Lower limb 2 - Posterior thigh and popliteal fossa Flashcards
What does the femur consist of?
robust shaft
2 complex expanded articular ends
What does the femur articulate with?
acetabulum and distally with the tibia
What is the proximal head of the femur like and what does it join to?
has a spherical head
joined to shaft of the femur by the neck
In what direction does the daft of the femur pass as it approaches the femur of the opposite thigh?
medially
What is the femoral shaft like generally and what is the exception?
generally - cylindrical and smooth
except for - linea aspera
What is the linea aspera and what does it form the attachment sites for?
a pair of ridges that run longitudinally along the dorsal surface
attachment site - for several muscles of the thigh
NOTE
make sure you know all the bony prominences on femur
What is the fascia lata?
a layer of deep fascia which surrounds the muscles of the thigh
What does the fascia lata form and what do they attach to and what 3 compartments do they divide the muscles of the thigh into?
- forms - 3 inter muscular septa
- 3 inter muscular septa attach to linea aspera
- 3 compartments:
- anterior extensor
- posterior flexor
- medial adductor
What muscles make up the hamstring?
- semimembranosus
- semitendinosus
- biceps femoris - long head
What do the 3 muscles of the hamstring share in common?
- the same proximal attachment
- and same innervation
What is the proximal attachment and innervation of the 3 muscles of the hamstring?
proximal attachment - ischial tuberosity
innervation - sciatic nerve
What are the distal insertions of the hamstrings?
biceps femoris - head of fibula
semitendinosus - media surface of the proximal tibia
semimembranosus - groove and adjacent bone on medial posterior surface of medial head of medial tibial condyle
Why is the short head of biceps femoris not considered as one of the hamstring muscles?
it doesn’t share the common proximal attachment and innervation
What are the attachments and innervation of the short head of biceps femoris?
attachment - lateral lip of linea aspera
insertion - head of fibula
innervation - sciatic nerve
What is the function of the biceps femoris?
laterally rotates thigh at hip joint
flexes leg at knee joint
What is the function of semitendinosus?
medially rotates thigh at hip joint
flexes leg at knee joint
What is the function of semimembranosus?
extends thigh at hip joint and medially rotates thigh
flexes leg at knee joint
Which compartment is the adductor magnus in?
medial compartment
What can the adductor magnus be divided into?
- hamstrings
2. adductor part
What is the nerve and proximal attachment of the adductor part of the adductor magnus?
- obturator nerve
2. ischiopubic ramus
What is the nerve and proximal attachment of the hamstring part of the adductor magnus?
sciatic nerve
ischial tuberosity
Why is the hamstring part of the adductor magnus considered to be part of the hamstrings?
same origin/ proximal attachment of ischial tuberosity as the other hamstrings
What does the sciatic nerve divide into and where do they both enter?
common fibular/peroneal - laterally
tibial nerves - medially
popliteal fossa
What is the popliteal fossa?
a diamond shaped depression located on the posterior aspect of the knee.
What are the borders of the popliteal fossa?
superomedially - semitendinosus and semimembranosus
superolaterally - biceps femoris
inferomedially - medial head gastrocnemius
inferolaterally - lateral head of gastrocnemius
What forms the roof and floor of the popliteal fossa?
roof - popliteal fascia and skin
floor - posterior surface of knee joint capsule and femur
What do plantaris and gastrocnemius do?
flexor of knee
plantar flexor of ankle joint
