Sciatica

Sciatica is a layman’s term for a pinched nerve that can cause pain that runs from the buttocks down the back of the leg.  When people commonly refer to sciatica it is not necessarily a problem of the sciatic nerve.  It’s a problem of the nerve when it is being pinched as it exits from the spine from a herniated disc or a bone spur.

Sciatica is a form of peripheral neuropathy.  It occurs when there is damage to the sciatic nerve located in the back of the leg.  This nerve controls the muscles of the back of the knee and lower leg and provides sensation to the back of the thigh, part of the lower leg and the sole of the foot.  Irritation of the sciaitic nerve can occur where it exits the spine or anywhere along its course down through the leg.

Sciatica is primarily caused by pressure on a nerve from a herniated disc or bone spur (also referred to as a ruptured disc, bulging disc, slipped disk, etc.).  A herniated lumbar disc in the spine may cause symptoms that simulate the symptoms of sciatic nerve dysfunction.

The sciatic nerve can also be injured by fractures of the pelvis or other trauma to the buttocks or thigh.  Prolonged sitting or lying with pressure on the buttocks may also injure it.  Systemic diseases, such as diabetes, can typically damage many different nerves, including the sciatic nerve. 

 The sciatic nerve may also be harmed by pressure from masses such as a tumor or abscess, or by bleeding in the pelvis.