Advanced Tibial Nerve Quiz

Q1. Why can a proximal tibial nerve lesion markedly weaken plantarflexion?

• Plantarflexion is produced primarily by quadriceps
• The lesion affects only cutaneous fibers
• It interrupts motor supply to major posterior compartment plantarflexors
• Plantarflexors are supplied mainly by the deep fibular nerve

Q2. Which finding helps distinguish a tibial neuropathy from a common fibular neuropathy?

• Foot drop with preserved plantarflexion
• First dorsal web space numbness alone
• Weak eversion with normal toe flexion
• Weak plantarflexion and toe flexion

Q3. Why can tarsal tunnel syndrome produce plantar sensory symptoms without major calf weakness?

• Calf muscles are supplied by the femoral nerve
• The tarsal tunnel lies proximal to the popliteal fossa
• The tibial nerve becomes purely motor at the ankle
• The major calf motor branches arise proximal to the tarsal tunnel

Q4. Which symptom distribution is most consistent with tibial nerve compression in the tarsal tunnel?

• Medial thigh numbness with adductor weakness
• Pain or paresthesia involving the plantar foot
• Numbness isolated to the first dorsal web space
• Lateral thigh burning only

Q5. Why may heel sensation vary in tarsal tunnel syndrome?

• Calcaneal branches have variable origins relative to the tunnel
• Heel skin is supplied only by the femoral nerve
• The tibial nerve never supplies the heel
• All calcaneal branches arise from the deep fibular nerve

Q6. Which deficit suggests a tibial nerve lesion proximal to branches supplying the deep posterior compartment?

• Weak knee extension with hip flexion
• Weak toe extension with foot eversion
• Weak hip abduction with pelvic drop
• Weak toe flexion with weakened inversion

Q7. Why can a severe tibial nerve lesion impair push-off during gait?

• Loss of plantarflexor power reduces propulsion in late stance
• Loss of hip abductors directly eliminates toe flexion
• Loss of dorsiflexors prevents heel rise
• Loss of quadriceps prevents ankle inversion

Q8. Which relationship is important when locating the tibial nerve behind the medial malleolus?

• It lies beneath the flexor retinaculum with posterior tibial vessels and flexor tendons
• It winds around the fibular neck
• It passes through the adductor hiatus
• It lies superficial to the extensor retinaculum

Q9. Why can a tibial nerve lesion proximal to the ankle affect intrinsic foot muscles?

• Intrinsic foot muscles are supplied only by the superficial fibular nerve
• Intrinsic foot muscles receive only femoral innervation
• The tibial nerve becomes sensory below the knee
• The tibial nerve contains motor fibers that continue into both plantar nerves

Q10. Which statement best integrates tibial nerve anatomy?

• It is an L2-L4 femoral branch supplying the anterior thigh
• It is an S2-S4 gluteal branch supplying gluteus maximus
• It is an L5-S2 posterior-division branch supplying the lateral leg and dorsal foot
• It is an L4-S3 sciatic component that supplies the posterior leg and continues as the plantar nerves