Flashcards in Lower Limb 2: Posterior Thigh and Popliteal Fossa Deck (23):
Where would you find the medial and lateral linea aspera?
Posterior, superior 2/3 of the shaft of the femur
Which is more superior, the epicondyle or the condyle?
Function of the fascia lata?
forms 3 intermuscular septa, separating the thigh into 3 compartments:
anterior extensor (of the leg at the knee)
posterior flexor (flex leg at knee and extend thigh at hip)
medial adductor (thigh at hip)
What are the muscles of the posterior compartment of the thigh? (Hamstrings)
Biceps Femoris (long head)
(Hamstring part of adductor magnus muscle)
What is the common origin of the hamstrings?
What is the innervation of the hamstrings?
Sciatic nerve, tibial division
L5, S1, S2
Where does Semimembranosus insert?
Groove and adjacent bone on posterior surface of medial tibial condyle
Where does Semitendinosus insert?
Medial surface of superior tibia
Where does Biceps Femoris (long head) insert?
Head of fibula
Why is Biceps Femoris (short head) not considered to be part of the hamstrings?
Does not share common origin or innervation
Origin: lateral linea aspera, lateral supracondylar ridge of femur
Insertion: head of fibula
Innervation: Sciatic nerve, Common Peroneal divison (L4-S2)
What are the functions of the hamstrings?
Flex leg at knee
Extend thigh at hip
Biceps femoris rotates laterally
Semi's rotate medially
Why is part of adductor magnus considered to be one of the hamstrings?
Shares the same common origin (ischial tuberosity) and nerve supply of the hamstrings (sciatic nerve, tibial division L5, S1, S2)
Describe the dual innervation of the adductor magnus muscle
Adductor part - Obturator nerve (L2, L3, L4)
Hamstring part - Sciatic nerve, tibial division (L5, S1, S2)
describe the blood supply of the hamstrings
upper part: inferior gluteal artery
Middle (main part): profunda femoris artery and its penetrating branches
Lower part: Popliteal artery
describe the course of the sciatic nerve through the thigh
Descends into the hamstrings, where it divides at a variable point in the leg
Splits into the Tibial division and the common fibular (peroneal) nerve
Common fibular deviates laterally, both enter the popliteal fossa
What forms the floor and roof of the popliteal fossa?
Floor - popliteal surface of femur
- capsule of the knee joint and oblique popliteal ligament
- strong fascia covering popliteus
Roof - skin
- superficial fascia
What are the boundaries of the popliteal fossa?
Supero-lateral: biceps femoris tendon
Infero-medial: medial head of gastrocnemius
Infero-lateral: lateral head of gastrocnemius
How is the posterior compartment of the leg divided?
Divided into a superficial and a deep compartment by the transverse intermuscular septum.
What muscles are in the superficial compartment of the posterior leg?
Which muscle of the posterior leg can act as a flexor of the knee as well as a plantarflexor of the ankle joint?
What does the Tibial nerve innervate?
Supplies all muscles in posterior thigh except short head of biceps femoris
+ supplies hamstring part of adductor magnus
supplies muscles of posterior compartment of the leg
Intrinsic muscles in the sole of the foot except first 2 dorsal interossei
Skin on posterolateral side of lower half of the leg, medial ankle, foot, little toe and skin on sole.
What does the Common Peroneal (fibular) nerve do?
Innervates short head of biceps femoris in post. thigh
all muscles in anterior and lateral compartments of the leg
Extensor digitorum brevis on dorsal foot
first 2 dorsal interossei in sole of foot
skin over lateral leg and ankle + dorsal aspect of foot and toes