Posterior Leg Flashcards
What are the three thigh compartments and what muscles constitute them?
Anterior - quadriceps femoris
Medial - Sartorius, adductor longus, adductor brevis, gracilis and adductor magnus
Posterior - semi-membranous, semi-tendinosus, and biceps femoris (short and long head)
What is the innervation and function of the anterior thigh compartment?
Femoral nerve and extension at the knee
What is the innervation and action of the posterior thigh compartment?
Sciatic nerve and flexion at the knee
What is the innervation and function of the medial thigh compartment?
Obturator nerve and addiction at the hip
What divides the posterior leg compartments into two groups of muscles?
The transverse septa
Divides the post. Thigh compartments into superficial and deep groups
What muscles are in the superficial posterior leg group?
Gastrocnemius, soleus, and plantaris
What muscles make up the deep posterior leg group?
Popliteus, flexor hallucis longus, flexor Digitorum longus, and tibialis posterior
Which posterior leg muscle crosses the knee and ankle?
Gastrocnemius M
What is the origin of the medial head of the gastrocnemius?
Superior to the medial femoral condyle
What is the origin of the lateral head of the Gastrocnemius M?
Superior to lateral femoral condyle
What is the insertion of Gastrocnemius M.?
Posterior surface of calcaneus via tendo calcaneus (Achilles tendon)
What are the actions of the Gastrocnemius M?
Plantar flexion and flex leg at knee joint
What is a Fabella and what is its clinical manifestation?
A sesamoid bone located in the lateral head of the gastrocnemius that provides leverage for lateral head of the muscle.
Injury could cause stress fracture of the fabella and may accompany total knee replacement
What is the origin of the Soleus M.?
The soleal line of tibia and posterior head of fibula
Where does the Soleus M. Insert?
The posterior surface of calcaneus via tendo calcaneus
What is the triceps surae?
A pair of muscles located in the calf region - the two heads of the gastrocnemius and the surae muscle
What is the action of the soleus m.?
Plantarflexion
What is the origin of plantaris m.?
Lateral end of the lateral supracondylar line
What is the insertion of the plantaris m.?
The posterior surface of calcaneus via calcaneal tendon
What is the action of plantaris?
Weak plantarflexion and leg flexion
Why is the plantaris thought to be a proprioceptive organ for foot position?
Because of the unusually high density of proprioceptive receptor end organs in this muscle
What are the two clinical importances of the plantaris muscle?
The long tendon is commonly used in reconstructive surgery of hand tendons
There is also a possibility of rupture during violent ankle movements (sudden dorsiflexion of ankle joint). It’s a common injury in basketball players, sprinters, and ballet dancers
What is the origin of the popliteus m.?
The lateral surface of the lateral femoral condyle and lateral meniscus
What is the insertion for the popliteus m.?
Posterior tibia (superior to soleal line)
What is the function of the popliteus?
To unlock extended leg by laterally rotating femur on a stationary tibia
Also weakly flexes leg
What are the arteries of the popliteal fossa?
Superior medial and lateral genicular arteries
Inferior medial and lateral genicular arteries
What is the origin of the flexor hallucis longus?
Inferior 2/3 of posterior fibula
What is the insertion of the flexor hallucis longus m?
Base of distal phalanx of great toe
What is the action of the flexor hallucis longus m?
Flexes great toe, plantarflex foot at ankle joint
What is the groove for the flexor hallucis longus tendon?
The space between the medial and lateral tubercle of the talus make a groove for the flexor hallucis longus tendon
What is the calcaneus and what does it articulate with?
It is the largest foot bone and articulates with the talus superiorly and cuboid anteriorly
What is the sustentaculum tali?
Shelf-life projection that supports talus and provides groove for flexor hallucis longus
What is the origin of the flexor digitorum longus?
Posterior tibia (inferior to soleal line)
What is the insertion fo the flexor digitorum longus m.?
Distal phalanx base of lateral four digits
What are the actions of the flexor digitorum longus m?
Flex lateral four digits, plantarflex foot at ankle joint
What is the origin of the tibialis posterior m?
Interosseus membrane, posterior tibia inferior to soleal line and posteromedial surface of fibula
What is the insertion of the tibialis posterior?
Tarsal and metatarsal bones:
Navicular tuberosity
Cuneiforms
2-3 metatarsal bases
What is the action of the tibialis posterior m?
Inversion and plantarflexion
What is the navicular and what does it articulate with?
A tarsal bone that articulates posteriorly with the talus tarsal head, anteriorly with 3 cuneiforms and laterally with the cuboid tarsal
What attaches on the navicular tuberosity?
Tibialis posterior muscle
What is the acronym for the plantar and digital flexors and neurovasculature that you see on the medial side of the ankle?
Tom, Dick and Harry
T - T. Of Tibialis posterior m
D - T. Of flexor Digitorum longus m
(a.n)d - posterior tibial Artery and tibial Nerve
H - T. Of flexor Hallucis longus m
What two support systems make up the dynamic arch of the foot? What is included in those systems?
Dynamic support and passive support
Dynamic includes the tibialis posterior, tibialis anterior, flexor hallucis longus, fibularis longus and intrinsic plantar muscles
Passive support includes the plantar aponeurosis, plantar calcaneonavicular ligament, long plantar ligament and short plantar ligament
What nerve supplies all posterior compartment muscles of leg?
Tibial nerve
What are the spinal nerve levels of the Tibial nerve?
L4-S3
What are the spinal nerve levels of the common fibular nerve?
L4-S2
What does the tibial nerve pass with? How does it leave the posterior compartment?
The posterior tibial vessels. It’s deep to the soleus and posterior to tibialis posterior
It leaves by passing deep to the flexor retinaculum between the medial malleolus and calcaneus
How does the Tibial Nerve terminate?
It ends by dividing into the medial and lateral plantar nerves
What is the blood supply of the posterior compartment?
The posterior tibial artery, which gives rise to the fibular artery
Where does the posterior tibial artery run? How does it end?
Begins near inferior border of popliteus m, posses inferiorly and medially on the posterior surface of the Tibialis posterior m, with the tibial nerve, and runs deep to the flexor retinaculum.
It ends by dividing into the medial and lateral plantar arteries
Where does the fibular artery run? How does it end?
It arises from the tibial artery, begins inferior to the distal border of popliteus m, descends obliquely towards the fibular, under the flexor hallucis longus m
It ends by piercing the interosseus membrane and anastomosing with anterior lateral malleolar artery
What compartments of the leg does the fibular artery vascularize?
The posterior and lateral compartments of leg
What is the clinical importance of the posterior tibial artery and pulse? Where can you find it?
You can feel the posterior tibial pulse between the posterior surface of medial malleolus, medial border of calcaneal tendon, and deep to the flexor retinaculum
Its used to examine patients with occlusive peripheral arterial disease (intermittent claudication), which is a condition caused by reduced blood flow of leg muscles due to narrowing or occlusion of leg arteries.
What is the clinical manifestation of occlusive peripheral arterial disease?
Leg cramps and pain during walking
What are the tarsal bones of the foot?
Calcaneus, talus, cuboid and navicular
What are the bones between the navicular tarsal and first three metatarsals of the foot?
Cuneiforms (3 bones, lateral, intermediate and medial)
What makes up the posterior process of the talus?
The medial and lateral tubercle and the groove for flexor hallucis longus tendon
What separates the posterior deep compartment with the anterior compartment of the leg?
The interosseus membrane
What separates the anterior compartment and the lateral compartment of the leg?
Anterior septum
What separates the lateral compartment and the superficial posterior compartment of the leg?
Posterior septum
What is the crural fascia?
A the fascia around the leg muscles that have anterior, lateral and posterior septum
