Knee (506-518)

Question 1

Name two characteristic features of the medial and lateral menisci;

Answer 1

Meniscis is avascular expect for periphery (outer third).
Medial menisci- larger, attached to medial collataeral ligament.
Lateral menisci- small, not attached to collateral ligament.

Question 2

Name the attachments of the anterior and posterior cruciate ligaments;

Answer 2

Anterior- attaches at the anterior intercondylar region of tibia. Ascends posteriorly to attach to femur in the intercondlyar fossa. (Prevents anterior dislocation of the tibia onto the femur).
Posterior- attaches the anterior lateral surfae of the medial femoral condyle. Descends posteriorly to the posterior intercondylar surface of the tibia. (Prevents posterior disolation of tibia onto the femur)

Question 3

Name the attachments of the medial and lateral collateral ligaments;

Answer 3

Medial- attaches to medial epicondyle of femur, Inserts to medial condyle of tibia.
Lateral- attaches to lateral epicondyle of femur, inserts to depression on the lateral surface of fibular head.

Question 4

What is the difference in clinical presentation between patients presenting with meniscal and cruciate ligament injuries?;

Answer 4

Both twisting injuries. Meniscal tear- ‘tearing’ sensation, knee swells slowly over 6-12 hours, knee may be locked in flexion (unable to extend).
Cruicate- ‘pop’ sensation, rapid joint swelling, positive Lachman’s or anterior draw test.

Question 5

What arrangement of structures within the knee joint would you encounter during arthoscopic surgery (from anterior to posterior)?;

Answer 5

1. Transverse ligament.
2. Anterior horn of medial meniscus.
3. ACL.
4. Anterior horn of lateral meniscus.
5. Posterior horn of lateral meniscus.
6. Posterior horn of medial meniscus.
7. PCL.

Question 6

Name the boundaries of the popliteal fossa;

Answer 6

Superiomedial- semimembranosus (mostly) & semitendinosus.
Superolateral- biceps femoris.
Inferomedial- medial head of gastrocnemis.
Inferolateral- lateral head of the gastrocnemius and plantaris.

Question 7

Name the contents of the popliteal fossa;

Answer 7

Popliteal artery [continuation of femoral artery] (deepest),
Popliteal vein.
Tibial nerve.(most superficial)

Common fibular (peroneal) nerve (laterally).

[Notes tibial nerve and common fibular are bifurcation of sciatic nerve which bifurcates at top of popliteal fossa)

Question 8

Name four differential diagnoses for a swelling in the popliteal fossa;

Answer 8

Baker’s cyst (inflammation and swelling of the semimbranosus bursa - sac containing small amount of synovial fluid - usually self-resolves, can rupture). Popliteal aneurysm (can compress tibial nerve resulting in weakened or absent plantar flexion + paraesthesia of the foot and posterolateral leg). DVT. Neuroma. Lipoma.

Question 9

Where is the long saphenous vein found in the leg?;

Answer 9

Formed by dorsal venous arch of foor and great toe. Ascends up medial side of leg, passing anteriorly to medial malleolus at ankle and posteriorly to the medial condyle at knee.

Question 10

Into where does the long saphenous empty?;

Answer 10

Great saphenous vein terminates by draining into the femoral vein immediately inferior to inguinal ligament.

Question 11

Which nerve accompanies the long saphenous vein?;

Answer 11

Saphenous nerve (sensory only - to anteromedial leg )- largest cutaneous branch of the femoral nerve.

Question 12

Where is the short saphenous vein found in the leg and where does it empty?;

Answer 12

Formed by dorsal venous arch of foot and little toe. Moves up the posterior side of leg, passing posteriorly to lateral malleolus.
At knee, the short saphenous vein passes between two head of the gastrocnemius muscles and empties into the popliteal vein in the popliteal fossa.

Question 13

Which nerve accompanies the short saphenous vein?;

Answer 13

Sural nerve (sensory only to posterolateral leg to lateral ankle)- made forom union of cutaneous nerves (branches of common fibular and tibia nerve)