FEMUR ANATOMY

GENERAL STRUCTURE

The femur is the longest and strongest bone in your body, characterized as a long bone with a central shaft and two ends. It plays a vital role in bearing your weight and enabling movement, with its proximal end connecting to your hip joint, its body supporting muscular attachments, and its distal end forming part of your knee joint.

Body (Shaft)

What is the body of the femur?

• The femur shaft is a long, cylindrical, and slightly curved structure
• Connects the upper and lower ends of the femur
• Supports weight-bearing and facilitates your movement
• Notable features include the linea aspera
  • A ridge located on the back of the shaft
  • Serves as an attachment site for muscles

Proximal Epiphysis

What is the proximal epiphysis of the femur?

• It is the upper part of the femur
• Forms part of your hip joint

Distal Epiphysis

What is the distal epiphysis of the femur?

• It is the lower part of the femur
• Forms part of your knee joint

PROXIMAL EPIPHYSIS OF THE FEMUR

The Proximal Epiphysis is the upper part of your femur. It plays a crucial role in connecting to your hip joint, supports your mobility and stability, and describes the following structures:

Head of the Femur

What is the head of the femur?

• Structure
  • Round, ball-like, spherical shape
  • Forms more than half of a sphere
• Orientation
  • Points slightly upwards and towards your body's center
• Function
  • Fits into the acetabulum (hip socket) for smooth hip joint movement
• Feature: Fovea for the Ligament of the Head
  • Small depression on the surface of the head
  • Location: Slightly below and behind the center
  • Function: Attachment site for a ligament that stabilizes your hip joint

Neck of the Femur

What is the neck of the femur?

• Structure
  • Narrow, flattened region
• Function
  • Connects the head of the femur to its body
  • Forms an angle with the femur's body for proper hip movement and stability

Greater Trochanter

What is the greater trochanter?

• Structure
  • Large, irregular bony prominence
  • Projects upwards and outwards from the femur
• Function
  • Major attachment point for several muscles involved in your hip and thigh movement
• Feature: Trochanteric Fossa
  • Location: Inner surface of the greater trochanter
  • Function: Attachment point for a tendon aiding your hip movement

Lesser Trochanter

What is the lesser trochanter?

• Structure
  • Smaller, cone-shaped projection
  • Located at the junction of the femur's body and neck, towards the back
• Function
  • Attachment point for muscles like the psoas major, aiding your hip flexion

Intertrochanteric Line

What is the intertrochanteric line?

• Location
  • Front surface of the femur
  • Runs downward and inward from the greater trochanter to the lesser trochanter
• Function
  • Marks the boundary between the neck and body of the femur
  • Provides attachment points for muscles and ligaments

Intertrochanteric Crest

What is the intertrochanteric crest?

• Location
  • Back surface of the femur
  • Runs diagonally between the greater and lesser trochanters
• Function
  • Provides an area for muscle attachment
  • Serves as a key anatomical landmark

Quadrate Tubercle

What is the quadrate tubercle?

• Location
  • Along the intertrochanteric crest, about halfway between the greater and lesser trochanters
• Function
  • Attachment point for the Quadratus femoris muscle, aiding in your hip stabilization

BODY OF THE FEMUR

The shaft of your femur is almost cylindrical for most of its length, broadening above its midpoint and flattening near the distal end. It describes the following structures:

Linea Aspera

What is the linea aspera?

• Location
  • Longitudinal ridge running down the posterior surface
• Function
  • Attachment point for muscles like your adductors and quadriceps
• Features
  • Medial Lip - Defines the inner margin; attachment site for your vastus medialis muscle
  • Lateral Lip - Forms the outer edge; attachment site for your vastus lateralis muscle

Pectineal Line

What is the pectineal line?

• Location
  • Extends upwards from the linea aspera toward the lesser trochanter
• Function
  • Attachment site for a muscle
  • Transitions into the anterior part of the femur, blending with the intertrochanteric line

Gluteal Tuberosity

What is the gluteal tuberosity?

• Location
  • Upper posterior part of the femur, rising toward the base of the greater trochanter
• Function
  • Attachment point for the gluteus maximus muscle
  • Supports your hip extension and movement

Popliteal Surface

What is the popliteal surface?

• Location
  • Triangular area at the distal posterior end, bordered by diverging edges of the linea aspera
• Function
  • Related to muscle and ligament attachments near your knee joint

Medial Supracondylar Line

What is the medial supracondylar line?

• Location
  • Descends from the medial lip of the linea aspera to the medial condyle
• Function
  • Attachment site for muscles
  • Provides structural support

Lateral Supracondylar Line

What is the lateral supracondylar line?

• Location
  • Extends from the lateral lip of the linea aspera to the lateral epicondyle
• Function
  • Provides muscle attachment points
  • Defines the contour of your femur's lower posterior part

DISTAL EPIPHYSIS OF THE FEMUR

The lower part of your femur is located distally and serves as the connection to your knee joint. It features structures that articulate with your tibia and patella, and describes the following structures:

Medial Condyle

What is the medial condyle of the femur?

• Structure
  • Prominent, rounded projection on the lower, inner side of the femur
  • Extends further back than the lateral condyle
• Function
  • Articulates with your tibia to form part of your knee joint
• Features
  • Medial Epicondyle - Located above the medial condyle; attachment point for a ligament
  • Adductor Tubercle - Small, raised area on the medial condyle; attachment point for a muscle involved in your thigh adduction

Lateral Condyle

What is the lateral condyle of the femur?

• Structure
  • Broader and more anterior than the medial condyle
• Function
  • Articulates with your tibia to form part of your knee joint
• Features
  • Lateral Epicondyle - Located above the lateral condyle; attachment point for a ligament connecting the femur to the fibula
  • Groove for Popliteus Muscle - Oblique, deep groove on the back of the lateral condyle; passage for your popliteus muscle, separated from the articular surface by a rounded ridge

Patellar Surface

What is the patellar surface of the femur?

• Location
  • Front of the femur, between the medial and lateral condyles
• Function
  • Smooth, shallow depression that articulates with your patella
  • Allows smooth movement during your knee flexion and extension

Intercondylar Fossa

What is the intercondylar fossa?

• Location
  • Deep notch on the posterior side of the femur, between the condyles
• Function
  • Houses attachment points for your cruciate ligaments, essential for your knee stability

Intercondylar Line

What is the intercondylar line?

• Location
  • Ridge running across the back of the femur, above the intercondylar fossa
• Function
  • Connects to the posterior margin of the patellar surface
  • Serves as a boundary for the intercondylar fossa