Femoral Artery

Introduction

Introduction to the Femoral Artery

The femoral artery is the principal arterial supply to the lower limb. It is the direct continuation of the external iliac artery distal to the inguinal ligament. The vessel traverses the femoral triangle, enters the adductor canal, and becomes the popliteal artery as it passes through the adductor hiatus. Its superficial position in the femoral triangle makes it accessible for pulse palpation, catheterisation, and angiography, while its deep course in the adductor canal places it at risk in femoral shaft fractures and surgical procedures. The femoral artery and its largest branch, the profunda femoris artery, supply the anterior, medial, and lateral compartments of the thigh.

Study

1. Origin and Course

The femoral artery begins at the mid‑inguinal point, halfway between the anterior superior iliac spine (ASIS) and the pubic symphysis, deep to the inguinal ligament. It descends within the femoral sheath in the femoral triangle, lying lateral to the femoral vein and medial to the femoral nerve. At the apex of the femoral triangle, it enters the adductor canal (Hunter’s canal) together with the femoral vein and saphenous nerve. The canal is formed by the vastus medialis laterally, the adductor longus and magnus posteriorly, and the sartorius and its subsartorial fascia anteriorly. The femoral artery exits the adductor canal through the adductor hiatus, a gap in the tendon of adductor magnus, to become the popliteal artery.

2. Branches of the Femoral Artery

Within the femoral triangle, the femoral artery gives off three superficial branches and one large deep branch. The superficial branches are the superficial epigastric artery (ascending onto the anterior abdominal wall), the superficial circumflex iliac artery (running laterally along the inguinal ligament), and the superficial external pudendal artery (passing medially to the external genitalia). The deep external pudendal artery also arises, piercing the cribriform fascia. The largest and most important branch is the profunda femoris artery (deep artery of the thigh), which arises from the posterolateral aspect of the femoral artery, approximately 3.5–4 cm distal to the inguinal ligament. The profunda femoris gives off the medial and lateral circumflex femoral arteries and perforating branches that supply the thigh muscles. In the adductor canal, the femoral artery gives off the descending genicular artery, which contributes to the genicular anastomosis of the knee.

3. Relations within the Femoral Triangle

The femoral artery lies lateral to the femoral vein within the femoral sheath. The femoral nerve lies lateral to the sheath, not enclosed within it. The medial compartment of the femoral sheath is the femoral canal, which contains lymphatic vessels and the deep inguinal lymph node (Cloquet’s node). The artery is anteriorly covered by skin, superficial fascia, deep fascia (fascia lata), and the femoral sheath. Posteriorly, it rests on the psoas major tendon, pectineus, and adductor longus muscles. The great saphenous vein pierces the cribriform fascia to join the femoral vein at the saphenofemoral junction.

4. Clinical Surface Anatomy

The femoral pulse is palpable at the mid‑inguinal point, immediately below the inguinal ligament. This site is used for femoral artery cannulation, angiography, and blood gas sampling. The artery can be compressed against the superior pubic ramus and femoral head to control distal haemorrhage. A line from the mid‑inguinal point to the adductor tubercle represents the surface marking of the femoral artery.

5. Clinical Relevance

Femoral artery catheterisation is a common interventional procedure. Complications include pseudoaneurysm, arteriovenous fistula, and retroperitoneal haematoma if the puncture is above the inguinal ligament. Femoral artery injury can occur in penetrating trauma, femoral shaft fractures, or hip surgery. Acute occlusion is a surgical emergency due to the risk of limb loss. The profunda femoris artery provides a crucial collateral circulation around the hip, and stenosis of the superficial femoral artery can be bypassed. Peripheral arterial disease (PAD) frequently affects the superficial femoral artery in the adductor canal. The femoral artery is also used in coronary artery bypass grafting as a conduit (radial artery is more common now).

Summary

Summary of the Femoral Artery

The femoral artery is the main arterial supply to the lower limb. It runs from the inguinal ligament to the adductor hiatus. In the femoral triangle it gives the superficial branches and the profunda femoris artery. Within the adductor canal it gives the descending genicular artery. Its superficial location allows for access and palpation, while its deep course in the adductor canal makes it vulnerable to trauma. The profunda femoris is the main supply to the thigh muscles.