*****5555 Knee and Lower Leg!

distal end of femur: blue

lateral supracondylar line

distal end of femur: green

medial supracondylar line

distal end of femur:

popliteal fossa

distal end of femur: red

intracondylar fossa

distal end of femur: purple

medial epicondyle (doesn’t articulate with the tibia)

distal end of femur: pink

lateral epicondyle (doesn’t articulate with the tibia)

distal end of femur: yellow

lateral condyle (smooth parts that articulates with the tibia)

distal end of femur: black

medial condyle (smooth parts that articulates with the tibia)

distal end of femur: light green

adductor tubercle (on medial side)

distal end of femur: orange

patellar surface

proximal end of tibia: blue

medial condyle (articulates with condyles of the femur)

proximal end of tibia: green

lateral condyle (articulates with condyles of the femur)

proximal end of tibia:

tibial intercondylar eminence

proximal end of tibia:

Gerdy’s tubercle (is lateral)

proximal end of tibia: red

tibial tuberosity (right above where tibia and fibula articulate)

proximal end of tibia:

shaft

proximal end of tibia: orange

medial malleolus (because tibia will always be lateral to the fibula!)

fibula: blue

head

fibula: green

shaft

contents of popliteal fossa

• popliteal artery

• popliteal vein

• tibial nerve

• common fibular nerve

borders of popliteal fossa

• supralaterally: biceps femoris

• supramedially: semimembranosus

• infralaterally: lateral head of gastrocnemius

• inframedially: medial head of gastrocnemius

review of knee joint

• femorotibial joints (lateral and medial): between the lateral and medial condyles of the femur and tibia

• femoropatella joint: between the patella and femur

fibula is positioned slightly __ and __ to the tibia

posterior; lateral

joint capsule and ligaments

• menisci: fibrocartilage plates located on the articular surface of the tibia

  • function: deepen the tibial surface and act as a shock absorber

    • lateral

    • medial

joint capsule and ligaments: collateral ligaments

• collateral ligaments: during knee extension, the ligaments are taut and during knee flexion, they are loose (which allows for a little rotation)

  • tibial or medial collateral ligament:

    • fused to the joint capsule and the meniscus

    • function: stabilize the knee joint during knee ROM

  • fibular or lateral collateral ligament:

    • attaches into the head of the fibula

    • not fused to joint capsule or meniscus- so more flexibility

    • function: stabilize the knee joint during knee ROM

joint capsule and ligaments: cruciate ligaments

• intra-articular ligaments

  • anterior cruciate ligament:

    • function: provide stability and prevent hyperextension

  • posterior cruciate ligament:

    • stronger and thicker than the anterior

    • function: prevent hyperextension of the knee joint and when weight bearing on a flexed knee, it helps to stabilize the femur, especially when walking down a steep hill

femoropatella articulation and ligament

patellar ligament: begins at the distal end of the quadriceps tendon and crosses over and attaches to the patella and then crosses over and attaches into the tibial tuberosity

additional knee joint supports

• medial

  • pes anserinus: this is the insertions of the sartorius, gracilis, and semitendinous

  • medial head of the gastrocnemius

• lateral

  • iliotibial tract

  • biceps femoris insertion on head of fibula

  • lateral head of gastrocnemius

muscles of the anterior compartment

dorsiflexion

• tibialis anterior (TA)

• extensor hallucis longus (EHL)

• extensor digitorum longus (EDL)

• fibularis tertius

muscles of anterior compartment: white; proximal attachment, distal attachment, innervation, main actions

tibialis anterior (TA)

• proximal attachment

  • lateral condyle

  • tibia

  • interosseous membrane

• distal attachment

  • medial cuneiform

  • base of 1st metatarsal

• innervation

  • deep fibular nerve

• main actions

  • dorsiflexes ankle joint

muscles of anterior compartment: blue; proximal attachment, distal attachment, innervation, main actions

extensor hallucis longus (EHL)

• proximal attachment

  • anterior surface of fibula

  • interosseous membrane

• distal attachment

  • dorsal base of distal phalanx of great toe

• innervation

  • deep fibular nerve

• main actions

  • extends great toe

  • dorsiflexes ankle joint

muscles of anterior compartment: green; proximal attachment, distal attachment, innervation, main actions

extensor digitorum longus (EDL)

• proximal attachment

  • lateral condyle of tibia

  • anterior surface of fibula

  • interosseous membrane

• distal attachment

  • middle and distal phalanges of lateral 4 digits

• innervation

  • deep fibular nerve

• main actions

  • extends lateral 4 digits

  • dorsiflexes ankle joint

muscles of anterior compartment: red; proximal attachment, innervation, main actions

fibularis tertius

• proximal attachment

  • anterior surface of fibula

  • interosseus membrane

• innervation

  • deep fibular nerve

• main actions

  • dorsiflexes ankle joint

  • eversion

muscles of the lateral compartment: fibularis longus (FL); proximal attachment, distal attachment, innervation, main actions

• proximal attachment

  • head and lateral surface of fibula

• distal attachment

  • base of 1st metatarsal

  • medial cuneiform

• innervation

  • superficial fibular nerve

• main actions

  • ***evert

muscles of the lateral compartment: fibularis brevis (FB); proximal attachment, distal attachment, innervation, main actions

• proximal attachment

  • lateral surface of fibula

• distal attachment

  • dorsal surface of 5th metatarsal

• innervation

  • superficial fibular nerve

• main actions

  • ***evert

shaft of tibia: blue

lateral surface

shaft of tibia: red

anterior surface

shaft of tibia: green

medial surface

__ of the tibia: purple

fibula notch

tibia: pink

medial tibia plateau

tibia: black

lateral tibia plateau

tibia: orange

intercondylar area and tubercles

tibia: yellow

soleal line

tibia: light green

nutrient foramen —> nutrient canal —> medullary —> (marrow) cavity

tibia: brown

groove of the tibialis posterior tendon

fibula:

neck

fibula:

lateral malleolus

borders of the femoral triangle

superior boder: inguinal ligament

lateral border: sartorius

medial border: adductor longus

contents of the femoral triangle (lateral to medial)

NAV AL

• femoral nerve

• femoral artery

• femoral vein

(adductor longus border)

adductor canal

• passageway for femoral artery and vein to be delivered down to the popliteal fossa

• start anterior —> ends up going posterior

  • starts at the apex of femoral triangle

    • where they are the femoral artery and vein

  • roof is sartorius

  • goes underneath down to adductor hiatus

    • where they become the popliteal artery and vein

  • bounded posteriorly by the adductor magnus

__ ligament

posterior cruciate ligament

__ ligament

anterior cruciate ligament

tibia:

articular surface

tibia:

fibular notch