Hello, I'm Professor Nalini Pather from
the University of New South Wales in Sydney, Australia.
Today we're going to talk about the leg and the ankle.
The structure of this lecture is really going to cover the bones of
the leg and foot, and then a little general remarks about the ankle joint,
then we will discuss the muscles of the leg and the nerves that supply the leg.
The leg is part of the lower limb that extends from the knee to the ankle joint.
Its skeletal framework consists of two bones, both long bones.
They are the tibia and the laterally placed fibula.
The tibia lies medially in the leg and is the larger of the two leg bones.
It is more robust and plays a significant role in bearing the weight of the body.
It is a long bone and so has two ends and a shaft.
The shaft is triangular in cross-section.
It presents proximally two shallow condyles called the medial and lateral condyles.
The lateral condyle articulates with the head of the fibula.
Proximally, the tibia has a distinct tibial tuberosity.
Superiorly, these condyles present an intercondylar ridge.
This ridge lies on a flat plateau.
Attaching to the condyle superiorly on the plateau are the medial and lateral menisci.
The intercondylar ridge itself gets its attachment to
the anterior and posterior cruciate ligaments respectively.
The shaft of the tibia has a distinct anterior border.
This border is prominent and subcutaneous.
Laterally, there is a sharp interosseous border as well
for the attachment of the interosseous membrane that connects this bone,
the tibia, to the adjacent fibula.
Posteriorly on the superior surface of the shaft is
an oblique line called the soleal line for the attachment of the soleus muscle.
The distal end of the tibia has some prominent features.
Medially there's a prominent medial malleolus.
These present articular surfaces for the ankle joint.
The lateral surface of the tibia inferiorly also
presents a facet for the articulation with the fibula.