Chapter 143 - nonatheromatous popliteal artery disease

Question 1

Popliteal artery entrapment syndrome first described

Answer 1

1879 Anderson Stuart (medical student) 1965 Love and Whelan coined the term

Question 2

Epidemiology of PAES

Answer 2

1) 80% men 2) median age 32 (20.7-41) 3) bilateral in 30% clinical, 67% anatomical

Question 3

Embroylogy of popliteal artery

Answer 3

1) umbilical artery –> axial and external iliac arteries 2) external iliac –> femoral artery in anterior compartment 3) axial artery in posterior compartment 4) 42d intrauterine: axial divide to 3 in relation to popliteus: proximal, deep, distal 5) proximal artery joins femoral via ramus communicans superius in adductor hiatus 6) proximal axial artery gives branch that joins distal axial artery 7) deep axial artery involutes

Question 4

Embryology of the medial head of gastrocnemius

Answer 4

1) Start from proximal tibia 2) migrate cranially end immediately caudal to adductor hiatus

Question 5

Heidelberg Classes of popliteal artery entrapment syndrome

Answer 5

TYPE 1: popliteal completes development before medial head migration –> pushes artery medially; normal gastroc location TYPE 2: popliteal artery maturation halts gastroc migration; abnormal insertion site on lateral side of medial condyle or intercondylar area TYPE 3: abnormal muscle slip or fibrous band from either of the femoral condyle traps the artery TYPE 4: persistence of axial artery thereby remain deep to popliteus muscle or fibrous bands TYPE 5: both artery and vein involved 10-15% TYPE 6: (functional, type F)

Question 6

Hypothesis for Type 6 popliteal entrapment

Answer 6

1) hypertrophy of gastroc 2) lateral attachment of medial head of gastroc

Question 7

Stages of popliteal entrapment syndrome in histology

Answer 7

STAGE 1: fibrosis to adventitia STAGE 2: fibrosis to media with dilatation and aneurysm STAGE 3: fibrosis into intima, thrombogenic

Question 8

Classification of popliteal entrapment symptoms

Answer 8

0 = asymptomatic 1 = pain, parethesia and cold feet after exercise 2 = claudication with walking > 100m 3 = claudication with walking < 100m 4 = rest pain 5 = necrosis

Question 9

Nerve and vein impingement in PAES

Answer 9

1) venous entrapment TYPE 5 can have calf cramp, compartment syndrome like and swelling 2) tibial nerve impingement can occur except in TYPE 6

Question 10

Manuevers that tense the gastroc muscle against entrapped artery

Answer 10

1) passive dorsiflexion 2) active plantar flexion

Question 11

Ishikawa sign

Answer 11

loss of pedal pulse with sharp knee flexion (adventitial cystic disease)

Question 12

Angiographic features in PAES

Answer 12

1) medial deviation of proximal popliteal artery 2) focal occlusion of mid popliteal artery 3) poststenotic dilation of the distal popliteal artery

Question 13

Management options for PAES

Answer 13

TABLE 143.3

Question 14

Surgical approach in PAES medial vs posterior

Answer 14

Medial: faster return to activity but only good for TYPE 1 and 2 Better exposure to distal popliteal Ease of GSV harvest Posterior: use of SSV

Question 15

Indications to repair popliteal artery in PAES

Answer 15

1) PSV >250 cm/s 2) velocity ratio >2 3) arterial occlusion 4) aneurysm degeneration

Question 16

Treatment of TYPE 6

Answer 16

1) monitor if asymptomatic 2) Botox –> paralyze slip of muscle responsible and aid muscle atrophy (controversial) 3) surgical decompression with muscle release 4) continue myectomy until intraoperative duplex show no further changes in velocity

Question 17

Patency after open bypass PAES

Answer 17

65-100% at 10 years interposition better than long bypass

Question 18

Adventitial cystic disease first described

Answer 18

1947 Atkin and Key (London) in EIA

Question 19

First adventitial cystic disease in popliteal

Answer 19

1954 Ejrup and Hiertonn (Sweden)

Question 20

% of ACD that are in popliteal artery

Answer 20

80.5%

Question 21

Laterality of ACD

Answer 21

mostly unilateral

Question 22

Epidemiology of ACD

Answer 22

1) male:female 5:1 2) mid 40’s

Question 23

5 theories of ACD

Answer 23

1) Repetitive trauma 2) Ganglion 3) Systemic disorder 4) developmental 5) articular/synovial

Question 24

Repetitive trauma theory key points

Answer 24

1) flexion and extension cause chronic injury and cystic degeneration 2) intramural hemorrhage 3) joint degeneration cause hydroxyproline secretion 4) hydroxyproline acts on intramural hemorrhage poor evidence athletes do not get it more

Question 25

Ganglion theory key points

Answer 25

1) ganglion and ACD have similar content of high hyaluronic acid 2) synovial cyst enlarge along arterial branch and implant itself poor evidence histology doesn’t match

Question 26

Systemic disorder theory key points

Answer 26

1) systemic mucinous or myxomatous degenerative condition causes ACD poor evidence bilateral disease rare

Question 27

Developmental theory key points

Answer 27

AKA cellular inclusion theory 1) mesenchymal mucin-secreting cells implanted in adventia during development 2) mesenchymal cells from joints incorporated into closely adjacent vessels

Question 28

Articular (synovial) theory key points

Answer 28

1) synovial fluid from joint egresses and dissects along adventitia of vessel branch to parent vessel

Question 29

Duplex finding of ACD

Answer 29

1) fine bright line that pulsates 2) no flow in cyst

Question 30

Angiography finding of ACD

Answer 30

1) Eccentric complression (Scimitar sign) 2) concentric compression (hourglass sign) 3) total arterial occlusion

Question 31

Nonresectional methods of ACD

Answer 31

1) Angioplasty - ineffective 2) cyst aspiration - high failure and high recurrence 3) cyst excision and evacuation

Question 32

Resectional method of ACD

Answer 32

Useful if extensive arterial degeneration or thrombosis

Question 33

Recurrence with different methods

Answer 33

Cyst aspiration 10-30% at 15 months Cyst evacuation 15% Cyst resection 6-10% Endo failure 37.5%-50% bypass and recon - less likely