Posterior Thigh and Popliteal Fossa

Question 1

Posterior Thigh muscles in general: Common proximal Attachment

Answer 1

Ischial Tuberosity

except for the short head biceps femoris

Question 2

Posterior Thigh muscles in general: Common innervation

Answer 2

Tibial division of sciatic nerve

except short head of biceps femoris

Question 3

Posterior Thigh muscles in general: Common functions

Answer 3

Leg flexion at knee

Thigh extension at hip (except short head of biceps femoris)

Question 4

Semitendinosus Muscle

Answer 4

orgin: Ischial Tuberosity
Insertion: anteromedial aspect of superior tibia (pes anserinus

Function: extend the thigh and flex the leg
also medially rotate flexed leg

inn: Tibial division of Sciatic N

Question 5

Pes anserinus

Answer 5

3 fingered conjoined tendon
 (anterior to posterior)
Sartorius M
Gracilis M
Semitendinosus M

insertion from each three compartments

Question 6

Pes Anserine Bursitis

Answer 6

Inflammation of the anserine bursa which is located between the Pes anserinus and the MCL

constant aching pain, aggrevated by activity specifically flexion and internal/medial rotation of the knee

Question 7

Semimembranosus M

Answer 7

Long flat membranous tendon at proximal attachment

Orgin: ischial tuberosity
insertion: Posterior part of the medial tibial condyle

Function: Extend thigh and flex the leg also can medially rotate flexed leg

inn: Tibial division of sciatic N

Question 8

Semiomembranosus distal tendon divisions

Answer 8

distal tendon divides into two main parts:

Medial tibial condyle (muscle attachment)

Oblique popliteal ligament: reinforce the intercondylar portion of knee joint capsule, forms part of the popliteal fossa floor

Question 9

Biceps Femoris Muscle: Long head

Answer 9

Orgin: ischial tuberosity
insertion: Lateral aspect of the fibular head

Function: Extend thigh, flex leg, and laterally rotate flexed leg

Innervation: Tibial division of sciatic N

Question 10

Biceps femoris Muscle: short head

Answer 10

Orgin: lateral lip of linea aspera and lateral supracondylar line
Insertion: Lateral aspect of fibular head

Function: Flex leg and laterally rotate flexed leg

Innervation: Common fibular division of sciatic N

Question 11

Adductor Magnus muscle hamstring portion

Answer 11

Orgin: ischial tuberosity
Insertion: adductor tubercle on medial condyle

Function: Extend thigh

Innervation: Tibial division of sciatic N

Question 12

Hamstring Injury: Grade 1

Answer 12

muscle strain or tear
can involve avulsion fractures from the ischial tuberosity

Mild
Small disruption in structural integrity
minor swelling
no or minimal loss of strength

Question 13

Hamstring Injury: Grade 2

Answer 13

Muscle strain or tear
can involve avulsion fractures from the ischial tuberosity

Moderate
Partial tears with some intact muscle fibers
pain present
definite loss of strength

Question 14

Hamstring Injury: Grade 3

Answer 14

Severe
complete tear
swelling, severe pain and typically with accompanied hematoma
complete loss of motor function

Question 15

What supplies the posterior thigh muscles

Answer 15

the three perforating branches and terminal deep femoral arteries

also supplies Adductor magnus M

Question 16

Descending branch of lateral femoral circumflex artery

Answer 16

Descends anterior thigh

supplies the genicular anastomosis

Question 17

Descending Genicular Artery

Answer 17

arises from the femoral artery
branches out of the anteriomedial muscular septum with the saphenous N

supplies the genicular anastomosis

Question 18

What drains the posterior thigh?

Answer 18

Deep femoral Vein

Question 19

What innervates the skin of the posterior thigh

Answer 19

Posterior femoral cutaneous nerve

S1-S3

Question 20

Sciatic nerve rami components that innervate the muscles

Answer 20

even though tibial division of the sciatic nerve is L4-S3
and the Common fibular division of the sciatic nerve is L4-S2

the muscles of the posterior thigh recieve innervation from L5-S2

except Hamstring portion of adductor magnus which gets L4 of the tibial division of the sciatic Nerve

Question 21

Popliteal Fossa Boundaries: Superiorly

Answer 21

Superior medially: Semimembranosus and the semitendinosus

Superior laterally: Biceps femoris m

make up the superior angle of the fossa

Question 22

Popliteal Fossa Boundaries: Inferiorly

Answer 22

Inferiorly medially: Medial head of the gastrocnemius m

Inferiorly laterally: Lateral head of the gastrocnemius m

Question 23

Popliteal fossa boundaries: Floor

Answer 23

Popliteal surface of femur
Oblique popliteal ligament (from semimembranosus tendon)
Posterior surface of proximal tibia

Question 24

Popliteal Fosssa Contents

Answer 24

Superficial to deep:
Nerves
Popliteal vein, branches and lymph nodes
Popliteal artery and branches

Question 25

What does the popliteal artery terminate into

Answer 25

Anterior Tibial Artery Posterior tibial artery the popliteal artery also gives rise to the genicular branches

Question 26

Genicular Anastamosis

Answer 26

these bypass the popliteal artery supplies the articular capsule and ligaments of the knee joint ``` Superior lateral genicular artery Superior medial genicular artery Middle genicular artery (in joint capsule) Inferior Lateral genicular artery Inferior medial genicular artery ``` the inferior tend to be below the heads of the gastrocnemius heads

Question 27

Genicular anastamosis blood supply

Answer 27

Popliteal artery Descending branch of the lateral femoral circumflex artery Descending genicular artery from the saphenous branch and the articular branch

Question 28

Popliteal vein

Answer 28

formed by union of anterior and posterior tibial veins, usually near inferior border of popliteus muscle termination point of saphenous vein becomes femoral vein after traversing the adductor hiatus

Question 29

Where does the sciatic nerve usually end and what does it turn into

Answer 29

Sciatic nerve ends at the superior angle of the popliteal fossa turns into the Tibial Nerve and the common fibular nerve

Question 30

Tibial Nerve

Answer 30

larger component of the sciatic nerve descends centrally through popliteal fossa Innervates the posterior leg muscles, knee joints, skin on posterior leg as the medial sural cutaneous nerve

Question 31

Common fibular nerve

Answer 31

descends obliquely on lateral side of popliteal fossa medial to biceps femoris winds around the head and neck of the fibula and is susceptible to injury Innervates: anterior leg muscles via the deep fibular nerve Lateral leg muscles via the superficial fibular nerve skin on posterolateral leg via the lateral sural cutaneous nerve

Question 32

Sural Nerve

Answer 32

cutaneous nerve of posterior leg and lateral aspect of ankle and foot runs with small saphenous vein composed of medial sural cutaneous nerve from tibial nerve and sural communicating branch from the common fibular or lateral sureal cutaneous nerve

Question 33

Metaphyseal fractures

Answer 33

Distal femoral fracture transverse fracture accross the shaft most common distal femoral fracture occurs at metaphysis

Question 34

Physeal fractures

Answer 34

distal femoral fracture transverse fracture involving the epiphyseal plate commonly described by salter harris classification

Question 35

Posterior displacement of distal femoral fractures can lead to?

Answer 35

neurovasculature issues due to close proximity to femur in the popliteal fossa Vascular injury: Swelling in popliteal space, absent posterior tibial or dorsalis pedis pulses, slow distal capillary refill, cold pale feet Nerve injury: Motor injury with foot drop, sensory deficits to dorsal pr plantar foot

Question 36

Acute compartment syndrome

Answer 36

Increased pressure to a closed fascial compartment due to hemorrhage and or edema persistent deep ache or burning pain paresthesia pain with passive stretch muscle weakness

Question 37

Popliteal (Bakers) cysts

Answer 37

swelling of the popliteal fossa due to enlargement of the gastrocnemius semimembranosus bursa contain synovial fluid associated with degenerative and inflammatory joint disease mostly asymptomatic

Question 38

Peripheral Aneurysm

Answer 38

localized enlargement of an artery due to weakening of arterial wall Popliteal artery aneurysms is a common one may present with: claudication or ischemic pain at rest sensory/motor nerve deficit severe pain behind the knee

Question 39

Peripheral Artery disease

Answer 39

Atherosclerosis lack of blood flow leads to pain in affected muscle groups ``` may present with: Claudication Ischemic pain at rest severe diffuse pain nonhealing ulcer gangrene ```