Lower extremity of femur

Condyles

Anteriorly, the condyles are slightly prominent and are separated by a smooth shallow articular depression called the patella surface. Posteriorly, they project considerably and a deep notch, the intercondylar fossa of femur, is present between them.

The lateral condyle is the more prominent and is the broader both in its antero-posterior and transverse diameters, the medial condyle is the longer and, when the femur is held with its body perpendicular, projects to a lower level.

However, when the femur is in its natural oblique position, the lower surfaces of the two condyles lie practically in the same horizontal plane.

The condyles are not quite parallel with one another; the long axis of the lateral is almost directly antero-posterior, but that of the medial runs backward and medialward.

Their opposed surfaces are small, rough, and concave, and form the walls of the intercondylar fossa.

This fossa is limited above by a ridge, the intercondyloid line, and below by the central part of the posterior margin of the patellar surface.

The posterior cruciate ligament of the knee joint is attached to the lower and front part of the medial wall of the fossa and the anterior cruciate ligament to an impression on the upper and back part of its lateral wall.

Epicondyles

Each condyle is surmounted by an elevation, the epicondyle.

The medial epicondyle is a large convex eminence to which the medial collateral ligament of the knee-joint is attached.

At its upper part is the adductor tubercle, and behind it is a rough impression which gives origin to the medial head of the gastrocnemius.

The lateral epicondyle, smaller and less prominent than the medial, gives attachment to the fibular collateral ligament of the knee-joint.

Directly below it is a small depression from which a smooth well-marked groove curves obliquely upward and backward to the posterior extremity of the condyle.

This groove is separated from the articular surface of the condyle by a prominent lip across which a second, shallower groove runs vertically downward from the depression.

In the fresh state these grooves are covered with cartilage.

The popliteus arises from the depression; its tendon lies in the oblique groove when the knee is flexed and in the vertical groove when the knee is extended.

Above and behind the lateral epicondyle is an area for the origin of the lateral head of the gastrocnemius, above and to the medial side of which the plantaris arises.