Lower Limb 4 Flashcards
What is the popliteal fossa?
Fat filled, diamond shaped space posterior to the knee joint
What are the borders of the popliteal fossa?
Upper medial - semimembranosus
Upper lateral - biceps femoris
Lower - medial and lateral heads of gastroc
What are the contents of the popliteal fossa?
Fat
Posterior cutaneous nerve of the thigh
Tibial and common fibular nerves
Popliteal artery and vein and their branches
Termination of the small saphenous vein
Popliteal lymph nodes and lymphatic vessels
What is a popliteal aneurysm?
Abnormal dilatation of part/all of the popliteal artery
Collectively the muscles of the posterior compartment of the leg do what?
Plantarflex and invert the foot
What muscles are in the superficial posterior leg group?
Gastrocnemius
Plantaris
Soleus
What is the action of gastrocnemius?
Flexes the ankle and the knee
Essential for a walking gait
What innervates the posterior compartment of the leg?
Tibial nerve
What is the action of plantaris?
Weakly assists the gastrocnemius in plantarflexing the ankle
Function mainly proprioceptive
What artery supplies all the muscles of the posterior compartment of the leg?
What is it a branch of?
Posterior tibial artery
Branch of popliteal artery
What are the deep muscles of the posterior compartment of the leg?
Popliteus
Tibialis posterior
Flexor digitorum longus
Flexor hallicus longus
What is the action of popliteus?
Weak knee flexor
What is the action of tibialis posterior?
Unlocks knee from extended position, plantar flexes ankle, inverts foot
What is the action of flexor digitorum longus?
Flexes 4 digits, plantarflexes ankle
What is the action of flexor hallucis longus?
Flexes big toe, weakly plantar flexes the ankle
Where do all the posterior leg muscles pass?
(Apart from popliteus) pass to sole of foot posterior to the medial malleolus
How can you remember the structures passing behind the medial malleolus?
Tom - posterior tibialis Dick - flexor digitorum longus And - posterior tibial artery Very - posterior tibial vein Nervous - tibial nerve Harry - flexor hallucis longus
What is the function of the foot?
Supports body weight, plays role in locomotion
What are the tarsal bones?
Calcaneus, talus, navicular, cuboid, intermediate, medial and lateral cuneforms
What is plantar fasciitis?
Presenting as heel pain generally brought on by overuse (e.g. running) or increase in weight
Where does eversion/inversion occur?
Subtalar joints
Ball and socket joint between the talus and navicular allow foot to pivot from side to side
Joint between the talus and calcaneus allow the foot to slide from side to side
Some movement also at traverse tarsal joints
Why is inversion/eversion important?
For coping with walking on uneven ground/balancing on one leg
Muscles of the foot are arranged into how many layers?
4
What is the action of the muscles of the foot?
Flexion of the toes - essential for the push off the ground phase of the gait cycle
What muscles are in layer 1 of the foot and what is this layer deep to?
Deep to plantar fascia
Abductor hallucis
Flexor digitorum brevis
Abductor digiti minimi
What muscles are in layer two of the foot?
Quadratus plantae
Lumbricals
Tendons of FDL also pass through this layer
What do the lumbricals attach to?
FDL
What is the nervous supply to the foot?
Two terminal branches of the tibial nerve - the medial and lateral plantar nerves
What is the arterial supply to the foot?
Posterior tibial artery terminal branches - medial and lateral plantar arteries
What are the arches of the foot?
2 longitudinal
1 transverse
What is the function of the arches of the feet?
Distribute body weight and act as shock absorbers
Body weight acting vertically downwards on the talus forces the navicular and calcaneus apart
Force resisted by muscle tendons crossing the joint and the calcaneonavicular ligament (spring ligament)
What does the spring ligament do?
Help maintain the medial longitudinal arch and contributes to the subtalar joints
What are the passive factors maintaining the integrity of the foot arches?
Shape of united bones
Plantar aponeuosis
Long plantar ligament
Short plantar ligament
What are the dynamic factors maintaining the integrity of the foot arches?
Intrinsic muscles of the foot
Long flexor tendons
Tendon of tibialis anterior and fibularis longus
What is pes planus due to?
Dysfunction of the dynamic or passive factors maintaining the integrity of the foot arches