knee

Question 1

articulations within the knee

Answer 1

• between patella, femur and tibia
• lined with hyaline cartilage 4 movement nd alleviate friction
• tibiofemoral: medial and lateral condyles of femur articulate with tibial condyle= weight bearing compartment
• patellofemoral: anterior aspect of femur articulate with patella= allow 4 tendon of quad femoris (knee extensor) to be inserted directly over knee= increase efficiency

Question 2

intracapsular ligaments

Answer 2

• external to synovial cavity

ACL= runs diagonally from the anteromedial aspect of the intercondylar area both of the tibial plateau upwards and backwards and inserts onto the posteromedial aspect of the lateral femoral condyle

• PCL= arises from the posterolateral aspect of the medial condyle of the femur and attaches to the posterolateral aspect of the posterior intercondylar area of the tibial plateau

Question 3

extracapsular ligaments

Answer 3

• patella ligament= continuation of quad femoris tendon and stabilises the patella
• lateral collateral ligament= stabilise outer knee
• medial collateral ligament= stabilise inner knee
• oblique popliteal ligament= spans the intercondylar fossa accurate
• arcuate politeal ligament= originate on fibular head and arches up and inwards to posterior side of joint capsule

Question 4

knee joints

Answer 4

suprapatellar bursa= between quadriceps femoris and the femur
prepatellar bursa= between apex of patella and skin
infrapatellar bursa= split into deep and superficial.
deep bursa lies between tibia and patella lig
superficial bursa lies between patella lig and skin
semimembranous bursa= lies posterior of knee joint, between semimembranous muscle and the medial head of gastrocnemius

Question 5

major knee muscles

Answer 5

extension: quadriceps
flexion: hamstrings
lateral rotation: biceps femoris
medial rotation: semimembranous, semitendous, gracilis, sartorius and popliteus

Question 6

main arterial supply

Answer 6

femoral artery
popliteal artery - direct continuation from femoral and supply lower leg
splits into anterior and posterior tibial artery - supply ant and pos compartment of lower leg AND genicular anastomoses - supply knee and wrap around sup and inf

Question 7

main blood supply- veins

Answer 7

S- great saphenous= drain into fem
S- small saphenous = drain into pop
genicular anastomoses has genicular venous plexus = drain into pop

• main drainage of knee from popliteal and genicular venous plexus
• all connect with femoral which receive blood from great saphenous
• all come together to form external iliac vein which enter pelvis
• then join internal= common iliac= inferior vena cava

Question 8

major nerves

Answer 8

• come primarily from sciatic, femoral and obturator nerves
• provide movement, sensation and stability

lumbar plexus -> femoral nerve -> saphenous nerve (runs medially)
- fem nerve arise from lumbar plexus and travel down anterior side of thigh
- branches into saphenous nerve which provide sensory info to lower leg and foot

sacral plexus -> sciatic nerve -> tibial and common peroneal nerve (run posteriorly)
- sciatic run down back of thigh
- split into tibial and common peroneal nerve near knee

• obturator nerve travels through pelvis and medial thigh and supplies medial aspect of the knee joint capsule

Question 9

purpose of patella

Answer 9

sesamoid bones
glides past femur during movement
protects the quad femoris
increase mechanical effect of associated muscles