Practical Class 4: Anterior and Medial Compartments of the Thigh Flashcards
From which muscle is the patella derived?
The tendon of quadriceps muscles.
Name the quadriceps muscles.
Vastus intermedius
Rectus femoris
Vastus lateralis
Vastus medialis
Which of the quadriceps muscles pulls at a much more oblique angle than the other three and why?
Vastus medialis - an attempt to prevent the patella being pulled too laterally
What other mechanism prevents the patella from being pulled too laterally?
Bony ridge on the lateral femoral condyle - if underdeveloped it may lead to recurrent dislocations of the patella.
What does avulsed mean?
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.
What are the menisci and where are they situated?
- 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
Describe the intrinsic ligaments of the knee.
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
Describe the collateral ligaments of the knee?
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
What are the boundaries of the femoral triangle?
- Superiorly by the inguinal ligament.
- Medially by the lateral border of the adductor longus muscle.
- Laterally by the medial border of the sartorius muscle.
What are the contents of the femoral triangle?
- 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.
What muscles are supplied by the femoral nerve?
Anterior division branches - sartorius - pectineus Posterior division branches - rectus femoris - vastus medialis - vastus lateralis - vastus intermedius
Describe the attachments of sartorius.
Proximal - ASIS and superior part of notch inferior to it
Distal - Superior part of medial surface of tibia
What is the innervation of sartorius?
Femoral nerve - L2-3
What are the actions of sartorius?
Flexes, abducts and laterally rotates thigh and hip joint; flexes leg at knee joint, (medially rotating leg when knee is flexed)
What are the boundaries of the adductor canal?
Anteriorly - sartorius.
Postermedially - adductor longus and adductor magnus.
Laterally - vastus medialis.
What are the proximal attachments of quadriceps femoris?
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
What are the distal attachments of quadriceps femoris?
Via quadriceps tendon and independent attachments to base of patella.
Indirectly via patella ligament to tibial tuberosity.
What is the innervation of the quadriceps muscles?
Femoral nerve L2-4
What are the main actions of the quadriceps muscles?
Extend the leg at the knee joint.
What are the muscles of the medial (adductor) compartment of the thigh?
- Adductor longus
- Adductor brevis
- Adductor magnus
- Gracilis
- Obturator externus
What is the chief function of the medial muscles of the thigh?
Adduction
What is the proximal attachment of adductor longus?
Body of pubis inferior to pubic crest.
What is the distal attachment of adductor longus?
Middle third of linea aspera of femur
What is the innervation of adductor longus?
Obdurator nerve, branch of anterior division L2-4
What is the action of adductor longus?
Adduction of the thigh
What is the proximal attachment of adductor brevis?
Body of inferior pubic ramus.
What is the distal attachment of adductor brevis?
Pectineal line and proximal part of linea aspera of femur.
What is the innervation to adductor brevis?
Obdurator nerve, branch of anterior division L2-4
What are the actions of adductor brevis?
Adducts thigh, to some extent flexes it.
What are the proximal attachments of adductor magnus?
Adductor part: Inferior ramus of pubis, ramus of ischium
Hamstrings part: Ischial tuberosity
What are the distal attachments of adductor magnus?
Adductor part: Gluteal tuberosity, linea aspera, medial spracondylar line
Hamstrings part: Adductor tubercle of femur
What is the innervation to adductor magnus?
Adductor part: obdurator nerve (L2-4) branches of posterior division
Hamstring part: tibial part of sciatic nerve L4
What are the actions of adductor magnus?
Adducts thigh
Adductor part: flexes thigh
Hamstring part: extends thigh
What is the proximal attachment of gracilis?
Body and inferior ramus of pubis.
What is the distal attachment of
Superior part of medial surface of tibia.
What is the innervation to gracilis?
Obturator nerve L2-3
What are the actions of gracilis?
Adducts thigh
Flexes leg
Helps rotate leg medially
What are the proximal attachments of obturator externus?
Margins of obturator foramen and obturator foramen.
What are the distal attachments of obturator externus?
Trochanteric fossa of femur
What is the innervation to obturator externus?
Obturator nerve L3-4
What are the main actions of obturator externus?
Laterally rotates thigh; steadies head of femur in acetabulum.
Where is the adductor hiatus?
About 8-13.5 cm. superior to the adductor tubercle.
