Lower Limb 4: The Leg Flashcards
What is acute osteomyelitis?
Bone infection caused by bacteria
affects the long bones of the legs
Why is the tibia the commonest long bone to be fractured?
very superficial antero-medially
particularly slender in its lower 1/3
What is a compound injury?
an open fracture
occurs where there is a break in the skin around a broken bone
Function of the interosseus membrane?
unites the tibia and fibula
separates the muscles of the anterior and posterior compartment
serves as a site for muscle attachement
What is the function of the two foramina in this membrane?
to allow anterior tibial vessels through
allow perforating branch of fibular artery through
what are the compartments of the leg and what structures separate them?
Anterior (extensor), Posterior (flexor), Lateral (fibular)
separated by interosseus membrane
2 intermusclar septae between fibula and deep fascia
attachment of deep fascia to periosteum of anterior and posterior borders of the tibia
what are the specific functions of the compartments of the leg?
Anterior - dorsiflex ankle, extend toe, invert foot
Posterior - plantarflex ankle, flex toes, invert foot
Lateral - evert foot
What are the muscles of the anterior compartment of the leg?
Tibialis Anterior
Extensor Digitorum Longus
Extensor Hallucis Longus
Fibularis Tertius (aka Peroneus Tertius)
What is the innervation and blood supply of the anterior compartment of the leg?
Deep Fibular Nerve L4, L5, S1
Anterior Tibial artery
What is the function of a retinaculum in a limb?
Hold tendons in place and stabilise them
What is the origin and insertion of Tibialis Anterior?
Origin: Lateral tibial condyle, upper 2/3 of tibial shaft, interosseus membrane
Insertion: medial and intermediate cuneiform, base of 1st metatarsal
What is the action of Tibialis Anterior?
Dorsiflex ankle
invert foot
support medial arch
What is the origin and insertion of Extensor Hallucis Longus
Origin: Middle medial fibula and interosseus membrane
Insertion: Upper surface of base of distal phalynx of great toe
What is the function of Extensor Hallucis Longus?
Extend big toe
dorsiflex ankle
What is the origin and insertion of Extensor Digitorum Longus?
Origin: Lateral fibular condyle, upper 2/3 medial fibula, interosseus membrane
Insertion: 4 tendons come from inferior extensor retinaculum and extend to middle and distal phalanges of toes 2-5
What is the function of Extensor Digitorum Longus?
Extend toes 2-5
Dorsiflex ankle
Where is Fibularis Tertius?
deep and lateral to extensor hallucis longus and extensor hallucis brevis
this muscle is not present in all individuals
What is the function of Fibularis Tertius?
Assist in dorsiflexion and eversion of the foot