Lower Limb Dermatomes and Myotomes

Question 1

Lower limb dermatomes

Answer 1

L1 - inguinal ligament
L2 -  lateral thigh
L3 - medial thigh
L4 - knees + big toe
L5 - lateral leg + middle 3 toes

S1 - lateral lower leg + little toe
S2 - popliteal fossa
S3 - horizontal gluteal crease
S4-5 - perianal

Question 2

Which set of nerves innervates the lower extremities

Answer 2

Lumbosacral plexus

-T2-S1

Question 3

Key lower limb myotomes

• hip flexion and extension
• knee extension and flexion
• ankle extension and flexion

Answer 3

Hip
FE L23, 45

Knee
EF L34, 51

Ankle
EF L45, S12