Knee and Ankle Flashcards
Osteology of the knee and ankle
distal femur
patella
tibia
foot
Landmark of the distal femur
femoral condyles
landmarks of the tibia
medial and lateral condyles
tibial tuberosity
medial malleolus
landmark of the fibula
head
lateral malleolus
landmark of the foot
calcaneous talus tarsals metatarsals phalanges
Joints of the knee
knee - femorotibial
tibiofibular
-tibiotalar
Joints of the foot
MTP - metarsophalangeal
PIP - proximal interphalangeal
DIP - distal interphalangeal
What type of joint is the knee joint?
hinge joint: primarily flexion and extension
Articulation of the knee
lateral and medial femorotibial
femoropatellar
quadriceps femoris strengthens the joint
How does the knee “lock”?
extension and medial rotation of the knee
Function of locking the knee
tightens ligaments to reduce energy needed for standing
how is joint stability increased in the knee?
flatter surfaces of the femur into contact with tibial plateau
What causes unlocking of the knee?
Popliteus muscle which initiates lateral rotation of the femur on the tibia
Extracapsular ligaments of the knee
patellar
fibular collateral
tibial collateral
Intracapsular ligaments of the knee
anterior cruciate ligament
posterior cruciate ligament
lateral menisci
medial menisci
ACL
anterior cruciate ligament
prevent anterior displacement of tibia on femur
PCL
prevents posterior displacement of tibia on femur
Lateral and medial menisci
increase joint congruency and absorb shock
How are the cruciates named?
criss cross; named for where they attach on tibial plateau
Clinical correlates of the knee
When the foot is in a fixed position and twisting motion occurs, you can have a compounded knee injury such as a torn ACL, TCL, and medial meniscus.
Anterior drawer sign
pull knee forward and grade the amount of translation
ACL tear
posterior drawer sign
push knee posteriorly and grade amount of translation
PCL tear
What is Osgood-Schlatter’s Disease?
rupture of growth plate at the tibial tuberosity
Osgood-Schlatter’s Disease is common in what population?
9-16 yo, especially boys
active
What causes Osgood-Schlatter’s Disease?
stress on the patellar tendon
Function and location of knee joint bursae
prepatellar and infra patellar
allows skin to move easily and permits smooth movement
~12
Branches of the genicular anastomosis
popliteal artery and femoral artery branches to the:
superior lateral genicular a. inferior lateral genicular a. superior medial genicular a. middle genicular a. inferior medial genicular a.
what type of joint is the ankle joint?
hinge (mostly flexion and extension); synovial
Lateral ligament of the ankle is composed of:
anterior talofibular ligament
posterior talofibular ligament
calcaneofibular ligament
Function of the medial and lateral ligaments
stabilize ankle during inversion and eversion
Compartments of the lower leg
Anterior
Lateral
Superficial posterior
Deep poster
What are the compartments of the lower limb separated by?
inter muscular septa
What is compartment syndrome?
increased pressure within the compartments of the limbs
What happens during compartment syndrome?
compression of nerves and blood supply which leads to ischemia
How to fix compartment syndrome?
fasciotomy
Superficial drainage of the lower limb: medial
great saphenous vein
Superficial drainage of the lower limb: posterior
small saphenous vein
Superficial drainage of the lower limb: deep
follow arteries in the vascular sheath and usually paired
popliteal v. –> femoral vein –> external iliac
Where are perforating veins?
between the superior and deep veins
they have valves that flow superficial to deep only
Musculovenous pump
active pumping of the leg muscles to pump blood back to the heart
What happens if there is a problem with the Musculovenous pump?
venous insufficiency and varicose veins
four muscles of the posterior thigh
Semitendinosus
Semimembranosus
Biceps femoris Long head
Biceps femoris (short head)
Action of the muscles of the posterior thigh
flex knee
bones of the leg
tibia and fibula
how are the bones of the lower leg connected?
interosseous membrane
Function of the anterior compartment of the lower leg
ankle dorsiflexion
toe extension
foot inversion
innervation of the anterior compartment of the lower leg
deep fibular nerve
blood supply of the anterior compartment of the lower leg
anterior tibial a.
Function of the lateral compartment of the lower leg
foot eversion
innervation of the lateral compartment of the lower leg
superficial fibular nerve
blood supply of the lateral compartment of the lower leg
fibular a.
muscles of the anterior compartment of the lower leg
tibialis anterior
extensor digitorum longus
extensor hallicus longus
muscles of the lateral compartment of the lower leg
fibularis longus
fibularis brevis
function of the posterior compartment of the lower leg
ankle plantarflexion
toe flexors
muscles of the superficial posterior compartment of lower leg
gastrocnemius
soleus - deep to gastric
plantaris - superior
(triceps surae)
muscles of the deep posterior compartment of lower leg
flexor digitorium longus
flexor hallicus longus
tibialis posterior
popliteus
innervation of the posterior compartment
tibial n.
blood supply of the posterior compartment
posterior tibial a.
fibular a.
What is the popliteal fossa?
diamond shaped area that is bounded by:
semimembranosus
biceps femoris
heads of gastrocnemius
contents of the popliteal fossa
popliteal a. popliteal v. anterior and posterior tibial a. tibial n. common fibular n. lymph nodes
importance of popliteal fossa
popliteal pulse
Retinacula of the foot
synovial sheaths
(keeps the nerves and muscles in place)
extensor retinacula
fibular retinacula
flexor retinaculum
Tarsal tunnel
Flexor retinaculum
“Tom, Dick, and Harry”
tibialis posterior, flexor digitorum longus, tibial nerve, flexor hallicus longus
Sole of the foot
plantar fascia
plantar aponeurosis
compartments of the sole
medial central and lateral
Who is at risk for DVT?
post operative patients
use compression to aid venous return
innervation of the foot
medial and lateral plantar n.
deep fibular n.
blood supply of the foot
terminal branches of the anterior and posterior tibial a.
clinical importance of the foot
dorsal pedis artery
pulse point
nerves of the leg
saphenous n.
sciatic n.
saphenous nerve
(branch of femoral n.) (L2-L4) – skin of medial leg/foot
sciatic nerve
anterior, posterior and lateral leg, foot
splits into: tibial n., common fibular n.
What is deep vein thrombosis?
blood clot develops in vein of leg and can travel to the heart/lungs resulting in pulmonary embolism
