MSK Session 11 Flashcards
1
Q
What do all of the superficial posterior leg muscles attach to distally?
A
Calcaneal tendon
2
Q
What innervates the muscles in the posterior compartment of the leg?
A
Tibial nerve
3
Q
What common function do all muscles in the superficial layer of the posterior compartment of the leg share?
A
Plantarflex ankle
4
Q
What functions does gastrocnemius have in addition to plantarflexion of the ankle?
A
Raises heel while walking
Flexes knee
5
Q
What function additional to plantarflexion of the ankle does soleus have?
A
Steadies leg on foot
6
Q
Which muscles are in the deep layer of the posterior leg compartment?
A
Popliteus
Flexor hallucis longus
Flexor digitorum longus
Tibialis posterior
7
Q
What is the main action of popliteus?
A
Weakly flex knee
Unlock knee by rotating femur
Medially rotate unplanted limb
8
Q
What is the main action of flexor hallucis longus?
A
Flex all great toe joints
Weak plantarflexion
Support medial longitudinal arch of foot
9
Q
What is the main action of flexor digitorum longus?
A
Flex lateral 4 digits
Plantarflexion
Support longitudinal arches of foot
10
Q
What is the main action of tibialis posterior?
A
Plantarflex ankle
Invert foot
11
Q
From which nerve does the tibial nerve originate?
A
Sciatic
12
Q
Where can the tibial nerve be located at the ankle?
A
B/w tendons of FHL and FDL
13
Q
How does the tibial nerve enter the posterior compartment of the leg?
A
Passes b/w heads of gastrocnemius
14
Q
What happens to the tibial nerve at the ankle?
A
Divides into medial and lateral plantar nerves
15
Q
What is the sensory distribution of the tibial nerve?
A
Knee joint
Lateral and posterior part of inferior 1/3 of leg
Lateral foot and heel
16
Q
Which branch of the popliteal artery supplies the posterior leg and foot?
A
Posterior tibial
17
Q
What accompanies the posterior tibial artery in the leg?
A
Tibial nerve and veins
18
Q
Describe the path of the posterior tibial artery as it moves through the posterior compartment of the leg.
A
Posterior to medial malleolus
Runs b/w tendons of FHL and FDL
Divides into medial and lateral plantar arteries deep to flexor retinaculum
19
Q
What is the largest tibial artery branch called?
A
Fibular artery
20
Q
Describe the passage of the fibular artery in the posterior compartment of the leg.
A
Inferior to popliteus and tendinous soleus arch
Moves medially w/in FHL
21
Q
What does the fibular artery give rise to?
A
Nutrient artery of fibula
22
Q
What have their origin from the anterior and posterior tibial arteries?
A
Cx fibular artery
Nutrient artery of tibia
23
Q
What branches off from the anterior and posterior tibial arteries and anastomoses around the knee?
A
Cx fibular artery
24
Q
Which is the largest nutrient artery of the body?
A
Tibial
25
How are the veins of the posterior leg usually arranged?
As venae comitantes
26
What is present in all veins of the posterior leg to prevent back flow of blood?
Valves
27
What do veins in the posterior leg accompany?
All major arteries (so have same names)
28
Describe the veins through which blood in the posterior compartment of the leg drains.
Superficial --> perforating --> deep
29
How does calf muscle contraction aid venous return?
Propels blood to heart
| Closes lower valve therefore preventing bloodflow away from heart
30
How is the passage of the great saphenous vein described?
Medial
31
How is the passage of the small saphenous vein described?
Lateral
32
Which muscles make up the superficial layer of the posterior compartment of the leg?
Plantaris
Gastrocnemius
Soleus
33
What is the WHO definition of old age?
> 65 y.o.
34
Why will 40% of all women >50 y.o. have a fracture?
Osteoporosis
35
At what rate does bone mineral content decline after the age of 30?
~1% per year
36
What accelerates bone mineral loss?
```
Decreased reproductive hormone levels
Poor calcium
Poor vitamin D
Inactivity
Endocrine/GI pathologies
```
37
What causes a decrease in bone strength as both a material and a structure?
Loss of bone mineral
| Changes in architectural structure
38
What is sarcopenia?
Decrease in muscle mass due to loss of muscle fibres and decreased muscle cross sectional area
39
What happens with muscle contractility with age?
Decreases
40
Which neuron fibres are most affected by loss of neuronal innervation?
Alpha-motor (type II fast twitch)
41
Does the fact that men have a greater muscle mass in proportion to fat than women alter the rate of muscle loss b/w genders?
Nope
42
How can ageing exacerbate injury to the rotator cuff muscles?
Muscles become marbled w/fat --> tear --> cannot repair due to fat content
43
What four factors can increase fall risk and combined with bone weakness lead to fracture?
Decreased mobility
MSK-related posture and gait changes
Neuro-related gait and proprioception changes
Environmental hazards
44
What is type 1 osteoporosis caused by?
Post menopausal loss of oestrogen
45
What is type 2 osteoporosis caused by?
Old age
Hyperparathyroidism
Hypocalcaemia
46
What are the risk factors for osteoporosis?
```
Age
Decreased bone mass
Caucasian/Asian
Previous fragility fracture
+ve FHx
Low BMI
Lifestyle
Early menopause
```
47
What is the WHO definition of osteoporosis?
Skeletal disease characterised by decreased bone mass per unit volume
Deterioration of bone micro architecture leading to increased bone fragility and susceptibility to trauma #
48
How do bisphosphonates prevent bone resorption?
Taken up by osteoclasts
Inhibits mevalonate pathway
Osteoclast loses ruffled border so cannot sit on bone lining
Undergoes apoptosis
49
What effects do bisphosphonates have on bone turnover, mineralisation and bone volume?
Decreased turnover
Increased mineralisation
Minimal effect on volume
50
Give some examples of types of bisphosphonates.
Alendronate
Pamidronate
Zoledronate
51
What do bisphosphonates to do fragility fracture risk?
Decrease by 50%
52
What is the most important source of blood to the femoral head?
Medial circumflex artery
53
What will happen to 1 in 3 hip # patients?
Drop one level in mobility
54
How is an intracapsular hip # fixed?
Hemi/total arthroplasty
55
How is an extracapsular hip # fixed?
Dynamic hip screw
| Intramedullary rod
56
What is the NICE definition of osteoarthritis?
Disorder of synovial joints w/focal areas of damage to the articular cartilage, remodelling of underlying bone, formation of osteophytes and mild synovitis
57
What percentage of cartilage loss prevents bone from healing in osteoarthritis?
90%
58
How does osteoarthritis appear histiologically?
Loss of smoothness
Fibrillation and crevices present
Loss of cartilage means greater proportion of view is subchondral bone
59
What are the four radiological features associated with osteoarthritis?
Decreased joint space
Sclerosis
Osteophytes
Bone cysts
60
Where are bone cysts more commonly seen?
Shoulder
61
How can osteoarthritis be treated?
```
Weight loss
Physiotherapy (improves proprioception)
Analgesia
Joint injection
Arthroscopy
Osteotomies
Arthrodesis
Arthroplasty
```
62
What is an osteotomy?
Procedure to cut bone to offset loading which has manifested as bowing of the legs
63
What is arthrodesis?
Artificial joint ossification
64
Give some examples of complications associated with osteoarthritis treatments.
```
Leg length inequality
Dislocation
Loosening
Neurovascular damage
Infection
DVT (rare but treated prophylactically)
```
65
What is the problem with using a metal on metal hip replacement?
Release of metal ions into blood causing large losses of soft tissue
66
Give some examples of the type of joints that can be used for hip replacement.
Metal on polythene (mainly)
Ceramic
Highly X-linked polyethylene
Metal on metal
67
Describe the passage of the arteries of the lower limb.
External iliac --> femoral artery (-> deep artery of thigh -> medial and lateral circumflex femoral) --> popliteal artery --> anterior tibial, posterior tibial and fibular
68
Which arteries support the adductor muscles?
Deep artery of thigh
| Obturator artery from internal iliac
69
Where does the artery to head of femur arise from?
Obturator artery
70
Is the artery to head of femur important in the blood supply of the adult femoral head?
Nope
71
How can catheter access to the left side of the heart be achieved?
Femoral artery at mid-inguinal point
| Brachial/radial arteries
72
Where is the mid-inguinal point?
B/w ASIS and pubic tubercle
73
Why can catheter access to the right side of the heart not use veins in the arms?
Venae comitantes are too small
74
What venous access is used to access the right side of the heart with a catheter?
Neck
75
What is the contents of the adductor canal?
Saphenous nerve
Femoral artery
Femoral vein
76
What are the changes to the path of the femoral artery in the adductor canal?
Crosses to posterior aspect via adductor hiatus
77
Why is the popliteal artery not easily felt?
Deepest structure in the popliteal fossa
| Fascia surrounds fossa
78
What are the arteries of the posterior knee?
Superior, middle and inferior genicular arteries
79
Why are anastomoses needed in the anterior knee?
In full flexion the popliteal artery is obstructed so needed for sufficient blood supply
80
What position would you ask a patient to assume in order to palpate the popliteal pulse?
Prone with knee flexed to relax fascia
81
Why do you ask the patient to invert the foot when palpating the posterior tibial pulse posterior to the medial malleolus?
Relax flexor retinaculum
82
How does the anterior tibial artery enter the anterior compartment?
Pierces interosseous membrane
83
Where can the dorsalis pedis pulse be felt?
Just lateral to EHL tendon
84
Which artery is bigger, posterior tibial or anterior tibial?
Posterior
85
What are risk factors for formation of atherosclerotic plaque?
Uncontrolled DM
Hypertension
Dyslipidaemia
Smoking
86
What are the 8 stages of atheromatous plaque formation?
```
LDL through vascular endothelium
LDL oxidised
Cytokines released
Monocytes and macrophages migrate
Scavenger receptors activated
Smooth muscle migration
Foam cell formation
Cell apoptosis
```
87
In which part of the BV wall do atheromatous plaques develop?
Intima
88
Where are the 5 most common sites for atheromatous plaque formation, starting with the most common?
```
Abdominal aorta and iliac arteries
Proximal coronary arteries
Thoracic aorta, femoral and popliteal arteries
Internal carotid arteries
Vertebral basilar and middle cerebral
```
89
Why might you not be able to palpate a dorsalis pedis pulse in a patient?
Arterial occlusion in lower limb
| They are one of the ~2% of population with no dorsalis pedis pulse
90
What should an ankle brachial pressure index show if there is no arterial occlusion?
Similar blood pressures in arm and leg whilst lying down
91
What imaging methods can be used to assess arterial occlusion?
Doppler ultrasound
| Arteriogram
92
If the radius of an artery decreases by a half, how much will the flow reduce by?
1/16
93
What are the S/S of peripheral artery disease?
```
Lack of hair
Skin problems
Ulcers
Improper healing after injury
Infection
Loss of pulses
Cold
```
94
What are the Tx for peripheral artery disease?
Antiplatelets
Modify risk factors
Increase exercise to stimulate angiogenesis
95
What occurs in atherosclerosis to cause acute ischaemia?
Plaque rupture
96
How would a patient with a popliteal aneurysm present?
Oedema and pain in popliteal fossa with a palpable pulsatile mass
97
In which two lower leg injuries is the popliteal artery at risk of rupture?
```
# of distal femur
Dislocation of the knee
```
98
What is the superficial venous drainage of the lower limb?
Great and small saphenous veins
99
Describe the course of the great saphenous vein.
```
Arises from dorsal venous arch of foot
Courses anterior to medial malleolus
Passes about a hand's breadth medially of the patella
Through fascia lata at saphenous opening
Drains into femoral vein
```
100
What follows the great saphenous vein along its course?
Saphenous nerve
101
Describe the passage of the small saphenous vein.
Arises from lateral marginal vein of foot
Passes posterior to lateral malleolus
Course up posterior aspect of calf
Drains into popliteal vein in popliteal fossa
102
What is saphenous cut down?
Incision anterior to medial malleolus to gain access to great saphenous vein
103
When is saphenous cutdown used?
Emergencies e.g. hypovolaemic shock when veins have collapsed and venepuncture/cannulation is required
104
What is the pathogenesis of varicose veins?
Valve flaps become incompetent
Stasis of blood in veins
Dilated, tortuous superficial veins
105
What is the pathogenesis of venous insufficiency?
Valvular incompetence --> dull, aching, tingling legs combined with ulcers and slow healing wounds
106
What is postphlebitic syndrome a consequence of?
DVT
| Chronic deep venous insufficiency
107
What is the pathogenesis of postphlebitic syndrome?
Damage to venous valves --> lymphedema from high hydrostatic pressure in veins
108
What do deep veins of the lower limb follow?
Major arteries
