Anterior leg Flashcards
Muscles of anterior leg
Extensor digitorum longus
Extensor hallucis longus
Tibialis anterior
Insertions medial to lateral
THUD
Tibialis anterior
Extensor hallucis longus
Extensor digitorum longus
Tibialis anterior
Origin
Insertion
Action
Innervation
Origin: lateral tibia
Insert: Medial cuniform and base of metatarsal 1 (2)
Actions: Dorsiflexion and inversion of foot
Innervation: Deep fibular nerve
Extensor digitorum longus
Origin
Insertion
Action
Innervation
origin: lateral condyle of tibia and medial surface fibula
The fibres converge into a tendon, which travels onto the dorsal surface of the foot.
Insert: Tendon splits into 4 inserting onto 4 lateral toes
Action: Extension of lateral 4 toes, dorsiflexion of foot
Innervation: Deep fibular nerve
Extensor hallucis longus
Origin
Insertion
Action
Innervation
Origin: Medial surface of fibular shaft
Insert: Crosses anterior ankle and attaches to base of distal phalanx of big toe
Actions: Extension of big toe, dorsiflexion of foot
Innevation: Deep fibula nerve
Clinical relevance of anterior leg muscles
Paralysis or weakness of them can lead to foot drop
What is foot drop?
Inability to dorsiflex the foot at the ankle joint – resulting in the foot “dropping” under the influence of gravity.
What does foot drop indicate?
- Weakness or paralysis of muscles in anterior compartment of leg
Foot drop is often a result of damage to which nerve?
- Common fibula nerve (peroneal nerve) which branches into deep and superficial fibular nerves
What happens to the posterior leg muscles as a result of foot drop?
result in permanent plantar flexion of posterior leg muscles
What is typically sen in the walk of someone with foot drop?
Eversion flick - where the patient flicks the foot while walking
Why do patients result in eversion flick?
Because The inability to dorsiflex the foot can interfere with walking – as the affected foot drags along the ground. To circumvent this, the patient can flick the foot outwards while walking – known as an ‘eversion flick‘.
Neurovascualr supply
Deep fibular (peroneal) nerve Anterior tibial artery/vein