A patient sustains a posterior dislocation of the hip and subsequently develops loss of dorsiflexion and eversion of the foot, with preserved knee flexion and plantar flexion. The nerve injured is:

• A Common peroneal (fibular) nerve ✓
• B Tibial nerve
• C Superior gluteal nerve
• D Femoral nerve

Explanation

The common peroneal (fibular) nerve is the most frequently injured nerve in posterior hip dislocation because it wraps around the fibular neck laterally and its fibres run close to the posterior capsule. Loss of dorsiflexion (deep peroneal nerve — anterior compartment) and eversion (superficial peroneal nerve — lateral compartment) with footdrop characterises a common peroneal nerve lesion. Tibial nerve injury would abolish plantar flexion and inversion; superior gluteal nerve injury causes Trendelenburg gait without foot problems.

Reference: BD Chaurasia's Human Anatomy, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.