Dissection 4 Flashcards
what are the borders of the popliteal fossa?
superomedial = sacrotuberous and sacromembranous muscles
superolateral = biceps femoris
inferomedial and lateral = gastrocnaemius
floor = capsule of the knee joint, distal femur and proximal tibia/popliteus muscle
roof = popliteal fascia
what pierces the popliteal fascia?
short saphenous vein
sural nerve
what are the 4 main nerves in the popliteal fossa?
tibial
common fibular
sural
posterior femoral cutaneous
where does the tibial nerve originate?
where the sciatic nerve bifurcates into the tibial and common fibular nerve at the superior angle of the popliteal fossa
tibial = larger, medial branch
describe the path of the tibial nerve
originates at the superior angle of the popliteal fossa
passes through the fossa inferiorly
exits deep to the plantaris muscle
enters posterior compartment of the leg
what does the tibial nerve supply?
soleus muscle
gastrocnaemius muscle
plantaris muscle
popliteal muscle
describe the path of the common fibular nerve?
smaller lateral branch of the sciatic nerve
traverses the fossa close to the medial border of the biceps femoris
exits the fossa superficial to the lateral head of the gastrocnaemius
crosses posterior aspect of the head of the fibula
winds around the neck of the fibula before dividing into its terminal branches
describe the path of the popliteal artery
enters popliteal fossa by passing under the semimembranous muscle
travels through the fossa inferolaterally
enters the posterior compartment of the leg
what does the popliteal artery do?
branches off to form 5 genicular arteries
- superior medial
- superior lateral
- middle
- inferior medial
- inferior lateral
all supply ligaments and capsule of the knee
gives off muscular branches which supply soleus, gastrocnaemius, plantaris and hamstrings
what forms the genicular anastomoses and what is its function?
the 5 genicular branches of the popliteal artery
surrounds the knee joint
maintains blood supply to the knee while flexed by bypassing the popliteal artery
what is the popliteal vein and where is it?
continuation of the posterior tibial vein
lies superficial to the popliteal artery within the same fibrous sheath
describe the path of the popliteal vein
continuation of the posterior tibial vein
exits the fossa superiorly and becomes the femoral vein as it passes through the adductor hiatus
what is the pathway of the short saphenous vein?
travels superiorly in the posterior aspect of the leg from the lateral part of the dorsal venous arch
travels within the popliteal fascia before penetrating it and anastomosing with the popliteal vein
what are the functions of the posterior muscles of the leg?
plantarflexion
flex the toes
invert the foot
2 can flex the knee
what nerve supplies the posterior compartment of the leg?
tibial branch of sciatic
what are the muscles of the superior posterior compartment?
gastrocnaemius
plantaris (small, thin)
soleus
where does the gastrocnaemius originate and insert?
medial and lateral heads originate on the medial and lateral heads of the femur
insert at the calcaneous (via achilles)
what are the functions of the gastrocnaemius?
plantarflexion and flexion of the knee
where does the plantaris originate and insert?
lower part of supracondylar ridge
inserts at calcaneous via achilles
what does the planatris do?
plantarflexion
flexion on knee
where does the soleus originate and insert?
proximal ends of tibia and fibula
inserts at the calcaneous via achilles
what does the soleus do?
plantarflexion
what are the 3 deep muscles in posterior compartment?
popliteus
where does the popliteus originate and insert?
originates on posterior surface of proximal tibia
inserts on lateral femoral condyle
penerates joint capsule of knee
what does the popliteus do?
unlocks the knee by laterally rotating the femur
what are the 4 deep muscles of the posterior compartment of the leg?
popliteus flexor hallicus longus (lateral) flexor digitorum longus (medial) tibialis posterior (intermediate)
where does the flexor hallicus longus originate and insert?
posterior surface of lower fibula and adjacent interosseous membrane and inserts at base on big toe
what does the flexor halicus longus do?
flexes the big toe
where does the flexor digitorum longus originate and insert?
originates posterior surface of medial tibia
inserts at bases of distal 4 lateral phalanges
what does the flexor digitorum longus do?
flexes the digits
where does the tibialis posterior originate and insert?
originates between the tibia and fibula at interosseous membrane
inserts on tuberosity of navicular and medial cuneiform
what does the tibialis posterior do?
plantarflexion
inverts the foot
supports medial arch of the foot
what/where is the sural nerve?
formed by fusion of branches of tibial and common fibular nerves
sits at posterior leg/ankle above the achilles
what is the flexor retinaculum?
thickening of the crural fascia which forms the roof of the tarsal tunnel
extends from medial malleolus to calcaneous
what is crural fascia?
deep fascia of the leg
where is the posterior tibial artery?
where the popliteal artery bifurcates into the posterior tibial and fibular arteries on the posterior surface of the tibia
what are vena comitants?
veins which lie in close proximity to an artery and use its pulsation to propel blood back up through them
what is the tarsal tunnel?
space at medial malleolus created by the flexor retinaculum which allows structures to pass through it?
which structures pass through the tarsal tunnel?
Tom, Dick a Very Nervous Harry
Tibialis anterior tendon flexor Digitorum longus tendon posterior tibial Artery and Veins tibial Nerve flexor Hallicus longus tendon
