Anatomy · Lower Limb

Sciatic nerve: course, branches and applied anatomy

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  • Sciatic nerve: thickest nerve in the body, about 1.5 to 2 cm wide at its origin.
  • Formed by the tibial part and common peroneal part, arising from the sacral plexus.

Formation, Extent and Root Value

  • Tibial part: ventral divisions of the anterior primary rami of L4, L5, S1, S2, S3.
  • Common peroneal part: dorsal divisions of the anterior primary rami of L4, L5, S1, S2.
  • The two parts are usually enclosed in a common sheath of connective tissue.
  • Extent: begins in the pelvis, ends at or just above the superior angle of the popliteal fossa by dividing into tibial and common peroneal nerves.
  • Termination point is approximately at the junction of the upper two-third and lower one-third of the back of the thigh.

Course