Practical Class 4: Anterior and Medial Compartments of the Thigh

Question 1

From which muscle is the patella derived?

Answer 1

The tendon of quadriceps muscles.

Question 2

Name the quadriceps muscles.

Answer 2

Vastus intermedius
Rectus femoris
Vastus lateralis
Vastus medialis

Question 3

Which of the quadriceps muscles pulls at a much more oblique angle than the other three and why?

Answer 3

Vastus medialis - an attempt to prevent the patella being pulled too laterally

Question 4

What other mechanism prevents the patella from being pulled too laterally?

Answer 4

Bony ridge on the lateral femoral condyle - if underdeveloped it may lead to recurrent dislocations of the patella.

Question 5

What does avulsed mean?

Answer 5

Avulsion injuries, where a portion of cortical bone is ripped from the rest of the bone by the attached tendon, are common among those who participate in sports, and there are numerous sites at which these occur.

Question 6

What are the menisci and where are they situated?

Answer 6

• 2 c-shaped wedges of fibrocartilage
• External edges attach to the fibrous capsule of the joint
• Medial meniscus is firmly attached to the tibial collateral ligament

Question 7

Describe the intrinsic ligaments of the knee.

Answer 7

Anterior cruciate ligament - Prevents anterior displacement of the tibia on the femur, prevents hyperextension

Posterior cruciate ligament - Prevents posterior displacement of the tibia on the femur, prevents hyperflexion, main stabiliser of the flexed knee when weight bearing e.g. walking down hill

Question 8

Describe the collateral ligaments of the knee?

Answer 8

Tibial (medial) collateral ligament

• Flat band attached to medial meniscus
• Prevents abduction of the leg at the knee

Fibular (lateral) collateral ligament

• Cord like band NOT attached to lateral meniscus
• Prevents adduction of the leg at the knee

Question 9

What are the boundaries of the femoral triangle?

Answer 9

• Superiorly by the inguinal ligament.
• Medially by the lateral border of the adductor longus muscle.
• Laterally by the medial border of the sartorius muscle.

Question 10

What are the contents of the femoral triangle?

Answer 10

• Femoral nerve and its (terminal) branches.
• Femoral sheath and its contents:
• Femoral artery and several of its branches.
• Femoral vein and its proximal tributaries (e.g., the great saphenous and deep femoral veins).
• Deep inguinal lymph nodes and associated lymphatic vessels.

Question 11

What muscles are supplied by the femoral nerve?

Answer 11

Anterior division branches
   - sartorius 
   - pectineus 
Posterior division branches
   - rectus femoris 
   - vastus medialis 
   - vastus lateralis 
   -  vastus intermedius

Question 12

Describe the attachments of sartorius.

Answer 12

Proximal - ASIS and superior part of notch inferior to it

Distal - Superior part of medial surface of tibia

Question 13

What is the innervation of sartorius?

Answer 13

Femoral nerve - L2-3

Question 14

What are the actions of sartorius?

Answer 14

Flexes, abducts and laterally rotates thigh and hip joint; flexes leg at knee joint, (medially rotating leg when knee is flexed)

Question 15

What are the boundaries of the adductor canal?

Answer 15

Anteriorly - sartorius.
Postermedially - adductor longus and adductor magnus.
Laterally - vastus medialis.

Question 16

What are the proximal attachments of quadriceps femoris?

Answer 16

Rectus femoris - ASIS and ilium superior to acetabulum

Vastus lateralis - Greater trochanter and lateral lip of linea aspera of femur

Vastus medialis - Intertrochanteric line and medial lip of linea aspera

Vastus intermedius - Anterior and lateral surfaces of shaft of femur

Question 17

What are the distal attachments of quadriceps femoris?

Answer 17

Via quadriceps tendon and independent attachments to base of patella.

Indirectly via patella ligament to tibial tuberosity.

Question 18

What is the innervation of the quadriceps muscles?

Answer 18

Femoral nerve L2-4

Question 19

What are the main actions of the quadriceps muscles?

Answer 19

Extend the leg at the knee joint.

Question 20

What are the muscles of the medial (adductor) compartment of the thigh?

Answer 20

• Adductor longus
• Adductor brevis
• Adductor magnus
• Gracilis
• Obturator externus

Question 21

What is the chief function of the medial muscles of the thigh?

Answer 21

Adduction

Question 22

What is the proximal attachment of adductor longus?

Answer 22

Body of pubis inferior to pubic crest.

Question 23

What is the distal attachment of adductor longus?

Answer 23

Middle third of linea aspera of femur

Question 24

What is the innervation of adductor longus?

Answer 24

Obdurator nerve, branch of anterior division L2-4

Question 25

What is the action of adductor longus?

Answer 25

Adduction of the thigh

Question 26

What is the proximal attachment of adductor brevis?

Answer 26

Body of inferior pubic ramus.

Question 27

What is the distal attachment of adductor brevis?

Answer 27

Pectineal line and proximal part of linea aspera of femur.

Question 28

What is the innervation to adductor brevis?

Answer 28

Obdurator nerve, branch of anterior division L2-4

Question 29

What are the actions of adductor brevis?

Answer 29

Adducts thigh, to some extent flexes it.

Question 30

What are the proximal attachments of adductor magnus?

Answer 30

Adductor part: Inferior ramus of pubis, ramus of ischium Hamstrings part: Ischial tuberosity

Question 31

What are the distal attachments of adductor magnus?

Answer 31

Adductor part: Gluteal tuberosity, linea aspera, medial spracondylar line Hamstrings part: Adductor tubercle of femur

Question 32

What is the innervation to adductor magnus?

Answer 32

Adductor part: obdurator nerve (L2-4) branches of posterior division Hamstring part: tibial part of sciatic nerve L4

Question 33

What are the actions of adductor magnus?

Answer 33

Adducts thigh Adductor part: flexes thigh Hamstring part: extends thigh

Question 34

What is the proximal attachment of gracilis?

Answer 34

Body and inferior ramus of pubis.

Question 35

What is the distal attachment of

Answer 35

Superior part of medial surface of tibia.

Question 36

What is the innervation to gracilis?

Answer 36

Obturator nerve L2-3

Question 37

What are the actions of gracilis?

Answer 37

Adducts thigh Flexes leg Helps rotate leg medially

Question 38

What are the proximal attachments of obturator externus?

Answer 38

Margins of obturator foramen and obturator foramen.

Question 39

What are the distal attachments of obturator externus?

Answer 39

Trochanteric fossa of femur

Question 40

What is the innervation to obturator externus?

Answer 40

Obturator nerve L3-4

Question 41

What are the main actions of obturator externus?

Answer 41

Laterally rotates thigh; steadies head of femur in acetabulum.

Question 42

Where is the adductor hiatus?

Answer 42

About 8-13.5 cm. superior to the adductor tubercle.