Femur: The femur has a long cylinderical body with two expanded extremities. The proximal extremity composed of a smooth head separated by a neck from the medial side of the bone. The head contains a small shallow fossa, the fovea capitis femoris, to which the ligament of the head of the femur attaches. The neck of the femur is short and distinct and provides attachment for the joint capsule. A large eminence, the greater trochanter is located directly lateral to the head and provides attachement for the middle and deep gluteal muscles. Medial to the greater trochanter is a deep fossa, the trochanteric fossa for the insertion of gamelli and external and internal obturator muscles. The lesser trochanter is a projection at the proximal end of the medial side of the body of the femur, which serves for the insertion of the iliopsoas. A ridge of bone extends between the greater and lesser trochanter forming the intertrochanteric crest. The third trochanter is poorly developed in the dog.
The body of the femur is slightly convex and smooth cranially. Its caudal surface is rough with medial and lateral lips. The distal extremity of the femur includes the trochlea that articulates with the patella. The trochlea is continuous with the condyles, which articulate with the tibia directly and through fibrocartilaginous menisci. A deep wide space, the intercondylar fossa separates the medial and lateral condyles.