Lower Extremity Nerves

Question 1

Obturator (L2-L4)

Answer 1

Cause of injury: Anterior hip dislocation
Motor deficit: Thigh adduction
Sensory deficit: Medial thigh

Question 2

Femoral (L2-L4)

Answer 2

Cause of injury: Pelvic fracture
Motor deficit: Thigh flexion and leg extension
Sensory deficit: Anterior thigh and medial leg

Question 3

Common peroneal (L4-S2)

Answer 3

Cause of injury: Trauma or compression of lateral aspect of leg or fibula neck fracture
Motor deficit: Foot eversion and dorsiflexion; toe extension; foot drop, foot slap, steppage gait
Sensory deficit: Anterolateral leg and dorsal aspect of foot

Question 4

Tibial (L4-S3)

Answer 4

Cause of injury: Knee trauma
Motor deficit: Foot inversion and plantarflexion; toe flexion
Sensory deficit: Sole of foot

Question 5

Superior gluteal (L4-S1)

Answer 5

Cause of injury: Posterior hip dislocation or polio
Motor deficit: Thigh abduction (positive Trendelenburg sign-contralateral hip drops when standing on leg ipsilateral to site of lesion)
Sensory deficit:

Question 6

Inferior gluteal (L5-S2)

Answer 6

Cause of injury: Posterior hip dislocation
Motor deficit: Can’t jump, climb stairs, or rise from seated position; can’t push inferiorly (downward)
Sensory deficit: