MSK System Flashcards
1
Q
List the 7 functions of the bone
A
Adapt to movement
Repairs itself
Structural support
Attachment sites for muscles
Reservoir for calcium & phosphorus
Defence against acidosis
Trap for dangerous minerals
2
Q
Briefly explain bone architecture- what it looks like
A
Cortical and compact with strong dense regular structure
3
Q
What forms a haversian system
A
Deposited bone replaced by lamellar bone
4
Q
What is bone made if
A
Collagen and minerals
5
Q
What specific cell are osteoblasts
A
Mesenchym stem cells
6
Q
Functions of osteoblast
A
Builders-
Hormone receptors
Secrete factors to activate osteoclast
Bone marrow secrete proteins
7
Q
When a osteoblast is trapped by new bone…
A
Forms osteocyte
8
Q
Main function of osteoCLast
A
Breakdown bone= CLearance
9
Q
Where are osteoclasts formed
A
Fusion of precursor cells forming a multinucleate synctium
10
Q
Finish the sentence…
Bone resorption is mediated by…
And needed for…
A
Mediated by osteoclasts
Needed by radial growth/ bone remodelling
11
Q
Define osteogenosis
A
Calcium phosphate crystal precipitate & attach to a collagenous lattice support
12
Q
Bone arises to….
A
Replacement of pre existing tissue
13
Q
Cartiliage is a …
A
Endochondral ossification
14
Q
Embryonic mesenchyme
A
Intramembraneous ossification
15
Q
Osteogenesis is needed for
A
Matrix formation & mineralisation
16
Q
Where does ossification start
A
Primary zone in middle of long bones & extends as waves of ossification
17
Q
Explain the process of endrochondral ossification
TELL A STORYY!
A
Cartilage model laid by chomdrocyte
Cartilage calcified forming scaffold for osteoblast
Osteoblast make mateix by secreting osteoid
Osteoblast secrete alkaline phosphate to calcify matrix
Wave of osteoclast removes calcified cartilage & make lacunae bone
18
Q
How does bone growth in length
A
By proliferation of chondrocytes at epiphyseal plate
19
Q
How does bone grow in diameter
A
Deposit new bone under periostal collar = simultaneous resorption
20
Q
What is bone marrow responsible for
A
Haematopoeisis
21
Q
In the bone, what allows passage of mature blood cells into circulation
A
Narrow seive like elements
22
Q
2 classification of stem cells
A
Haemo
Mesenchymal
23
Q
What is calcium needed for
A
Muscle comtraction
Nt release
Resting membrane potential signal transduction
Blood coagulation
Bone
24
Q
What is phosphorus needed for
A
Signal transduction at po4
Atp
Creatinine
Bone
25
What are calcium and phosphorus controlled by
Pth
Vitamin d
26
Where does phosphate regulation take place
Kidney
27
Increased PTh results in
Decreased po4 in blood
28
Effect of vitamin d
Inhibits PTH production
+ vit d = - PTH = + po4 in blood
Exception is renal tubular disease
29
Effect of hypocalcaemia on skeleton
Calcium leaves skeleton = affect strength
30
Plasma calcium regulation controlled by
Vitamin d
Pth
31
Compare how pt & vitamin d control blood calcium levels
Pth - 3 mechanisms fast- increase bone resorption & distal tubing reabsorption & renal vit d synthesis
Vit d - dihydroxyvitamin d - 2 mechanisms = + bone resorption & + intestinal ca absorption
32
In plasma calcium regulation, vitamin d ….
Inhibits PTH transcription
33
MOA of PTH
Bind & activate Pth receptors but doesnt not express them
34
Difference between bone resorption & formation
Resorption- prolonged pth activation
Formation - intermittent pth activation
35
List actions of vit d
More ca absorbed in si
Stimulate protein transcription
Open ca channels
Stimulate osteoclast make as PTH BUT stop pth synthesis
36
What is osteomalacia & rickets
Osteo-
Defective mineralisation of bone matrix when remodelling
Rickets- defective mineralisation of epiphyseal cartilage in growing skeleton
37
Primary PTH is caused by
HYPERcalcaemia
38
Symptoms of hyperparathyroidism
Stone kidney
Bones - tumour
Moans - deprrssion
Groans - gi irregula
39
Causes and symptoms of secondary hyperparathyroidism
increased PTH in response to hypocalcaemia
===
Chronic renal failure due to filtration of phospaht
Decreased activation of vit d
Decreased ca absorption
40
Figures of bone densities according to NICE
Normal less than 1
Osteopenia 1-2.5
Osteoporosis- more than 2.5
41
Risk factors for osteoporosis
AGEING
age
Gender
Ethnicity
Famikial
Smoking
42
Bone arcitechture under microscope
30 yr old - thick interconnected plates of bone
71 - fragile rods
43
Moa of nsaids
Stop cycloxygenase that produce AA metabolites
44
Effect of prostaglandin
Sensitive nerve endings= cause pain
45
What are eicasanoids
Inflamm mediators,grouped prostaglandins/ thrmoboanxe-leukotrines
46
Pgi2
Prostacyclin
Vasodilate
Hyperalgesic
Stop platelet aggregation
47
Pge2
Vasodilator/ hyperalgesic
48
All vasodilators synergise with
Histamine 7 bradykinin WHICh
Reducing pain but sensitise afferent C fibres
Dont increase vascular permeability but potentiate effects of histamine & bradykinin
49
Cox 2 pathway is
Inducible induce prostaglandin pathway = pain
50
Cox 1 pathway
Consituitive - induce prostaglandin
Protect gut mucosa
Haemostasis
Vasodilator
Promote ulcer healing
51
side effects of NSaids
Gi disturbances
Stop platelet aggregation
Stop mediated renal function
Stop uterine motility= longer gestational
Hypersensitivity reactions
52
Group of med for paracetamol
Analgesic & antipyretic with no anti inflammation properties
Inhibits cns prostaglandin make
53
Se for para
Kidney damage with prolonged use
Over dose hepatotoxicity = glutathione induction
54
Types of analogues for morphine
Synthetic or morphine with same moa
55
Difference between opium/ opioids/ opiate
Opium from papaver somniferum, morphine& alkaloids
Opioids - substance wuth synthetic/ natural liker effect
Opiate syntheticmorphine
56
Whats a narcotic
Morphine / codein analgesic action in cns
57
Endogenous opiods
All gpcr negatively linked to adenylate cyclase = cellular inhibition
58
Where can opiods act
More than one receptor can be agonist for one and antagonist for second and partial for third
59
Opioid analgesic effects
Effective in acute/ chronic pain
Tumour growth
Tissue inflammation
Reduce affective component pain
60
Opioid effect on brain stem
Terminate descending fibres in dorsal horn
Inhibit primary afferent firing
Stimulate intrinsic internuerons
61
Opioids can cause…
Resp depression in therapeutic doses however no CV depression
62
Moa for codeine and treatment
Low affinity for opioids receptors
Mild to moderate pain relied
Cough supression
Control of diarhea
Can be combined with paracetamol and aspirin
63
Se of codiene
Nausea vomiting
Sedation disziness
Constipation
64
Differnece between codeine and dihydrocodein
Di- low efficacy & same potency 2 codeine / metabolised to active compound
65
Why do 10% of population have no therapeutic effect to codeine
Lack metabolising enzyme converting to morphine
66
3 theories for pain
Periphery to spinal cord = primary fibres- dorsal horn neurones
Spinal gate theory of pain- not at afferent synapse
Ascending patways & brain
67
Definition of pain
Unpleasant sensory & emotional experience associated with actual pr potential tissue damage
68
Pain is a combination of
Sensory (discriminative)
&
Affective
(Emotional) components
69
Definition of nociception
Sensory of pain alone
Activity starts in nociceptor
70
Pain can be a mixture of
Nociceptice & non noci
71
Define nociceptive pain
Stimulation of specific pain receptors @ dista end of sensory neurones heat/stretch
72
Define non noci pain
Peripheral & cns , generated by nerve cell dysfunction
73
Pain classed a disease with
Being 20% of population
In females more
Some wanting to die
74
Differenct between acute and chronic pain
Acute- predictable/ tissue damage/ circuitry known/ unimodal treatment/ responds predictably
Chronic- opposite & difficult to treat persist longer than 12 weeks or beyond tissue healing time
75
Define somatic pain with characteristic
Tissue muscle joint pain
Nocireceptors / inflammation
Sharp localised pain
Useful meds para weak opioids
76
Visceral pain
Internal organs of main body cavities
Thorax abdomen
Nocireceptors
Deep vague ache
Weak strong opioid
77
2 types of nociceptors
Mechanical- strong sharp pain- d fibres
Polymodal- dull burning - c fibres
78
Sharp pain has a
Dull pain has a
Low threshold fast transmission
High threshold & slow transmission
79
AB fibres in spinal gate theory are
Mechanoreceptors
80
Ad receptors at gate theory are
Mechano
Noci
81
C receptors in gate theorh are
Noci
Thermo
Mechanical
82
In the ascending pathway and brain theory, describe pathway
To lambic system- spinothalamuc oathway
Percieved @ subcortical
Localises @ cortical level
83
What closes the spinal gate
Release of 5 ht nkradrenaline enkephalin
84
Pain can chnage plasticity leading to
Increased sensitivity to pain
85
Increased sensitivity to pain
Hyperalgesia
86
Allodynia
Responding with pain when there is no pain
87
Persistent pain is a
Physiological process allowing healing
88
The MSK is
Connection of bones & muscle fibres via connective tissue and tendons
89
Functions of msk
Locomotion
Maintenance if posture
Respiration
Communication
Constriction of organ vessels
Heart beat
Production of body heat
90
Properties of muscles
Contract - shorten /pulling force
Excitability- respond to stimuli
Extensibility- stretched back to original
Elasticity- recoil to original length
91
Classification of gross anatomy
Skeletal
Smooth
Cardiac
92
Skeletal
Locomotion
Pressure
Resp movements
Voluntary in action
Controlled by somatic motor neurones
93
Smooth
Walls of hollow organs
Bv/ iris
Mix food in gi
Dilate contrict pupils
Not striated & mononucleated
94
Cardiax
Heart
Source if movement of blood
Autorhymic striated & mononulceated
95
Movement of muscke
Skeletal
Origin
Insertion
Indirect
Direct
96
Skeletal movements
Movement by tension between ends
97
Origin movement
Proximal attachment muscle attaches to least moveable area
98
Insertion
Distal movement muscle attaches to muscle moves most
99
Indirect attachment
Epimysium extends beyond muscle as tendon to periosteum of bone
100
Direct attachment
Epimysium adheres/ fuses to periosteum
101
Skeletal muscle organisation
Muscle
Fasicle
Muscle fibre
Myofibril
Myofilament
102
A muscle cell eith a cell membrane is a
Sarcolemma
103
Epimysium tissue
Dense regular surrounding entire muscle
104
Perimysium
Collagen & elasctic fibres called fasicle
105
Endomysium
Loose connective tissue surrounding individual muscle fibres
106
Aponeurosis
Collagen fibres of all 3 layers = flattened tendon like structures
107
Muscle fibres vary depending on
Atp pathway
Myoglobin content
Sustained ot short work
Atp decomposition
Slow/ fast twitch
108
Slow twitch - fatigue resistant musckes are:
Slow oxidative/ slow actin atpase enzyme
Slow mysoin & contractility
High myoglobin
Strong prolonged contraction
109
Examples of slow twitch
Postural= spinal extensor
Antigravity = calf muscle
110
Fast twitch fatigue muscles are
Everything fast eg fast oxidative/ atpase / contractility
Plenty glycogen
High intensity contractions
Extensive sarcoplasmic reticulum = rapid release & storage of ca ions
111
3 types of joints and differences
Fibrous
Cartilage
Synovial
Different degrees of mobility
112
Fibrous joint
Cannot move
connective tissue eg fontanelles
113
Cartilaginous joint
Entirely cartilage little movement
2 types synchondroses & symphyses
Fibrocartilagepubic, verterbrae
114
Synovial joint
Joint with space between adjoining bones
Synovial cavity filled with fluid
Synovial fluid = greater movements
115
Weakest joint
Synovial
116
Why is a synovial joint covered with hyaline cartilage
Prevent excessive pressure to allow joint to move easily
117
Describe meniscus
Cartilage on bothe ends never come into contact
Separated by thin film joint fluid & 2 shock absorbers
118
List the synovial joints
Gliding
Ball & socket
Hinge joint
Saddle joint
Pivit
Condyloid
119
Description of gliding joint
Bones meet flat bones move along in any direction, very flexible
Carpals
Metacarpals
120
Description of ball & socket
Highest freedom of motion
Shoulder & hip
For support
121
Description of hinge joint
Elbow
Flexion & tension
Joint capsule= strength & lubrication resistance to mecahnical stress
122
Description of saddle joint
Saddle & horse
Stability & flexibilty
Thumb
123
Pivot joint
Cervical vertebrae
124
Condyloid joint
Egg shaped ball & socket
125
Cartilage is
Strong avascular chondroitin collagen
Can be hyalin
Elastic & fibrocartilage
126
Tendon is A
Fibrous connective tissue attach kuscle to structure eg eyeball
127
Ligament is a
Finrous elastic attachment from bone to bone made of fibrocyted
128
2 types if ligaments
White rich collagenous sturdy & elastix
Yellow elastic rush
129
What does intracellular fluid between myofibrils contain
Large quantities of K/ mg2 / phosphate/ protein enzymes / mitochondria/ ATP
130
Myofibrils are
Repeated sarcomere light & dark bands depending on how light passes
131
Myosin & actin attach to which bands
Actin- light I band
Myosin - dark A band
132
I & A bands are polarises by
I band isotropic to polarised light
A band anisotropic to polarised light
133
What is a sarcomere
Actin and myosin, repeating unit of 2Z desks end of acting attached to zdisk and myosin M band
134
What is the function of the Sarco plasmic reticulum?
Regulates calcium storage, release uptake and is important to muscle contraction
135
Describe the process of muscle contraction
Miles in cross bridges attached to the actin, filament working/the mile Stillhead pivots, and then is it pours on the actin filament, sliding it towards the m line
As the new ATP attaches to the myosin head, the Crossbridge detaches is ATP is split into ADP and pie cooking of the myosin head occurs
136
What is a motor unit?
Single motor neurone
137
How is the skeletal muscle excited?
By large myelinated, nerve fibres originating from motoneurons in anterior hands of spinal cord
138
In the neuromuscular junction, how does synaptic signalling occur?
Action potential is initiated in both directions towards the muscle fibre ends releasing a CH
139
What is a transverse tubule and how does action potential take place?
Skeletal muscle fibres action potential spreads along the surface membrane, and the maximum muscle contraction requires deep penetration of muscle fibre. The transverse tubules allow transmission of action potential throughout the muscle.
140
The role of ACH receptors
Na influx and depolarisation
141
The role of na in AP
Greater depolarisation
142
The role of calcium in action potential
Calcium influx
143
The role of calcium, 2+ an action potential
 Changes tropomyosin, enabling active sites
144
What is a myasthenia gravis?
Autoimmune disease, which targets and destroys AC hate receptors
