(31) Leg

Overview of Leg Bones

• The term "leg" in anatomy refers specifically to the region between the knee and the ankle.

• The leg contains two major bones:

  • Tibia: a large diameter bone located medially.

  • Fibula: a slender bone located laterally.

Tibia

• Anterior View of the Tibia

  • The proximal end has two regions called the condyles:

    • Lateral Condyle: articulates with the lateral condyle of the femur.

    • Medial Condyle: articulates with the medial condyle of the femur.

  • Tibial Tuberosity:

    • Located near the proximal end, on the anterior side.

    • Positioned just distal to the patella.

    • Functions as the site of attachment for a ligament connecting to the patella, anchoring it in place.

  • Distal End Features:

    • Medial Malleolus:

      • The feature that extends downward on the tibia.

      • Serves as the anchor point for the ankle joint, where the tarsal bone called the talus rests against it.

      • Can be palpated as the bony projection on the inside of the ankle.

Fibula

• Characteristics of the Fibula:

  • A long and slender bone that does not bear much body weight.

  • Weight Bearing:

    • The tibia carries most of the weight when standing.

  • Distal End Features:

    • Lateral Malleolus:

      • Located at the distal end of the fibula.

      • Helps support and anchor the ankle joint, similarly to the medial malleolus, by resting against the talus.

Overview of Leg Bones

When we talk about our legs in anatomy, we mean the part between our knees and our ankles. Our legs have two main bones:

1. Tibia: This is the bigger bone that is located towards the inside of our legs.

2. Fibula: This is the thinner bone that is located towards the outside of our legs.

Tibia

• Tibia's Top Part: The upper end of the tibia has two bumps called condyles:

  • Lateral Condyle: This bump fits with the side bump of the thigh bone (femur).

  • Medial Condyle: This bump fits with the inside bump of the femur.

• Tibial Tuberosity: Near the top of the tibia, on the front side, there's a spot called the tibial tuberosity:

  • It's just below the kneecap (patella) and helps a strong band called a ligament hold the kneecap in place.

• Bottom Part of Tibia: The lower part has an important feature called the Medial Malleolus:

  • This part sticks down and helps hold our ankle joint together. We can feel it as the bony point on the inside of our ankle.

Fibula

• Fibula's Features: The fibula is a long, thin bone that is not heavy:

  • It doesn’t carry much weight, so when we stand, the tibia does most of the work.

• Bottom Part of Fibula: The lower end of the fibula has a bump called the Lateral Malleolus:

  • This part helps support the ankle joint, just like the medial malleolus on the tibia.

So, our legs have two important bones that help us stand, walk, and move around!