Arterial, venous & misc. anatomy

Question 1

Compartments of the leg

Answer 1

The leg is divided into four osseofascial compartments by;
* Interosseous membrane of the leg
* transverse intermuscular septum
* anterior intermuscular septum

Anterior compartment
muscular
* tibialis anterior
* extensor hallucis longus
* extensor digitorum longus
* peroneus tertius
neurovascular
* deep peroneal nerve
* anterior tibial vessels

Lateral compartment
muscular
* peroneus longus
* peroneus brevis
neurovascular
* superficial peroneal nerve

Superficial posterior compartment
muscular
* gastrocnemius
* plantaris
* soleus
neurovascular
* tibial nerve

Deep posterior compartment
muscular
* tibialis posterior
* flexor hallucis longus
* flexor digitorum longus
* popliteus
neurovascular
* tibial nerve
* posterior tibial vessels

Question 2

Principles of vascular surgery

Answer 2

• End effects: ischaemia and/or haemorrhage
• Permissive hypotension
• Diagnosis
• Surgery
  o Exposure
  o Proximal and distal control
  o Exploration of vessel injury
  o Assess inflow/outflow
  o Repair
  o Bail out options
  o Adjuncts (angioembolisation and stents)
  o Protect the repair and the end organs

Question 3

Defintion of claudication

Answer 3

Reproducible pain in a muscle group on exertion that is relieved by rest

Question 4

Critical limb ischaemia

definition and classifications

Answer 4

Critical limb ischaemia:
* Chronic ischaemic rest pain (>14 weeks)
* Tissue ulceration or gangrene
* Attributable to arterial occlusive disease

Question 5

ABI and toe pressures

Answer 5

ABI
1.0 normal
<0.9 PVD
<0.5 critical limb ischaemia
An absolute toe pressure >30 mmHg is favorable for wound healing, toe pressures >45 to 55 mmHg may be required for healing in patients with diabetes

Question 6

Describe the femoral artery (course, branches, relationships)

Answer 6

• Commences at entry to thigh behind inguinal ligament, at the midpoint of the inguinal ligament, (halfway between the ASIS and pubic tubercle)
• Course: anteromedial part of the thigh in the femoral triangle then adductor canal
• Distal extent: adductor hiatus of adductor magnus -> becomes popliteal artery (near junction of middle and distal thirds of the thigh)
• Branches
  4 non-muscular branches and 2 muscular branches
• non-muscular branches
  superficial epigastric
  1cm below inguinal ligament; runs anterior to ligament up to umbilicus
  superficial circumflex iliac
  1cm below inguinal ligament, runs laterally to ASIS
  superficial external pudendal and deep external pudendal
  arise and pass medially, often under long saphenous vein, to supply skin of perineum and genitalia, anastomosing with internal pudendal branches
• muscular branches
  profunda femoris
  arises posterolaterally, gives lateral and medial circumflex femoral arteries soon after origin, then spirals behind femoral artery and vein to pass downwards to lie behind adductor longus
  descending genicular artery*

Question 7

Describe femoral triangle

Answer 7

A subfascial space which acts as a conduit for neurovascular structures entering and leaving the anterior thigh

Superior border: inguinal ligament
Medial border: medial aspect of adductor longus
Lateral border: medial aspect of satorius
Floor: longus, brevis, pectineus, psoas, iliacus (lets buy PPI)
Roof: fascia lata

Contents:
* Femoral nerve
* Femoral artery
* Femoral vein
* Lymphatics

The femoral artery & vein are wrapped in the femoral sheath composed from the transversalis fascia (anteriorly) and iliacus fascia (posteriorly), the nerve is outside the sheath

Question 8

Describe the adductor canal

Answer 8

Gutter shaped canal from femoral triangle to popliteal fossa
Boundaries

Entry: apex of the femoral triangle
Exit: adductor hiatus (between hamstring and adductor parts of adductor magnus) – structures passing through here pass into the popliteal fossa

Roof: fascia overlaid by sartorius
* Contained in fascia is subsartorial plexus
* Fed by branches from intermediate cutaneous nerve of thigh, saphenous nerve and anterior division of obturator nerve
* Supplies overlying fascia and skin
Walls/floor (gutter shaped groove):
* Vastus medialis laterally
* Adductors medially – longus above, magnus below

Contents:
Femoral vein (spirals around artery from lateral at adductor hiatus, posterior to medial at femoral triangle apex)
Femoral artery
Saphenous nerve (spirals from medial at hiatus, anterior to artery to lie lateral)
Branch of femoral nerve
Nerve to vastus medialis in upper part

Question 9

Hard and soft signs of arterial injury

Answer 9

Hard
* Pulsatile bleeding
* Expanding haematoma
* Absent distal pulses
* Cold, pale limb
* Palpable thrill or audible bruit

Soft
* Peripheral nerve deficit
* History of haemorrhage atthe scene
* Reduced but palpable pulse
* An injury in proximity of an artery