Dissection 4- Popliteal Fossa and Posterior Leg Flashcards
What is the popliteal fossa mostly filled with?
Fat
What shape is the popliteal fossa?
Diamond
Where will you find the popliteal fossa?
Posterior to the knee joint
What is the superolateral border of the popliteal fossa?
Biceps Femoris
What is the superomedial border of the popliteal fossa?
Semimembranosus, semitendinosus
What is the inferior border of the popliteal fossa?
Medial and lateral heads of the gastrocnemius
What is the roof of the popliteal fossa?
Popliteal fascia and skin
What nerves pass through the popliteal fossa?
Tibial nerve, common fibular nerve, posterior cutaneous nerve of the thigh
What vessels pass through the popliteal fossa?
Popliteal artery and vein, termination of small saphenous vein
What structures the are not vessels or nerves pass through the popliteal fossa?
Popliteal lymph nodes, plantaris and popliteus muscles
What vessel ends in the popliteal fossa?
Small saphenous vein
Where does the small saphenous vein pass through in the popliteal fossa?
Deep popliteal fascia in the median plane of the limb
Where does the small saphenous vein drain into?
Popliteal vein
The popliteal deep fascia is continuous with what other deep fascias superiorly and inferiorly?
Superiorly- Fascia lata
Inferiorly- Crural fascia
The popliteal fossa contains a major NVB in what plane?
Median
What is contained in the major NVB of the popliteal fossa, from superficial to deep?
Tibial nerve, popliteal vein, popliteal artery
The popliteal vein is a continuation of what vein?
Posterior tibial vein
The popliteal artery is a continuation of what artery?
Femoral artery
Popliteal lymph nodes are closely associated with and located along which other structure?
Popliteal vein
Where does the popliteal artery begin?
Where the femoral artery passes through the adductor hiatus
Where does the popliteal artery end? What does it divide into?
- Inferior border of popliteus
- Anterior and posterior tibial arteries
Where is the popliteal vein formed?
Inferior border of popliteus
Where does the popliteal vein lie in relation to the popliteal artery?
Superficial
Are the popliteal artery and vein in the same fibrous sheath?
Yes
What does the popliteal vein become at the adductor hiatus?
Femoral vein
Where does the small saphenous vein run between?
Posterior aspect of the lateral malleolus to the popliteal fossa
Where in the popliteal fossa do the superficial popliteal lymph nodes lie?
In subcutaneous tissue
Where do the deep popliteal lymph nodes receive lymph from?
Joint capsule of knee, lymphatic vessels that accompany the deep veins of the leg
Popliteal lymphatic vessels follow the femoral vessels to drain into where?
Deep inguinal lymph nodes
Where does the sciatic nerve usually end? What does it divide into?
- Superior angle of the popliteal fossa
- Tibial and common fibular nerves
Which is the most medial and larger branch of the sciatic nerve?
Tibial nerve
While in the popliteal fossa, the tibial nerve gives off branches to which muscles of the leg?
- Soleus
- Gastrocnemius
- Plantaris
- Popliteus
The medial sural cutaneous nerve is derived from what nerve?
Tibial nerve
The medial sural cutaneous nerve combines with what other nerve to form the rural nerve?
Sural communicating nerve
The sural communicating nerve is a branch of which nerve?
Common fibular nerve
What does the sural nerve supply?
Skin on the posterior and lateral leg and the lateral foot
What is the lateral sural cutaneous nerve a branch of?
Common fibular nerve
What does the lateral sural cutaneous nerve supply?
Skin on the lateral aspect of the leg
Which is the smaller and more lateral branch of the sciatic nerve?
Common fibular nerve
The common fibular nerve leaves the popliteal fossa passing superficial to which muscle?
Lateral head of the gastrocnemius
Where does the common fibular nerve wrap around, causing it to be susceptible to injury?
Fibular neck
What branches does the common fibular nerve divide into terminally?
Superficial and deep fibular
The most inferior branches of the posterior cutaneous nerve of the thigh supply where?
Skin over the popliteal fossa
What will be the clinical signs if the common fibular nerve is damaged?
- Dysfunction of the nerve and the muscles it supplies
- Abnormal sensation in the area of skin supplied by the nerve
What fracture is most likely to cause damage to the common fibular nerve?
Fibular neck fractures
To locate the popliteal pulse:
The knee should be flexed to what degree?
What muscles should be relaxed?
- 30 degrees
- Hamstring muscles
What is the other name for the posterior compartment of the leg?
Plantar flexor compartment
What is the largest of the three leg compartments?
Posterior
All the muscles of the posterior compartment of the leg are supplied by what nerve?
Tibial nerve
All the muscles of the posterior compartment of the leg are supplied by what vessels?
Posterior tibial or fibular vessels
The nerve and blood supplies to all of the posterior compartment of the leg run within which sub-compartment?
Deep
Which muscle has two heads and muscle bellies?
Gastrocnemius
What are the heads/bellies of the gastrocnemius muscle known as?
Medial and lateral
The two heads of the gastrocnemius attach to what bone distally via what tendon?
- Calcaneus
- Achilles (calcaneal) tendon
What bony landmark do the heads of the gastrocnemius attach to proximally?
Their respective femoral condyles
The gastrocnemius muscle crosses which two joints?
Knee and ankle
What are the weak and strong actions of the gastrocnemius muscle?
Strong: plantar flexor of ankle
Weak: flexor of knee
What does the soleus attach to proximally?
Neck of fibula and soleal line of tibia
What does the soleus attach to distally? Via what tendon?
Calcaneus via Achilles tendon
Which of the posterior leg muscles has a short belly and a long tendon?
Plantaris
The plantaris muscle is absent in what % of people?
5-10%
What is the proximal attachment of the plantaris?
Lateral supracondylar line of femur
What does the plantaris attach to distally?
Calcaneus via Achilles tendon
What are the superficial posterior leg muscles?
Plantaris, gastrocnemius, soleus
What are the deep muscles of the posterior leg?
Popliteus, flexor hallucis longus, flexor digitorum longus, tibialis posterior
What is the function of the deep muscles of the posterior leg?
Plantarflex the ankles and toes
The tibias posterior assists which other muscle with which other action?
Tibialis anterior with inversion of the foot
Which is bigger, the FHL or FDL?
FHL
Where does the FHL pass to and from?
Inferior surface of the fibular to base of distal phalanx of great toe
Where does the FDL pass to and from?
Posterior surface of tibia to the bases of the distal phalanges of the lateral 4 digits
What is the proximal attachment of the tibias posterior?
Interosseous membrane (posterior surface of tib and fib)
What bones does the tibias posterior attach to distally?
- Navicular
- Cuneiforms
- Cuboid
- Bases of 2-4 metatarsals
From anterior to posterior, in what order to the structures of the posterior compartment of the leg leave the compartment?
(Tendons of…)
- Tibialis posterior
- Flexor digitorum longus
- Posterior tibial artery
- Tibial nerve
- Flexor hallucis longus
When structures leave the posterior compartment of the leg, where do they pass in relation to the medial malleolus?
Posterior
When structures leave the posterior compartment of the leg, where do they pass in relation to the flexor retinaculum?
Deep
What is a thin, triangular muscle in the floor of the popliteal fossa?
Popliteus
What is the function of the popliteal?
Unlock the fully extended knee joint
Where does the popliteus attach proximally?
Lateral condyle of femur
Where does the popliteus attach distally?
Posterior surface of tibia
How should the patients lower limb be in order to perform the ankle jerk reflex?
- Externally rotatated
- Knee flexed
- Ankle dorsiflexed
What would be the normal response of the ankle jerk?
Involuntary contraction of the gastrocnemius and soleus so the ankle slightly plantar flexes
A positive ankle jerk test confirms the function of what?
- The muscles themselves
- Peripheral nerve supply (tibial nerve)
- Central connections at the spinal cord level and above