1.2.6.1. Muscles of the Anterior Compartment of the Thigh Flashcards
What are the 3 Muscle Compartments of the Thigh?
- Anterior Compartment of the Thigh
- Medial Compartment of the Thigh
- Posterior Compartment of the Thigh
What are the Muscles of the Anterior Compartment of the Thigh innervated by?
The Femoral Nerve
What is the Segmental (or Root) Values for the Femoral Nerve?
- L2
- L3
- L4
In general, what is the function of the Muscles of the Anterior Compartment of the Thigh?
Extension of the Leg at the Knee Joint
What are the 3 major Muscles in the Anterior Compartment of the Thigh?
- Pectineus Muscle
- Sartorius Muscle
- Quadriceps Femoris Muscles
Note - The End of the Iliopsoas Muscle also passes into the Anterior Compartment of the Thigh
What does the Pectineus Muscle form?
The base of the Femoral Triangle
How is the Pectineus Muscle described?
A flat Muscle
Where does the Pectineus Muscle originate from?
Pectineal Line, on the Anterior Surface of the Pelvis
Where does the Pectineus Muscle attach distally?
Pectineal Line, on the Posterior Surface of the Femur
Note - it attaches just Inferiorly to the Lesser Trochanter of the Femur
What is the function of the Pectineus Muscle?
- Adduction of the Thigh at the Hip Joint
2. Flexion of the Hip Joint
What is the innervation of the Pectineus Muscle?
It has a dual innervation:
- Femoral Nerve (L2-L4)
- It may also receive a branch from the Obturator Nerve
What is the significance of the dual innervation of the Pectineus Muscle?
It can be considered a transitional muscle between the Anterior and Medial Compartments of the Thigh
What is significant about the Sartorius Muscle?
It is the longest Muscle in the Body
How is the Sartorius Muscle described?
It is Long, and Thin
In which direction does the Sartorius Muscle run?
Inferomedially
Where is the Sartorius Muscle positioned, in relation to the other Muscles of the Anterior Compartment of the Thigh?
It is more Superficial
Where does the Sartorius Muscle originate from?
Anterior Superior Iliac Spine
Where does the Sartorius Muscle attach distally?
Superior, Medial surface of the Tibia
What is the function of the Sartorius Muscle?
- Flexion of the Hip Joint
- Abduction of the Hip Joint
- Lateral Rotation of the Hip Joint
- Flexion of the Knee Joint
What is the innervation of the Sartorius Muscle?
The Femoral Nerve (L2-L4)
How many Muscles is the Quadriceps Femoris Muscles formed of?
4
What are the 4 Quadriceps Femoris Muscles?
3 x Vastus Muscles:
- Vastus Lateralis Muscle
- Vastus Intermedius Muscle
- Vastus Medialis Muscle
1 x Rectus Femoris:
1. Rectus Femoris Muscle
Where does the Vastus Lateralis Muscle originate from?
- Greater Trochanter of the Femur
2. Lateral Lip of the Linea Aspera of the Femur
What is the function of the Vastus Lateralis Muscle?
- Extension of the Knee Joint
2. Stabilization of the Patella
What is the innervation of the Vastus Lateralis Muscle?
The Femoral Nerve (L2-L4)
Where does the Vastus Intermedius Muscle originate from?
- Anterior Surface of the Femoral Shaft
2. Lateral Surface of the Femoral Shaft
What is the function of the Vastus Intermedius Muscle?
- Extension of the Knee Joint
2. Stabilization of the Patella
What is the innervation of the Vastus Intermedius Muscle?
The Femoral Nerve (L2-L4)
Where does the Vastus Medialis Muscle originate from?
- Intertrochanteric Line of the Femur
2. Medial Lip of the Linea Aspera of the Femur
What is the function of the Vastus Medialis Muscle?
- Extension of the Knee Joint
- Stabilization of the Patella
Note - Particularly due to its Horizontal Fibers at the Distal End
What is the innervation of the Vastus Medialis Muscle?
The Femoral Nerve (L2-L4)
Where does the Rectus Femoris Muscle originate from?
The Ilium, just Superiorly to the Acetabulum
Where does the Rectus Femoris Muscle travel?
Straight down the Thigh
Note - Latin for “Straight” is “Rectus”
What is the significance of the Rectus Femoris Muscle, in relation to the other Quadriceps Femoris Muscles?
It is the only Quadriceps Femoris Muscle to cross the Hip and Knee Joint
What is the function of the Rectus Femoris Muscle?
- Flexion of the Thigh at the Hip Joint
2. Flexion of the Leg at the Knee Joint
What is the innervation of the Rectus Femoris Muscle?
The Femoral Nerve (L2-L4)
What happens to the Quadriceps Femoris Muscles, immediately proximal to the Knee Joint?
They Unite, forming the Quadriceps Femoris Tendon
Where does the Quadriceps Femoris Tendon attach distally?
The Patella
How does the Patella attach to the Tibia?
- The Patellar Ligament
2. The Patellar Tendon
What is the main Extensor of the Knee?
The Quadriceps Femoris Muscles
How many Muscles form the Iliopsoas Muscle?
2
What are the Muscles which form the Iliopsoas Muscle?
- The Psoas Major Muscle
2. The Iliacus Muscle
Why is the Iliopsoas Muscle referred to as 1 Muscle, even though it originates from 2 different areas?
They come together to form 1 Tendon
Where does the Psoas Major Muscle originate from?
The Vertebral Bodies, and associated Intervertebral Disks of:
- T12
- L1
- L2
- L3
Where does the Iliacus Muscle originate from?
The Iliac Fossa of the Pelvis
Where does the Iliopsoas Muscle (Tendon) attach distally?
The Lesser Trochanter of the Femur
What is the function of the Iliopsoas Muscle?
- Flexion of the Hip Joint
2. (It assists in) Lateral Rotation of the Hip Joint
Does the Iliopsoas Muscle Extend the Leg at the Knee Joint?
No, unlike many of the Muscles of the Anterior Compartment of the Thigh, it does not
What is the innervation of the Psoas Major Muscle?
The Anterior Rami of L1 - L3
What is the innervation of the Iliacus Muscle?
The Femoral Nerve (L2-L4)
