Anatomy Limbs 8 - Review of Lower limb nerves and Vessels Flashcards
How many C,T,L,S,C vertebrae are there
7C 12T 5L 5S 1C
C1-4 innervates?
Neck
C5-T1 innervates?
Upper limb
T2-L1 innervates?
Trunk
L2-S3 innervates?
Lower limb
S2-C1 innervates?
Perineum
Which nerve supplies the anterior compartment of the thigh?
Femoral n
It passes under the inguinal ligament
Which nerve supplies the medial (/adductor) compartment of the thigh?
Obturator nerve
Passes through the obturator foramen
Which nerve supplies the posterior thigh, posterior & anterior foot and leg?
Sciatic nerve (which gives off tibial and common peroneal branches)
Why is piriformis an important muscle to remember?
Superior gluteal nerve passes above it and inferior gluteal nerve passes below it
Sciatic nerve and posterior cutaneous nerve of the thigh emerge inferiorly also
When does the tibial nerve split off?
Just before it enters the popliteal fossa
Where is the common peroneal nerve susceptible to damage?
Common peroneal nerve continues superiorly and It wraps around the head of the fibula - there
Tibial nerve supplies?
Posterior part of the leg
What does the tibial nerve divide into?
Medial and lateral plantar nerves
The common peroneal artery divides to give 2 branches, what are they and what do they supply?
Deep peroneal nerve - anterior muscles of the leg
Superficial peroneal nerve - lateral muscles of the leg
Where does the saphenous nerve come from and what does it do?
It branches off the femoral nerve and supplies part of the leg and the medial side of the foot
Which spinal nerves form femoral nerve
L234 (posterior fibres)
Aside from anterior thigh, what other muscle does femoral nerve supply?
Iliopsoas
Which spinal nerves form obturator nerve?
L234 (anterior fibres)
Which spinal nerves for sciatic nerve?
L345 S123 (ant. and post. fibres)
Which spinal nerves form the superior gluteal nerve?
L45S1
What muscles does the superior gluteal nerve supply?
Gluteus medius and minimus, tensor fascia lata
Which spinal nerves supply inferior gluteal nerve?
L5 S12
What muscle does the inferior gluteal nerve supply?
Gluteus maximus
Which spinal motor nerve roots are involved in:
flexion of the knee?
extension of the knee?
Flexion knee = L5/S1
Extension knee = L3/L4
Which spinal motor nerve roots are involved in: flexion of the hip?
extension of the hip?
Flexion hip = L2/L3
Extension hip = L4/L5
Which spinal motor nerve roots are involved in: plantar flexion (flexion of ankle)? dorsiflexion (extension of ankle)?
Plantarflexion: S1/S2
Dorsiflexion: L4/L5
From which roots doe the fibres of the posterior cutaneous nerve originate
S1/S2
Give some examples of autonomous sensory zones
S1 - lateral calf
L3 - mid thigh
L4 - Lower thigh
The dorsal lateral cutaneous nerve is a branch of??
The sural nerve
Give an example of root injury of L5/S1 prolapsed disc. What are the signs
Motor - loss of foot eversion
Sensory - loss of sensation on outer border of foot
Reflex - loss of ankle jerk
Lesion of common peroneal nerve at the fibular neck - what are the signs
(common peroneal nerve = anterior and lateral part of leg)
Motor - foot drop
Sensory - dorsal of foot at least
Explain how circumflex femoral artery arises
Aorta - Common iliac - ext and int - (ext) femoral - profunda femoris - circumflex
At the knee, how does the femoral artery split
Femoral artery - popliteal artery - TRIFURCATION INTO:
- Anterior tibial artery - becomes dorsalis pedis artery
- Posterior tibial artery
- Peroneal artery
After the femoral has given off the deep branch (profunda femoris), the femoral artery continues downwards via?
The adductor canal
The femoral artery goes from anterior to posterior via what structure?
Adductor Magnus hiatus
It then becomes the popliteal artery
What are the borders of the femoral triangle
Superiorly - Inguinal ligament
Medially - lateral border of adductor longus
Laterally - medial border of sartorius
What is present in the femoral triangle
Femoral Nerve, artery and vein
What forms the popliteal fossa
Diamond shape
Formed by borders of the semimembranosus, biceps femoris and heads of gastrocnemius
What does the popliteal fossa contain
Popliteal artery and vein
Tibial and common peroneal nerves (but common peroneal nerve leaves the fossa)
What drains into the popliteal vein?
Small saphenous vein
The posterior tibial artery passes behind?
The medial malleolus
Post. tibial forms a plantar arch in the foot by giving off medial and lateral plantar arteries
How does the superficial venous supply go?
Dorsal venous arch - Long saphenous & short saphenous - perforating veins - saphenofemoral junction (long saphenous)
Short saphenous arises more from which venous network
Plantar venous network
The deep veins run alongside the arteries, often as?
Venae comitantes (2/3 veins together)
Where and when would you do a long saphenous vein cut down?
At the medial malleolus (just superior and lateral to)
Done if patient is in shock
Now superseded by intraosseous administration
What are the deep veins progression
Anterior and posterior tibial veins - popliteal vein - profunda femoris vein -femoral vein (receives long saphenous vein) - external iliac vein
Intermittent claudication can be caused by?
Arterial embolism (often associated with arterial disease)
What is compartment syndrome
Ischaemia caused by trauma-induced increased pressure in confined limb compartment -
Commonly occurs in anterior, lateral and posterior compartments of the leg
What pressure is required to collapse small vessels in the leg?
Normal pressure = 25mmHg
Pressure of 50-60mmHg can collapse small vessels and cause compartment syndrome
(Pulse still present as it comes from large vessel with high BP)
What are the 2 types of compartment syndrome and what causes them?
Acute compartment syndrome - trauma associated
Chronic compartment syndrome - exercise induced
How is acute compartment syndrome treated to prevent muscle death in the affected compartment?
Emergency fasciotomy
What vein connects superficial veins to deep veins
Perforating veins
What causes varicose veins?
When the valves of the perforating veins are weak - causes blood to be pushed from deep veins back to superficial veins
What is the most important valve in terms of varicose veins?
Sapheno-femoral junction valve
THIS IS THE MAJOR CONNECTION
What can varicose veins cause?
Venous insufficiency (not enough venous return) and lipodermatosclerosis (skin thickening), venous ulcers
Where are DVT formed?
Clot in the deep veins - can cause PE and death
Can be prevented by contracting leg muscles
Which 2 veins can be used for CABG?
Long and short saphenous veins
