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)