Final answer:
Blood supply to the femoral head and neck comes from the lateral circumflex artery, a branch of the deep femoral artery, with the blood being drained by the femoral vein.
Step-by-step explanation:
The blood supply to the femoral head and neck primarily comes from the branches of the deep femoral artery, with a significant contribution from the lateral circumflex artery, which is a branch of the deep femoral artery. The femoral artery, after passing the inguinal ligament, gives rise to several smaller branches, among which is the lateral deep femoral artery, leading to the laterally sited lateral circumflex artery. These vessels are crucial as they supply blood to the deep muscles of the thigh, the femoral head and neck, and other structures in the femoral region before the blood is eventually drained back into the femoral vein.