The leg bones (primarily the femur, tibia, and fibula) receive their blood supply from a network of arteries, including branches of the femoral artery, popliteal artery, and their periosteal and nutrient arteries.
Here's a breakdown:
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Femur (Thigh Bone): The femur's blood supply is complex and derives from several sources:
- Nutrient Artery: The primary blood supply for the femoral shaft. It enters the bone through the nutrient foramen.
- Periosteal Arteries: These are small arteries that supply the outer layer (periosteum) of the bone and contribute to the blood supply of the cortex. These are derived from surrounding muscles' blood vessels.
- Metaphyseal and Epiphyseal Arteries: These arteries supply the ends (metaphyses and epiphyses) of the femur, particularly important during growth. Branches from the femoral and popliteal arteries contribute.
- Arteries around the Hip Joint: Branches from the femoral circumflex arteries (medial and lateral) provide crucial blood flow to the femoral head and neck. Disruption of these vessels (e.g., femoral neck fracture) can lead to avascular necrosis.
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Tibia (Shin Bone):
- Nutrient Artery: A major supplier to the tibial shaft, entering the bone at the level of the soleus muscle attachment.
- Anterior Tibial Artery: This artery and its branches supply the anterior compartment muscles of the leg and also contribute to the periosteal blood supply of the tibia.
- Posterior Tibial Artery: Provides blood supply to the posterior compartment muscles and gives off branches that contribute to the periosteal supply. It also contributes to the nutrient supply of the fibula.
- Fibular (Peroneal) Artery: A branch of the posterior tibial artery, it runs along the fibula and contributes to its blood supply and the supply to the lateral compartment muscles.
- Metaphyseal and Epiphyseal Arteries: Derived from the anterior and posterior tibial arteries and the fibular artery, they supply the ends of the tibia and fibula.
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Fibula (Lateral Leg Bone):
- Fibular (Peroneal) Artery: The primary blood supply to the fibula, running close to the bone and providing periosteal branches.
- Nutrient Artery: Present, although the contribution is generally smaller than the nutrient artery of the tibia.
- Metaphyseal and Epiphyseal Arteries: Derived from the fibular artery and branches of the anterior and posterior tibial arteries.
In summary, the blood supply to the leg bones is a complex network involving nutrient arteries that enter the bone directly, periosteal arteries that supply the outer layer, and metaphyseal/epiphyseal arteries that nourish the ends of the bones. The femoral, popliteal, anterior tibial, posterior tibial, and fibular (peroneal) arteries and their branches are the major vessels involved.
