Flashcards in MSK - The Popliteal Fossa Deck (19):
What are the four borders of the popliteal fossa?
- Superiomedial border = Semimembranous
- Superiolateral border = Biceps femoris
- Inferiomedial border = Medial head of the gastrocnemius
- Inferiolateral border = Lateral head of the gastrocnemius and plantaris
What is the roof and what is the floor of the popliteal fossa?
- Roof = Popliteal fascia (continuous with fascia lata) and skin
- Floor = Posterior surface of the knee joint capsule
What are the contents of the popliteal fossa? (Medial to lateral please)
- Popliteal artery
- Popliteal vein
- Tibial nerve
- Common fibular nerve
What is the most superficial of the contents of the popliteal fossa?
- Tibieal and common fibular nerves (branches of the sciatic nerve)
- Common fibular follows biceps femoris tendon
How does the small saphenous vein enter the popliteal fossa?
- Pierces the popliteal fascia of the popliteal fossa
- Drains into the popliteal vein
What is the deepest of the contents in the popliteal fossa?
Popliteal artery (continuation of the femoral artery)
What is a baker's cyst?
- Popliteal cyst
- Inflammation of the semimembranous bursa
How do baker's cysts arise? What can happen to them?
- Usually with arthritis of the knee (rheumatoid or osteo)
- Can rupture and produce symptoms similar to DVTs
What is a popliteal aneurysm?
- Dilation of the artery (increases by 50%)
What can happen as a result of a popliteal aneurysm?
- Compresses other contents
- Tibial nerve is most susceptible to compression by popliteal artery
- Damage presents as leg anesthesia/loss of function
How can a popliteal aneurysm be detected?
- Palpable pulsation in the popliteal fossa
- Abnormal arterial sounds
What are the borders of the adductor canal?
- Anterior = Sartorius
- Lateral = Vastus medialis
- Posterior = Adductor longus and adductor magnus
What marks the apex of the adductor canal?
Adductor hiatus (gap between the adductor and hamstring attachments of the adductor magnus)
What is the function of the adductor canal?
Acts as a passageway for structures passing between the anterior thigh and posterior leg
What are the contents of the adductor canal?
- Femoral artery
- Femoral vein
- Nerve to vastus medialis
- Saphenous nerve
What is an adductor canal block?
- Administration of local anaesthetic to block saphenous vein (and sometimes nerve to vastus medialis)
Why are adductor canal blocks used?
- Provide sensory anaesthesia for distal thigh/femur, knee and medial lower leg procedures
How is the saphenous nerve located?
Use sartorius and femoral artery as landmarks