Leg: Bones and Muscles Flashcards
What is the most common site of a compound fracture?
the medial surface of the tibial shaft because it is subcutaneous
What are the borders of the anterior compartment of the leg?
the tibia, the interosseus membrane, the anterior intermuscular septum and the encircling deep fascia
What are the muscles of the anterior compartment of the leg?
tibialis anterior, extensor hallicus longus, extensor digitorum longus
What is the origin of the muscles of the anterior compartment of the leg?
the shaft of the bone they overly and the adjacent interosseus membrane
What is the action of tibialis anterior?
dorsiflexion and inversion
What is the insertion of tibialis anterior?
base of the 1st metatarsal and the medial cuneiform
What is the insertion of extensor digitorum longus?
each of the 4 tendons splits into 3 parts and the lateral parts insert distally and the medial part inserts proximally
What is fibularis tertius?
a muscle which splits off from extensor digitorum longus to insert on the base of the 5th metatarsal
What is the order of the structures as they pass underneath the extensor retinaculum?
TA, EHL, anterior tibial artery, deep fibular nerve, EDL, FT
What are the boundaries of the lateral compartment of the leg?
the anterior and posterior intermuscular septa, the fibula and the deep encircling fascia
What are the muscles of the lateral compartment of the leg?
fibularis longus and brevis
What is the action of the muscles of the lateral compartment of the leg?
eversion
What is the origin of fibularis longus?
the proximal part of the shaft of the fibula
What is the origin of fibularis brevis?
the distal part of the shaft of the fibula
Which tendon of fibularis longus and brevis passes closer to the lateral malleolus as they pass behind the lateral malleolus?
fibularis brevis
What is the insertion of fibularis brevis?
the base of the 5th metatarsal (with fibularis tertius)
What is the insertion of fibularis longus?
medial cuneiform and the base of the 1st metatarsal (with tibialis anterior) - tendon has to go under the foot and so helps to maintain the arch of the foot
What are the parts of the fibular retinaculum?
superior and inferior
What are the borders of the posterior compartment of the leg?
the tibia, the fibula, the interosseus membrane, the posterior intermuscular septa
What are the muscles of the deep compartment of the posterior compartment of the leg?
tibialis posterior, flexor hallicus longus, flexor digitorum longus
What are the muscles of the superficial compartment of the posterior compartment of the leg?
gastrocnemius, soleus, popliteus, plantaris
What is the origin of gastrocnemius?
the condyles of the femur
What is the insertion of gastrocnemius?
calcaneus (via the achilles tendon)
What is the origin of soleus?
the soleal line
What is the insertion of soleus?
calcaneus (via the achilles tendon)
What is the origin of plantaris?
next to the lateral head of gastrocnemius on the femoral condyle
What is the action of tibialis posterior?
plantar flexion and inversion
What is the order of structures passing behind the flexor retinaculum?
from the medial malleolus back - TP, FDL, posterior tibial artery, posterior tibial vein, tibial nerve, FHL
What is the insertion of tibialis posterior?
medial cuneiform and the base of the 1st metatarsal
Why do the tendons of FHL and FDL cross?
because they are on the wrong sides of the compartment so the tendons have to cross to reach their site of insertion
