Anteriorly, the condyles are slightly prominent and are separated by a smooth shallow articular depression called the patella surface.

When, however, 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.

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.

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.

The lateral groove is the better marked; it runs lateralward and forward from the front part of the intercondyloid fossa, and expands to form a triangular depression.