A 40-year-old man sustains a knee dislocation after a high-velocity MVA. On examination, both cruciate ligaments and the posterolateral corner (PLC) are disrupted. The vascular structure most at risk in posterior knee dislocation is:

• A Anterior tibial artery
• B Popliteal artery ✓
• C Common peroneal nerve
• D Posterior tibial artery

Explanation

The popliteal artery is tethered at the knee by the adductor hiatus proximally and the fibrous arch of soleus distally, making it exceptionally vulnerable to injury with knee dislocation — vascular injury occurs in 30–40% of posterior knee dislocations. Absent distal pulses or ankle-brachial index <0.9 mandates urgent CTA or surgical exploration. Even with apparently normal pulses, intimal tear causing delayed occlusion can occur, so close monitoring for 24–48 hours is required. Common peroneal nerve injury is also common in posterolateral dislocations (presenting as foot drop).

Reference: Maheshwari Essential Orthopaedics, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.