Types of sciatica

Sciatica is not a single condition. Doctors describe different types based on the cause, the duration and the nerve root involved. Knowing the type helps decide whether rest, exercise, medicine, injections or surgery is likely to help.

By duration

• Acute sciatica: lasts up to about four weeks. Most people recover with simple care.
• Subacute: lasts four to twelve weeks.
• Chronic sciatica: lasts more than twelve weeks and needs a thorough assessment.

By pattern

• Unilateral sciatica: pain on one side, the most common.
• Bilateral sciatica: both legs affected. This is less common and may signal a more serious spinal problem such as stenosis or a large central disc herniation.
• Alternating sciatica: pain switching between sides, often linked to the sacroiliac joint.
• Intermittent sciatica: pain that comes and goes.

By nerve root

• L4 and L5 roots: pain in the outer thigh and shin, numbness in the top of the foot and weakness in lifting the foot or big toe.
• S1 root: pain in the calf and the sole, and weakness pushing the foot down.

By cause

• Disc-related sciatica from a herniated disc.
• Stenosis-related sciatica, with pain when walking that eases when sitting.
• Piriformis or deep gluteal syndrome from buttock muscle pressure.