What is Sciatica?
Sciatica generally is a term used to describe symptoms of leg pain, and altered sensations including tingling, numbness and lower limb weakness. This is caused when the sciatic nerve becomes compressed or irritated.
The Sciatic nerve is the largest nerve in the body. It originates in our lumbar spine where it extends through the gluteal (buttock) area into our lower limb. It will then divide into two branches at our knee and will end in the foot.
Causes of Sciatica
Degenerative disc disease – reduces the disc height and therefore the space between the segments of the spine
Herniated (slipped) disc – will place pressure on the disc, associated inflammation that occurs with this injury will also irritate the nerve
Trauma/muscle spasm – will put pressure on the nerve that may refer along its distribution
Spinal Stenosis – narrowing of the spinal canal
Spondylolisthesis – when one of the vertebral body’s slips forward over the one below causing pinching of the nerve
Symptoms of Sciatica:
Pain in the lumbar spine or buttock, it may continue down the back of the thigh into the lower leg and foot
A sharp burning sensation down the back of the leg along the distribution of the sciatic nerve
Altered sensations including pins and needles, numbness and tingling in the lower limb
Aggravation of symptoms with repeated bending activities, and also during positional changes, ie: turning in bed, sitting – standing
Symptoms may become more intense when coughing and sneezing
Other symptoms seen may vary on the level at which the nerve root has been compressed.
L4 root compression: Symptoms usually felt in front of thigh and extend into the inside of the foot. Weakness in straightening the knee and also may have an altered knee-jerk reflex.
L5 root compression: Symptoms may extend to the ankle and foot. Altered sensations may be felt in this sole of the foot. There may be a weakness in the foot – and a foot drop may be seen.
S1 root compression: Symptoms may be felt in the outer border of the foot. Ankle-jerk reflex may be altered. Difficulty lifting your heel off the ground.