Nerves and blood supply of the lower limb Flashcards
1
Q
what does the aorta bifurcate into
A
- Aorta – bifurcates into the common iliac arteries at L4
2
Q
what does the common iliac artery divide into
A
- common iliac artery divides into internal and external iliac artery
3
Q
where does the internal lilac artery go
A
internal aspect of the pelvis
4
Q
where does the external iliac artery go
A
runs straight out of the bony pelvis and into the thigh
5
Q
what are the 3 branches of the internal iliac artery
A
- superior gluteal artery
- inferior gluteal artery
- obturator
6
Q
what does the piriformoris muscle do
A
- separates the superior gluteal artery and the inferior gluteal artery
- superior gluteal artery is above the piriformis
- inferior gluteal artery is below the piriformis
7
Q
where does the external iliac artery run
A
- External iliac artery runs into the anterior aspect of the thigh as the femoral artery
8
Q
where can you find the femoral artery
A
- midinguinal point
- - Halfway between ASIS and pubic symphysis
9
Q
what is the most common vascular injury
A
- Femoral vessels are the most common injured vascular structures being involved in nearly 70% of all arterial injuries
10
Q
what is the femoral artery useful for
A
- useful point of access to the aorta
- can be used in order to insert a stent into the artery
11
Q
where is the femoral artery found
A
femoral triangle
12
Q
what does the femoral artery give off when it is in the femoral triangle
A
- gives of the profunda femoris
13
Q
what does the profound femoris supply
A
supplies the posterior and medial compartments of the thigh
14
Q
what does the profound femoris give off
A
- Profunda femoris gives of the lateral and medial circumflex arteries that wrap around the neck of the femur
15
Q
what does the lateral and medial circumflex supply
A
- Lateral and medial circumflex arteries are important clinically as they give off branches that run up and supply both the neck and the head of the femur
16
Q
what does the obturator artery give off
A
- gives of a branch that goes to the head of the femur, it cannot supply the whole of the head of the femur therefore the lateral and medial circumflex arteries are important
17
Q
what can cause avascular necrosis in the femoral head
A
- if you damage the femoral neck then you can cut off the supply from the circumflex arteries and there more likely to have avascular necrosis of the femoral head
18
Q
where does the femoral artery run and when does it become the popliteal artery
A
- Runs in between the anterior and medial compartments of the thigh, superior to the knee joint it runs through the adductor hiatus and emerges posterior to the knee joint, it is known as the popliteal artery
19
Q
where does the popliteal artery run
A
- Runs through the popliteal fossa
20
Q
what does the popliteal artery divide into
A
- Branches into two main arteries the posterior (runs in the posterior compartment) and anterior tibial arteries (runs in the anterior compartment)
21
Q
where does the popliteal artery run
A
- runs in the posterior compartment of the leg and gives of a fibular branch laterally
22
Q
what does the fibular branch of the posterior tibial artery supply
A
lateral compartment of the leg
23
Q
describe where the posterior tibial runs
A
- runs posterior of the medial malleous
- goes through the tarsal tunnel which is behind the medial malloeous
- it then breaks up in the medial and lateral plantar arteries
24
Q
what does the posterior tibial artery break into
A
- it then breaks up in the medial and lateral plantar arteries
25
where does the anterior tibial artery run
- Branches from the popliteal artery and passes through the interosseous membrane to reach the anterior compartment, into the foot to become the dorsalis pedis artery
26
what does the dorsals pedis artery give off
arcuate arteries and then the tarsal branches
27
where can the dorsals pedis pulse be found
- Dorsalis pedis pulse can be found lateral to Extensor hallucis longus tendon
28
whereas does the small saphenous vein drain into
popliteal vein
29
where does the great saphenous vein drain into
femoral vein
30
what veins in the become varicose
great and short saphenous vein
31
describe what the superficial veins become varicose
standing and walking upright increases the pressure in the veins of your lower body
- Superifical veins are not in the deep fascia of the thigh therefore they are more unsupported than the deep veins
32
what are the muscles of the lower limb innervated by
- Muscles in the lower limb are all innervated by the lumbosacral plexus
33
the lumboscaral plexus is not...
entirely dedicated to the lower limb
34
describe the dermatomes
- L3 over the knee
- L5 big toe
- You stand of S1
- You lie of S3
- You sit of S3
- You wide S4
35
what are myotomes
- These are the motor equivalent of dermatomes – can test spinal levels in terms of motor action
36
what spinal segments do Flexion of the hip
- L2,3 lifts ones knee
37
what spinal segments do Extension of the knee
- L3,4 kick the door
38
what spinal segments do Dorsiflexion
- L4,5 Foot points to the sky
39
what is anterior movement
flexion of the hip
extentsion of the knee
dorsiflexion
40
what spinal segments do Extension of the thigh
- L4, 5 extend my thigh
41
what spinal segments do Flexion of the knee
- L5, S1 kick my bum
42
what spinal segments do Plantarflexion
- S1, 2 stand on my shoe
43
what are the divisors of the lumbrosacral plexus
- Lumbar plexus L1-L4
- Sacral plexus – S1-S4
- Lumbosacral trunk – L4-S4
44
what nerves originate from the lumbar plexus
- Femoral nerve
- Obtruatory nereve
- Lateral cutaneous nerve of the thigh
45
what is the spinal segments of lumbar plexus
- L2,3,4
46
what does the lumbar plexus innervate
- Innervate anterior compartment of the thigh
47
what are the causes of femoral nerve palsy
* Compression – from treatment for congenital hip dysplasia – acetabulum hasn’t fored straight away, treat – babys leg put in a cast that flexes the leg and extends the hip and puts the femoral head into the acetabulum
* Pelvic fractures
* Anterior hip dislocations (very very rare)
48
what are symptoms of femoral nerve palsy
- Paralysis of quadriceps (instability of the knee)
• Sensory loss anterior thigh and medial leg
• Rare to damage as it goes into the anterior comaprmetn and breaks up straight away
49
what are the spinal segments of the obturator nerve
L2-L4
50
where does the obtruator nerve go
- Runs around the medial aspect of the pelvis and passes through the obturator foramen and ends up in the medial aspect of the thigh
51
what movements do the obturator nerve control
- Adduction and hip adduction
52
what muscles do the obturaotyr never innervate
- Adductor Magnus – has a whole in it where the femoral artery passes through to become the popliteal artery (not the medial part of the adductor magnus is innervated by the obturator nerve)
- Adductor Longus
- Adductor Brevis
- Gracilis
53
what are the spinal segments of the lateral cutaneous nerve of the thigh
L2-L3
54
what does the lateral cutaneous nerve of the thigh innervate
- Provide sensory innervation to the lateral patch of the thigh
55
what arises from the sacral plexus
- sciatic nerve - divides into the tibial and common personal nerve
- Superior gluteal nerves
- Inferior gluteal nerves
56
where does the sciatic nerve run
largest nerve in the body, emerges from the posterior aspect of the pelvis, runs in the gluteal region and runs in the posterior aspect of the thigh
57
what is the spinal segments of the sciatic nerve
L5,S1,S2
58
what does the sciatic nerve innervate
- Innervates the hamstrings
| - Knee flexion
59
what does the sciatic nerve break into
- Breaks up into the tibial nerve and common peroneal nerve
| - Does this before entering the popliteal fossa
60
what makes up the hamstring
- Semitendinosus
- Semimembranosus
- Biceps femoris (long head)
61
what is the innervates the posterior compartment of the leg
• Tibial nerve
62
what is the artery supply to the posterior compartment of the leg
• Posterior tibial artery
63
what muscle movement does the posterior compartment of the leg do
* Plantarflexion
| * Flexion of digits
64
what innervates the anterior compartment of the leg
- Deep peroneal nerve
65
what is the blood supply to the anterior compartment of the leg
- Anterior tibial artery
66
what is the muscle movement of the anterior compartment of the leg
- Dorsiflexion
| - Extneison of digits
67
what innervates the lateral compartment of the leg
- Superifical peronaeal nerve
68
what does the lateral compartment of the leg do in terms of movement
- Eversion
69
what is the blood supply of the lateral compartment of the leg
- Fibrular artery
70
describe what the posterior compartment is divided into
- Divided into sub compartments these are the deep and superficial compartments
- All of the posterior compartments are innervated by the tibial nerve
71
describe what is in the posterior superficial compartment
- all muscles in then compartment insert on the achilles/calcaneous tendon
- Most superficial muscle is the gastronomes – it has two differne muscle heads and insert together onto the achilles/calcaneous tendons and is therefore involved in plantarflexion of the ankle
• Deep to gastrocnemius – is the soleus ( insert onto achilles tendon) and plantaris
72
what is the difference between the posterior superficial compartment and the posterior deep compartment
```
superficial
- plantarflexon
deep
- plantar flexion
- flexion of the digits
```
73
where do muscles of the posterior superficial compartment go
• All muscles pass through the tarsal tunnel and run inot the sole of the foot
74
what makes up the muscles of the posterior superficial compartment
- tibialis posterior
- flexor digitorum longus(involved in flexion of the tarsals)
- flexor hallucis longus (runs to the big toe)
75
describe the tarsal tunnel
- 3 tendons from the posterior deep compartment
- Posterior tibia artery
- Tibial nerve – breaks up into medial and lateral plantar nerves
76
what is the cause of tibial nerve palsy
* Fracture of tibia
| * Compression in tarsal tunnel (ankle)
77
what are the symptoms of the tibial nerve palsy
```
Paralysis
• Plantar flexors
Sensory loss
• Back of leg
• Sole of foot
```
- Compression in tarsal tunnel only gets sole of foot sensory loss as the tibial nerve would have already innervated the other muscles and sensors
78
describe the divisions of the sciatic nerve
- sciatic nerve divides into tibial nerve and common peroneal nerve
- common perineal nerve divides into superficial peroneal nerve and deep peroneal nerve
79
what does the common perineal innervate
- anterior and lateral compartment
- superficial - lateral compartment sensory innervation to the dorsal of the foot
- Deep to the anterior comparment – only provides sensory innervation between the big toe and the 2nd toe
- Wraps around the head of the fibula and then splits into the superifical and deep peroneal nerves
80
what are the muscles in the lateral compartment of the leg
- Peroneus longus
| - Peroneus brevis
81
describe how the muscles run in the lateral compartment of the leg
- Both tendons run behind the lateral malleolus
- Longus inserts onto 1st metatarsal/medial cuniform
- Brevis inserts onto 5th metatarsal
82
what are the muscles In the anterior compartment of the leg
• Tibialisis anterior, extensor digitorum longus, extensor hallucis longus
83
what can cause damage of the common peroneal nerve
- Wraps around the neck of the fibula – this is neck of the bone therefore if you get a fracture to the neck of the fibula then there is damage to the common peroneal nerve
- sensory loss to the dorsum of the foot
84
what happens if you get sciatic nerve injury
• Posterior hip dislocations
o Foot drop
o Wasting of hamstrings, calf muscles and dorsiflexors
o Loss of Achilles reflex
85
what does gluteus Maximus do and what is it innervated by
- Hip extension and lateral rotation
| - Innervated by the inferior gluteal nerve
86
what does the gluteus medium and minimum do and what is it innervated by
- Hip abduction and stabilisation of the bony pelvis
| - They are both innervated by the superior gluteal nerve
87
describe hip drop
- When you are standing up the bony pelvis is supported on either side by the lower lib
- If you take a leg of the floor then the bony pelvis is only supported on one side therefore the pelvis drops towards the side that you take the leg of the floor but you don’t get hip drop as the gluteus medius and minimus contract and keep the pelvis in a straight line
- Damage to the gluteal nerve – get hip drop
- This is the postitive Trendelenburg test
