Lower limb 4 - The leg Flashcards
What is the tibia?
One of the long bones of the leg.
It is triangular in cross section having medial, lateral and posterior surfaces.
Where is the most common sites for acute osteomyelitis?
upper end of tibial shaft
What is acute osetomyelitis?
infection/inflammation of the bone
Why is the tibia the commonest long bone to be fractured and to suffer compound injury?
the shaft of the tibia is subcutaneous and unprotected anteromedially throughout it’s course and is particularly slender in its lower third.
Why is the tibia a highly accessible donor site for bone grafts?
Due to it’s extensive subcutaneous surface
What is the fibula?
second long bone present in the leg
What is the interosseous membrane? (3)
a form of fibrous joint which unites the tibia and fibula
it separates the muscles of the anterior and posterior compartment of the leg
provides a site for muscle attachment
What is the function of the 2 foramina in the interosseous membrane?
Upper foramina - allows passage of anterior tibial vessels
Lower foramina - allows the passage of anterior perineal vessels
What four muscles are involved in the anterior compartment of the the leg?
- tibialis anterior
- extensor digitorum longus
- extensor hallucis longus
- fibularis tertius
What is the function of the retinaculum in a limb?
a band structure that holds the organ part in place
What are the anterior compartment muscles primarily involved in?
extension at joints
What is the most medial muscle in the anterior compartment of the leg?
tibialis anterior
What are the extrinsic extensors of the toes?
extensor hallucis longus
extensor digitorum longus
Where is the fibularis (peroneus) tertius found and is it present in all individuals?
deep to extensor hallucis longus
How is the anterior tibial artery exposed?
by retracting the extensor digitorum longus
Where does the anterior tibial artery arise from and where does it pass from?
the popliteal artery
from the posterior and anterior compartment of the leg via a hiatus in the interosseous membrane
What is the deep fibular nerve a branch of and what muscles of which compartment does it innervate?
branch of common fibular nerve
innervates muscles of the anterior compartment
What are the two muscles in the lateral compartment of the leg?
- fibularis (peroneus) longus
2. fibularis (peroneus) brevis
What are the fibular muscles tightly invested with and where do their tendons pass?
with the deep fascia of the leg
their tendons pass posterior to the lateral malleolus
Why is the common fibular nerve vulnerable to injury?
as it courses around the neck of the fibula which an area that is vulnerable to fracture
What are the consequences of injuring the common fibular nerve at this point? (6)
- lose ability to dorsiflex foot at ankle joint
- foot drop (foot appears permanently plantar flexed)
- foot drop gait
- loss of sensation over dorsum of foot
- loss of sensation on lateral side of leg
- innervation is preserved on medial side of the leg
What is the posterior compartment of the leg divided into and what by?
superficial sub-compartment
deep sub-compartment
by transverse inter muscular septum
What artery and nerve does the deep sub-compartment of the posterior compartment of the leg contain?
posterior tibial artery
tibial nerve
What are the four muscles involved in the deep sub-compartment of the posterior compartment of the leg?
- popliteus
- flexor digitorum longus
- flexor hallucis longus
- tibialis posterior
Where do the tendons of tibialis posterior, flexor digitorum longus and flexor hallucis longs pass?
pass posterior to the medial malleolus
order - Tom Dick and Nervous Harry
Where do the tibial nerve and posterior tibial artery pass in relation to the medial malleolus, flexor digitorum longs and flexor hallucis longs?
posterior to medial malleolus
between flexor digitorum longus
Flexor hallucis longus
Tom, Dick and Nervous Harry
