Femur

Gluteal Ridge

Also called the Gluteal Line or Crest is a long, wide, roughened, posterolaterally placed feature that extends from the base of the greater trochanter to the lateral lip of the linea aspera. It can be a depression or it can assume the form of a true tuberosity. If the latter is present, it is often referred to as the third trochanter. It is the insertion for part of the gluteus maximus muscle, an extensor, abductor, and lateral rotator of the thigh at the hip that originates on the posterior half of the os coxae, the sacrum, and the coccyx.

Intercondylar Fossa

Also called the Intercondylar Notch, this is the nonarticular, excavated surface between the distal and posterior articular surfaces of the condyles. Within the fossa are two facets that are the femoral attachment sites of the anterior and posterior cruciate ligaments, a pair of crossed ligaments linking the femur and tibia. These ligaments strengthen the knee joint.

Lateral Supracondylar Ridge

Also called the Lateral Supracondylar Line, this is the inferior, or distal, lateral extension of the linea aspera. It is more pronounced than the medial supracondylar line.

Medial Supracondylar Ridge

Also called the Medial Supracondylar Line, this is the inferior, medial extension of the linea aspera, marking the distal, medial corner of the shaft. It is fainter than the lateral supracondylar line.

Lesser Trochanter

The blunt, prominent tubercle on the posterior femoral surface just inferior to the point where the neck joins the shaft. This is the point of insertion of the iliopsoas tendon, the common tendon of the iliacus muscle, originating in the iliac fossa, and the psoas major muscle, originating from the lumbar vertebrae and their disks. These muscles are major flexors of the thigh at the hip.

Intertrochanteric Crest

The elevated line on the posterior surface of the proximal femur between the greater and lesser trochanters. It passes from superolateral to inferomedial. Just above its midpoint is a small tubercle, the quadrate tubercle, which is the site of insertion of the quadratus femoris muscle, a lateral rotator of the femur.

Femoral Shaft

The long section between the expanded proximal and distal ends of the bone.

Linea Aspera

The long, wide, roughened, and elevated ridge that runs along the posterior shaft surface. It collects the spiral line, pectineal line, and gluteal tuberosity proximally and divides into the medial and lateral supracondyloid ridges distally. The linea aspera is a primary origin site for the vastus muscles and the primary insertion site of the adductors, longus, brevis, and magnus, of the hip.

Femoral Head

The rounded proximal part of the bone that fits into the acetabulum. It constitutes more of a sphere than the hemispherical humeral head.

Intertrochanteric Line

The variable, fairly vertical, roughened line that passes between the lesser and greater trochanters on the anterior surface of the base of the neck of the femur. Superiorly, this line anchors the iliofemoral ligament, which is the largest ligament in the human frame. It acts to strengthen the joint capsule of the hip.

Femoral Neck

This connects the femoral head with the shaft and the greater trochanter.

Patellar Surface

This is a notched articular area on the anterior surface of the distal femur, over which the patella glides during fl exion and extension of the knee. The lateral surface of this notch is elevated, projecting more anteriorly than the medial boundary of the notch. This helps prevent lateral dislocation of the patella during full extension of the knee.

Nutrient Foramen

This is located about midshaft level on the posterior surface of the bone, adjacent to or on the linea aspera. This foramen exits the bone distally.

Lateral Epicondyle

This is the convexity on the lateral side of the lateral condyle. It is an attachment point for the lateral collateral ligament of the knee. Its upper surface bears a facet that is an attachment point for one head of the gastrocnemius muscle, a flexor of the knee and plantarflexor of the foot at the ankle.

Medial Epicondyle

This is the convexity on the medial side of the medial condyle. It is a point of attachment for the medial collateral ligament of the knee.

Medial Condyle

This is the large, articular knob on the medial side of the distal femur. Its medial surface bulges away from the axis of the shaft. The medial condyle extends more distally than the lateral condyle.

Greater Trochanter

This is the large, blunt, nonarticular prominence on the lateral, proximal part of the femur. It is the insertion site for the gluteus minimus, anterior aspect of the trochanter, and gluteus medius muscles, posterior aspect, both major abductors of the thigh and stabilizers of the hip. Their origins are on the broad, flaring iliac blade of the os coxae. These muscles are crucial in stabilizing the trunk when one leg is lifted from the ground during bipedal locomotion.

Lateral Condyle

This is the large, protruding, articular knob on the lateral side of the distal femur.

Fovea Capitis

This is the small, nonarticular depression near the center of the head of the femur. It receives the ligamentum teres from the acetabular notch of the os coxae.

Adductor Tubercle

This is the variable, raised tubercle on the medial supracondylar line just superior to the medial epicondyle. It is an attachment point for the adductor magnus, a muscle originating on the lower edge of the ischiopubic ramus and ischial tuberosity. This muscle adducts the thigh at the hip.

Popliteal Surface

This is the wide, flat, triangular area of the posterior, distal femur. It is bounded by the condyles inferiorly and by the supracondylar lines medially and laterally.

Siding the Femur

-For intact femora or proximal ends, the head is proximal and faces medially. The lesser trochanter and linea aspera are posterior. -For isolated femoral heads, the fovea is medial and displaced posteriorly and inferiorly. The posteroinferior head-neck junction is more deeply excavated than the anterosuperior junction. -For proximal femoral shafts, the nutrient foramen opens distally, and the linea aspera is posterior and thins inferiorly. The gluteal tuberosity is superior and faces posterolaterally. -For femoral midshafts, the nutrient foramen opens distally, the bone widens distally, and the lateral posterior surface is usually more concave than the medial posterior surface. -For distal femoral shafts, the shaft widens distally and the lateral supracondylar ridge is more prominent than the medial. The medial condyle extends more distally than the lateral. -For femoral distal ends, the intercondylar notch is posterior and distal, and the lateral border of the patellar notch is more elevated. The lateral condyle bears the popliteal groove, and the medial condyle bulges away from the line of the shaft. Relative to the shaft axis, the lateral condyle extends more posteriorly than the medial. The medial condyle extends more distally than the lateral because in anatomical position the femur angles beneath the body.