Skip to main content
OrthoVellum
Knowledge Hub

Study

  • Topics
  • MCQs
  • ISAWE
  • Operative Surgery
  • Flashcards

Company

  • About Us
  • Editorial Policy
  • Contact
  • FAQ
  • Blog

Legal

  • Terms of Service
  • Privacy Policy
  • Cookie Policy
  • Medical Disclaimer
  • Copyright & DMCA
  • Refund Policy

Support

  • Help Center
  • Accessibility
  • Report an Issue
OrthoVellum

© 2026 OrthoVellum. For educational purposes only.

Not affiliated with the Royal Australasian College of Surgeons.

Basic Science
intermediate
X-Type

Sciatic Nerve Anatomy - Tibial and Peroneal Divisions

Peripheral Nerve Anatomy

A 45-year-old man undergoes total hip arthroplasty through a posterior approach. Post-operatively, he has a foot drop with inability to dorsiflex his ankle or extend his toes. Sensation is diminished over the dorsum of his foot and lateral leg. His ankle jerk reflex is intact and he can plantarflex his ankle normally. The surgeon is concerned about intraoperative sciatic nerve injury. Regarding sciatic nerve anatomy and its clinical implications:

Mark each as TRUE or FALSE

A

The sciatic nerve is derived from L4-S3 nerve roots and exits the pelvis through the greater sciatic...

B

The common peroneal (fibular) division is lateral, more superficial, and more susceptible to injury ...

C

The sciatic nerve exits superior to piriformis in all anatomical variants; the common peroneal nerve...

D

The common peroneal nerve supplies ankle dorsiflexion (tibialis anterior L4-5), toe extension (EHL, ...

E

The tibial nerve supplies ankle plantarflexion (gastrocnemius, soleus), toe flexion (FHL, FDL), and ...

Answer the questions to see explanations

Click T (True) or F (False) for each option