Sural nerve (S1–S2)

Terminal branches · S1 S2

Purely sensory nerve formed in the calf when the medial sural cutaneous nerve (tibial) is joined by the sural communicating branch from the lateral sural cutaneous nerve (common fibular). Descends with the small saphenous vein, passes behind the lateral malleolus and runs along the lateral border of the foot.

Traced from the start

  1. L4 anterior ramusL5 anterior ramus
  2. S1 anterior ramusS2 anterior ramusS3 anterior ramusS4 anterior ramus
  3. Lumbosacral trunk (L4–L5)Sacral plexus anterior divisionsSacral plexus posterior divisions
  4. Sciatic nerve (L4–S3)
  5. Tibial nerve (L4–S3)Common fibular (peroneal) nerve (L4–S2)
  6. Sural nerve (S1–S2)

Detail

Motor
None
Sensory
Posterolateral distal leg, lateral heel and ankle, lateral border of the foot and little toe
Companion
Small (short) saphenous vein
Uses
Standard site for diagnostic nerve biopsy (peripheral neuropathy, vasculitis) and for nerve grafts

When it goes wrong

Injury during small saphenous vein surgery, Achilles tendon repair or lateral ankle surgery; or deliberately excised for biopsy

Numbness of the lateral foot and little toe only, with no motor loss

Practise this structure

1 question in the bank tagged Sensory Territory.