10/03/2021 [leg muscles, leg dermatomes, disc prolapse, physiology of immnunity, rheumatic fever, sarcoidosis, inhaler use, uveitis, anatomy of the eye, Bechette's disease, Omdamzatron] Flashcards
(112 cards)
Muscles int he anterior compartment of the leg?
Tibialis anterior, extensor digitorun longus, exntensor hallucis longus and fibularis tertius
Collectively what do the anterior leg muscles do?
Dorsiflex and invert eh footy at the ankle joint
Whihch muscles extend the toes
Extensor digitorum longus and extensor hallucis longus
Innervation of the muscles
Deep fibular nerve [L4-S1]
Blood supply anterior muscles leg
Anterior tibial artery
Location, action, attachments, innervation of the tibilias anterio
The tibialis anterior muscle is located alongside the lateral surface of the tibia. Attachments: Originates from the lateral surface of the tibia, attaches to the medial cuneiform and the base of metatarsal I. Actions: Dorsiflexion and inversion of the foot. Innervation: Deep fibular nerve.
Extensor digiroum longus
The extensor digitorum longus lies lateral and deep to the tibialis anterior. The tendons of the EDL can be palpated on the dorsal surface of the foot. Attachments: Originates from the lateral condyle of the tibia and the medial surface of the fibula. The fibres converge into a tendon, which travels to the dorsal surface of the foot. The tendon splits into four, each inserting onto a toe. Actions: Extension of the lateral four toes, and dorsiflexion of the foot. Innervation: Deep fibular nerve
How can you test the power of the tibilias anteiror?
To test the power of the tibialis anterior, the patient can be asked to stand on their heels.
Which is the strongest muscle santerior compartmetn?
Tibilias anterior
Extnesor hallucis longus
The extensor hallucis longus is located deep to the EDL and TA. Attachments: Originates from the medial surface of the fibular shaft. The tendon crosses anterior to the ankle joint and attaches to the base of the distal phalanx of the great toe. Action: Extension of the great toe and dorsiflexion of the foot. Innervation: Deep fibular nerve
Fibularis tertarius
The fibularis tertius muscles arises from the most inferior part of the EDL. It is not present in all individuals and is considered by some texts as a part of the extensor digitorum longus. Attachments: Originates with the extensor digitorum longus from the medial surface of the fibula. The tendon descends with the EDL, until they reach the dorsal surface of the foot. The fibularis tertius tendon then diverges and attaches to metatarsal V. Actions: Eversion and dorsiflexion of the foot. Innervation: Deep fibular nerve
When does footdrop occur? Sx of it
Footdrop is a clinical sign indicating paralysis of the muscles in the anterior compartment of the leg. It typically occurs as a consequence of damage to the common fibular (peroneal) nerve – from which the deep fibular nerve arises. In footdrop, the muscles in the anterior compartment are paralysed. The unopposed pull of the muscles in the posterior leg produce permanent plantarflexion. This can interfere with walking – as the affected limb can drag along the ground. To circumvent this, the patient can flick the foot outwards while walking – known as an ‘eversion flick
Which muscle porduces eversioin of the subtalar joint?
Fibularis tertaius
Muscles in the lateral compartment of the leg
There are two muscles in the lateral compartment of the leg; the fibularis longus and brevis (also known as peroneal longus and brevis)
Function of the muscles in the lateral compartment
The common function of the muscles is eversion – turning the sole of the foot outwards. They are both innervated by the superficial fibular nerve
Attahcments, actions, innervation, location of the fibularis longus
The fibularis longus is the larger and more superficial muscle within the compartment. Attachments The fibularis longus originates from the superior and lateral surface of the fibula and the lateral tibial condyle. The fibres converge into a tendon, which descends into the foot, posterior to the lateral malleolus. The tendon crosses under the foot, and attaches to the bones on the medial side, namely the medial cuneiform and base of metatarsal I. Actions: Eversion and plantarflexion of the foot. Also supports the lateral and transverse arches of the foot. Innervation: Superficial fibular (peroneal) nerve, L4-S1
Fibularis brevis
The fibularis brevis muscles is deeper and shorter than the fibularis longus. Attachments: Originates from the inferolateral surface of the fibular shaft. The muscle belly forms a tendon, which descends with the fibularis longus into the foot. It travels posteriorly to the lateral malleolus, passing over the calcaneus and the cuboidal bones. The tendon then attaches to a tubercle on metatarsal V. Actions: Eversion of the foot. Innervation: Superficial fibular (peroneal) nerve, L4-S1.
How can the common fibular nerve be lcoated?
The common fibular nerve can be a difficult structure to identify. However, it can be located using the fibularis longus as an anatomical landmark. There is a small space between the parts of the fibularis longus that originate from the head of the fibula, and the neck of the fibula. The common fibular nerve passes through this gap, and is easily identified. After passing through the gap, the nerve terminates by bifurcating into two terminal branches; the deep and superficial fibular nerve
Which nerve innervated lateral compartment leg?
Superficial fibular
How is the posterior compartment leg seperated?
The posterior compartment of the leg contains seven muscles, organised into two layers – superficial and deep. The two layers are separated by a band of fascia
Function of the posterior leg muscles? Innervation too.
The posterior leg is the largest of the three compartments. Collectively, the muscles in this area plantarflex and invert the foot. They are innervated by the tibial nerve, a terminal branch of the sciatic nerve
Where do all the calf muscles insert?
The superficial muscles form the characteristic ‘calf’ shape of the posterior leg. They all insert into the calcaneus of the foot (the heel bone), via the calcaneal tendon.
What does the calcaneal reflex test?
nerve roots S1-2
To minimise friction duyring movement, what is located with the calcaneal tendon?
To minimise friction during movement, there are two bursae (fluid filled sacs) associated with the calcaneal tendon: Subcutaneous calcaneal bursa – lies between the skin and the calcaneal tendon. Deep bursa of the calcaneal tendon – lies between the tendon and the calcaneus











