Download HBS2ALT topic three: leg, learning outcomes for flag test 3

HBS2ALT topic three: leg, learning outcomes for flag test 3
LEG
General
1. Defi e leg a d des ri e its relatio ship to the thigh, popliteal fossa a d foot. Explai the use of the ter s alf
a d shi
- the leg refers to the potion of the lower limb that is distal to the knee joint
complex and proximal to the ankle joint and foot
- It sits below the thigh and popliteal fossa, with two of the leg muscles
forming the inferomedial and inferolateral boundaries of the popliteal fossa
(medial and lateral gastrocnemius heads)
- CALF: generally refers to the superficial muscles of the posterior
muscle
compartment contents
o These muscles sit posterior to the tibia and fibula
o Incorporates the triceps surae muscle group and sural nerve
- SHIN: the anterior border and medial aspect of the tibial shaft, as well
as the
patella ligament and quadriceps tendon
2.
Compare and contrast the roles of the tibia and the fibula in the leg
- TIBIA
o the primary weight bearing bone of the leg
 carries 90% of body weight
o also serves as muscle and ligament attachment site
o articulates with femur to form knee joint complex
proximally
o articulates with fibula proximally and distally
o articulates with fibula and talus to form talocrural joint
(a.k.a ankle joint)
- FIBULA
o Carries very little body weight
 Around 10%
o Serves as a major site for muscle and ligament attachment
in the leg
o articulates with tibia and talus to form talocrural joint (a.k.a ankle joint)
3. Describe extrinsic and intrinsic muscles of a region. Explain why most of the muscles of the leg can be described as
extrinsic muscles of the foot.
- INTRINSIC muscles are those that exist in their entirety within one region
o i.e. muscles intrinsic to the foot originate and insert within the foot
- EXTRINSIC muscles are those that originate in a different region from the one they insert into
o most leg muscles are considered extrinsic as they originate in the leg region, but insert into the foot
Relationships of the deep fascia
4. Apply M15 and M16 to define the boundaries of the three muscular compartments of the leg with reference to
relevant bones, crural fascia, intermuscular septa, transverse fascia and the interosseous membrane. State the
common function, innervation and blood supply of each of the compartments of the leg.
M15: muscles of a common function are usually located together in a muscle compartment, innervated by the
same nerve and sharing common arterial supply and venous drainage
M16: muscle compartments of a limb may be bounded by bone and/or deep fascia
-
ANTERIOR COMPARTMENT
o Borders
 Medially: lateral tibial shaft
 Posteriorly: interosseous membrane
 Laterally: medial fibular shaft and anterior intermuscular septum
 Anteriorly: crural fascia
o Common actions: dorsiflexion (true extension)
o
o
-
Common vascularisation: anterior tibial artery and vein
Common innervation: deep peroneal nerve
LATERAL COMPARTMENT
o Borders
 Medially: lateral fibular shaft
 Posteriorly: posterior intermuscular septum