A patient with a hip fracture is found to have an intact hip joint but later develops avascular necrosis of the femoral head. Which vessel is most commonly responsible for the blood supply to the femoral head that is disrupted?

• A Medial circumflex femoral artery (via retinacular arteries ascending along the femoral neck) ✓
• B Lateral circumflex femoral artery (ascending branch)
• C Artery of the ligamentum teres (foveal artery) alone
• D Obturator artery via the acetabulum

Explanation

The major blood supply to the femoral head in adults comes from the medial circumflex femoral artery (MCFA), which gives rise to retinacular arteries that ascend along the neck of the femur and pierce the head of the femur to supply it. The MCFA is a branch of the profunda femoris artery. Intracapsular femoral neck fractures disrupt these retinacular vessels (which run along the posterior femoral neck within the joint capsule), leading to avascular necrosis. The artery of the ligamentum teres supplies only the small foveal region and is insufficient to prevent AVN on its own.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.