Which artery is the major blood supplier to the head of the femur in adults?

• A. Lateral femoral circumflex
• B. Medial femoral circumflex
• C. Obturator
• D. Popliteal

Answer: (B)

In adults, the head of the femur gets its main blood supply from the retinacular arteries that accompany the medial femoral circumflex artery as it runs along the femoral neck into the head. These vessels form the primary vascular supply to the femoral head, which is why damage to them—such as from a femoral neck fracture—can lead to avascular necrosis. The lateral femoral circumflex artery mainly supplies the neck and anterolateral structures and is not the major source for the head. The obturator artery contributes to the acetabular and joint capsule region, with only a small contribution to the head via the artery to the ligamentum teres in adults. The popliteal artery does not reach the hip to supply the head. Therefore, the major supplier to the head of the femur in adults is the medial femoral circumflex artery.