Which of the following nerves is not directly linked to the L2`"L3 spinal level?

The correct answer is A. Tibial. Tibial nerve (A) arises from the sacral plexus (L4–S3), making it the nerve with no direct origin at L2–L3. The femoral nerve (C) is incorrect as a distractor because it originates from L2–L4, with L2 and L3 being core contributors responsible for hip flexion and knee…

Normal Structure and Function

Question

Options

ATibial
BObturator
CFemoral

How the community answered

(33 responses)

A
82% (27)
B
6% (2)
C
12% (4)

Explanation

Tibial nerve (A) arises from the sacral plexus (L4–S3), making it the nerve with no direct origin at L2–L3. The femoral nerve (C) is incorrect as a distractor because it originates from L2–L4, with L2 and L3 being core contributors responsible for hip flexion and knee extension. The obturator nerve (B) is likewise directly rooted at L2–L4, running through the obturator foramen to innervate the medial thigh adductors. A useful memory tip: "FOO stays high, Tibial goes low" - Femoral and Obturator nerves originate in the lumbar plexus (L2–L4), while the Tibial nerve is a branch of the sciatic nerve and belongs to the sacral plexus, well below L3.

Topics

#nerve plexuses#spinal nerve levels#peripheral nerve anatomy#lower extremity

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