feeling, a lack of sensation, deadness, and even frailty in the hip, buttock and leg can be symptoms witnessed. For under 60-year olds, the customary cause of sciatica is a herniated disc.
For older adults, the most likely source of sciatica is spinal stenosis which is a narrowing of the openings of the spine the nerves travel through, and spondylolisthesis, which is when one vertebra slides forward on the neighbouring vertebra.
The sciatic nerve is made up of five nerve roots that exit the spine in the lower back. They then merge into one nerve that travels through the buttock and down to the leg. At the back of the knee, the nerve divides into two nerves. These two nerves are the tibial and common peroneal, that travel into the inner and outer lower leg and foot.
In most instances, a nerve root moves freely in and out of the spine through holes located between each vertebra. Tthese are known as intervertebral foramen (IVF). Exercises such as hamstring stretches or kicking a rugby ball create resistance within the sciatic nerve and pull the nerve roots out of the IVFs. Likewise, when we stand upright and stare at our toes, this pulls the spinal cord upward and the nerve roots move into the IVFs.
When undertaking management of sciatica, osteopaths will make use of an approach named nerve flossing. Similarly, with flossing teeth, the forward and backwards movement of the dental floss is theoretically the same move as the back and forth motion of the five nerve roots, that combine into the sciatic nerve. To draw the nerve roots out of the IVF, extend the head and neck skyward and then bend the foot/ankle skyward in addition (toes toward the nose). To flex the nerve back into the IVF, aim the foot/ankle down while the head/neck flexes progressively (chin to chest). Replicate several times as long as pain or other symptoms are not exacerbated. The concept underlying this is to relieve the nerve root by minimising sticking in the IVF.
Nerve flossing is generally conducted by an osteopath to ensure it is well tolerated and safeguarded, so that the patient can carry out the movement at home multiple times a day. Studies suggest that this method helps minimise stress on the sciatic nerve whilst pulling on the hamstrings, which are invariably tight in patients with low back pain.