A tibial plateau fracture extending laterally places risk on which nerve?

• A. Common peroneal nerve
• B. Tibial nerve
• C. Sciatic nerve only
• D. Obturator nerve

Answer: (A)

The key idea is the anatomy of the knee’s lateral aspect. The common peroneal nerve branches from the sciatic and courses around the fibular neck right near the lateral knee. A tibial plateau fracture that extends laterally puts direct stress or potential laceration on this nerve as it runs just distal to the lateral aspect of the proximal tibia and around the fibular head. Because of its superficial and exposed path at the fibular neck, it is the nerve most at risk with lateral knee injuries like this one. In contrast, the tibial nerve lies medially in the popliteal region and is less likely to be affected by a lateral plateau fracture, and the obturator or sciatic nerves are located further away from this fracture pattern. This is why the common peroneal nerve is the best answer.