# Femoral Triangle Anatomy

How the femoral triangle at the top of the thigh is built, showing the nerve, artery and vein passing through it and the fascia iliaca beneath\.

By Arun

Topic: Human Body & Medicine

[Open the interactive Jig](https://ask.jig.com/j/lfWr0kWs36Jj)

## Transcript

### 1. A crossroads at the top of the leg

Where your thigh meets your body there is a small hollow called the femoral triangle\. Three important cords pass through it: a nerve, an artery and a vein\. This model shows the right leg from the front, about three times life size\.

Drag the model to turn it\. Scroll or pinch to move closer\.

### 2. The edges of the triangle

The top edge is the inguinal ligament, a tough band from the hip bone to the pubic bone\. The sides are two strap\-shaped muscles: sartorius on the outside and adductor longus on the inside\. The triangle points down the thigh\.

Sartorius is the longest muscle in the body\.

### 3. Nerve, artery, vein

From the outside of the leg inwards, the order is always the same: nerve, artery, vein\. Just inside the vein is a small gap holding lymph vessels and a lymph node\.

Remember NAVL: Nerve, Artery, Vein, Lymph, from the outside in\.

### 4. The artery

The femoral artery carries bright red, oxygen\-rich blood from the heart down the leg\. It is about as wide as a pencil, roughly 6 to 10 millimetres\. A little way down, it sends a big branch deep into the thigh\.

You can feel its pulse in the crease of your groin\.

### 5. The vein

The femoral vein lies on the inner side of the artery and carries blood back up to the heart\. Its wall is thinner, so it is softer and a little wider\. Lower down, it tucks in behind the artery\.

The great saphenous vein, the long vein of the leg, joins it here\.

### 6. The fascia iliaca

Over the hip muscles lies the fascia iliaca, a thin, shiny sheet of tough tissue\. The artery and vein lie in front of it\. The femoral nerve runs behind it, in a groove between two muscles\.

Fascia \(say FASH\-ee\-uh\) is the wrapping tissue around muscles\. Lift the sheet away to see the nerve\.

### 7. Slice across

Cut across the model and the layers become clear\. The artery and vein sit in front of the sheet\. The nerve lies behind it, on the muscle\. Move the slice up and down the triangle\.

The nerve is usually 2 to 4 centimetres under the skin\.

### 8. Why the sheet matters

Because the nerve lies under the fascia iliaca, doctors can use the sheet as a guide\. To ease the pain of a broken hip, they can slide numbing medicine under it, beside the artery\. The medicine spreads along the sheet and reaches the nerve\.

About 20 to 40 millilitres, a few spoonfuls, is enough\.

### 9. Your femoral triangle

Nerve on the outside, then artery, then vein, with the fascia iliaca keeping the nerve apart\. Pick one to make it stand out, and turn the model to see it from every side\.