Sciatica

What is Sciatica?

Sciatica is compression of the Sciatic nerve which is formed of spinal nerve roots L4 to S3 and travels beneath the Piriformis muscle and down the back of the thigh to the popliteal fossa behind the knee.

Causes:

Compression of the Sciatic nerve may occur through over contraction of the Piriformis muscle (Piriformis syndrome) as it travels beneath it on its path through the buttock.

Compression of one or more of the spinal nerve roots that form the Sciatic nerve may occur through disc bulge, prolpase or herniation, spinal stanosis or spondylolisthesis.

Symptoms:

Compression or irritation of one or more of the nerve roots that supply the Sciatic nerve causes neurological symptoms such as back pain, leg pain, tingling, burning sensation and muscle contraction and weakness in the dermatomes and myotomes of the effected nerve roots.

A dermatome is an area of skin supplied by a nerve root.

A myotome is a muscle supplied by a nerve root.

Treatment: Compression of the Sciatic nerve

Red Flags: Cauda equina syndrome: Immediate consultant referral and further investigation is essential if symptoms include: Loss of bowel or bladder control /incontinence and/or saddle anesthesia (a loss of sensation in an area as if sitting on a saddle).