1
Q
Name 3 fibrous joints
A
Periodontal ligament
Cranial sutures
Interosseus membranes (between radius and ulna) and (tibia/fibula)
2
Q
Fibrous joints are packed tightly with ?
A
Collagen fibres
3
Q
The difference between primary and secondary cartilaginous joints?
A
Primary (synchondrosis) - hyaline cartilage
Secondary (symphysis) - hyaline and fibrocartilage
4
Q
What type of joint is the growth plate in long bones?
A
Primary Cartilaginous (synchondrosis) - hyaline cartilage
5
Q
What type of cartilage is found on the end of bones?
A
Articular cartilage (type of hyaline cartilage) - acts as a shock absorber
6
Q
The intervertebral disk is what type of joint?
A
Secondary cartilaginous (Symphysis)
Hyaline and fibrocartilage
7
Q
Which part of the synovial joint produces synovial fluid?
A
synovial membrane
8
Q
What type of cartilage is articular cartilage, found at the end of long bones?
A
hyaline
prevents bones rubbing against each other
shock absorption
9
Q
what type of joint is the wrist joint?
A
condylar (ellipsoid)
circumduction
10
Q
the meniscus of the knee is made of what type of cartilage?
A
strip of fibrocartilage
11
Q
Hyaline cartilage is the weakest type of cartilage
a. true
b. false
A
a. true
12
Q
Why are glycosaminoglycans (GAGs) important for joints
A
attract water to joint because they are highly polar
e.g. hyaluronic acid
13
Q
Hyaluronic acid is a glycosaminoglycan (GAG)
a. true
b. false
A
a. true
14
Q
What are proteoglycans?
A
protein attached to GAGs (glycosaminoglycans)
e.g. Aggrecan!!
15
Q
Chondroblasts near the articular surface of hyaline cartilage produce what glycoprotein?
A
Lubricin - lubricates joints
16
Q
What molecules is produced by chondrocytes (mature cells) in the transitional layer of hyaline (articular cartilage)?
A
Aggrecan - proteoglycan (protein + GAGs)
Attracts water
17
Q
what type of collagen predominates in cartilage
A
Collagen type 2
18
Q
what type of collagen predominates in bone?
A
Collagen type 1
19
Q
The collagen fibres in articular cartilage change orientation from superficial to deep layers
a. true
b. false
A
a. true
20
Q
Why does articular cartilage have a high water content 70-80%
A
Water is incompressible!!!!
bond with molecules like Aggrecan (proteoglycan) is high polar - attracts water, GAGS - hyaluronic acids (also polar)
Is produced by chondrocytes
21
Q
what produces synovial fluid at a synovial joint?
A
synovial membrane - synovium (tissue the membrane is made of)
cells - synoviocytes
22
Q
why is synovial fluid important?
A
supply cartilage with nutrients and remove waste products from PERIPHERY once diffusion process is over
23
Q
features of synovial membrane that make it efficient at delivering nutrients and removing waste products from cartilage?
A
- rich capillary network
- no epithelial lining
24
Q
Type B synoviocytes are the main producer of synovial fluid
a. true
b. false
A
a. True
are fibroblast like
25
Type A synoviocytes are the main producer of synovial fluid
a. true
b. false
b. false
mainly remove debris - macrophage like
do contribute to production of synovial fluid
26
Which type of synoviocytes are the main producer of synovial fluid?
Type B
27
What is the content of synovial fluid
Fluid component - comes from blood plasma
Hyaluronic acid (GAG molecule - polysaccharide which is polar)
Lubricin (glycoprotein)
28
which nerve supplies the majority of posterior arm and forearm compartment (Extensors)?
the radial nerve (C5-C8)
posterior cord
29
which nerve supplies the deltoid muscle
axillary nerve (C5, C6)
comes from posterior cord
30
what are the cords of the brachial are named according to what?
their position to the axillary artery (posterior, lateral , medial)
31
which nerve is at risk if there is a mid-humeral shaft fracture?
Radial nerve C5-C8
sits along posterior of the bone (radial groove)
- wrist drop - can't extend wrist
32
What nerve is at risk when the shoulder is dislocated?
Axillary nerve C5-C6
deltoid of shoulder
33
nerve responsible for supplying most of the extensors in the arm and forearm ?
Radial nerve C5-C8
wrist drop if damaged - can't extend wrist
34
Which nerves are derived from the posterior cord?
Axillary - C5/C6
Radial - C5-C8
35
musculocutaneous nerve supplies muscles in the anterior part of forearm
a. true
b. false
b. false
Anterior ARM!! - no branches below elbow
36
what nerve supplies the trapezius
spinal accessory nerve
37
what is the movement produced by the serratus anterior on the scapula?
protraction
holds scapula in!!! if damage long thoracic nerve - winged scapula
38
what nerve innervates the serratus anterior?
long thoracic nerve (branch of brachial plexus)
winged scapula results if damaged
39
winged scapula is due to damage to what nerve?
long thoracic nerve - innervates serratus anterior
(damaged during surgery in axilla)
40
the latissimus dorsi is attached to the scapula
a. true
b. false
b. false
humerus - intertubercular sulcus
41
actions of biceps
supination!!
flexion of ELBOW
flexion of SHOULDER
42
what nerve supplies the triceps
radial nerve C5-C8
(extensors in arm and forearm - posterior compartment)
43
actions of triceps
shoulder extensor
elbow extensor
44
what nerve supplies the brachioradialis?
radial nerve
(flexion of elbow) - muscle of forearm
flexor- supplies by radial nerve because it arises posteriorly
45
which bone moves in pronation of the forearm?
Radius doing movement!! around ulna
46
pronator muscles?
pronator terres
pronator quadratus
47
supinator muscles?
biceps brachii
brachioradialis
48
what joint does pronation/supination occur?
superior/inferior radio-ulnar joints!!!
NOT about wrist or ELBOW
49
the distal interphalangeal joints are usually spared in rheumatoid arthritis
a. true
b. false
a. true
PIPs and MCPs (metacarpophalangeal joints)
and wrist (radio-carpal)
50
primary site of infection in rheumatoid arthritis?
synovium
51
rheumatoid arthritis only effects the central joints
a. true
b. false
b. false
does not effect central joints - lumbar, scaro-iliac or distal interphalangeal joints
52
what disease is felty syndrome a characteristic of?
Rheumatoid arthritis
+ splenomegaly
+ reduced neutrophils/leukaemia
53
What is a key feature of x-rays in RA?
Bone erosions
54
what antibodies are associated with RA?
Anti-cyclic citrullinated antibodies - anti CCP- ACPA
Rheumatoid factor RF
55
what is the most common crystal in gout?
Monosodium urate
56
what is the end product of purine metabolism in humans?
URIC ACID (urine)
hypoxathaine -> xathine -> plasma urate -> uric acid
57
what type of collagen fibres are ligaments made of
type 1
58
enthesitis
inflammation were ligaments and tendons attach to bone
59
main purpose of ligaments
stability throughout R of M
different portions tensed at different positions
60
Ligament that prevents anterior displacement of knee
Anterior cruciate
61
What are the anterior and posterior ligaments of the knee called?
cruciate ligaments
62
what are the vertical lateral and medial ligaments of the knee called?
collaterals
63
what are the semi-circular ligaments placed horizontally on the knee called?
lateral and medial meniscus
64
what type of collagen are ligaments made out of
type 1
65
how are ligaments different from tendons
- join bone to bone
- less collagen
- less organisation of collagen
- more water and proteoglycans
- more compliant
- rounder fibroblasts
66
what part of the tendon does the epi-tenon cover?
the tendon
67
what part of the tendon does the fascicle level of tendon covered by
paratenon
68
what part of the tendon are the collagen bundles level covered by?
endo-tenon
69
outline structure of the tendon
Tendon - epitenon
Fascicles - paratenon
Collagen fibres - endotenon
70
what are the main cells of tendons called
tenocytes
71
why is immobility bad for tendons
reduces water content +
glycosaminoglycans (GAGs) concentration
and
strength
72
What is the main component of inorganic bone extracellular matrix (ECM)?
hydroxyapatite
73
What is the main component of organic bone extracellular matrix (ECM)?
Collagen type 1
74
What is the correct order of events in bone remodelling?
1. activation - of pre-osteoclasts
2. resorption - osteoclasts digest/resorpt
3. Reversal - osteogenic environment
4. Formation - rebuilding tissue
5. termination - apoptosis of osteoblasts
75
Osteogenesis imperfecta is a genetic disorder which affects the production of which biological substance?
Type 1 Collagen
genetic disorder - causing it to be of reduced strength or present in reduced amounts
76
composition of yellow bone marrow?
80% fat
15% water
5% protein
77
bone resorption increases with age
a. true
b. false
a. true
78
Where is red bone marrow found in adults?
only found in flat bones?
ribs, pelvis, sternum, vertebrae
X not in long bones X
79
Where is red bone found in children?
metaphysis and epiphysis of long bones
tibia, femur , humerus
80
What is avascular necrosis?
cellular death of bone components due to interruption of the blood supply, preventing adequate tissue perfusion
epiphysis of long bones at weight bearing joints - e.g. head of long femur
81
Where do osteoblasts originate from?
multi-potent mesenchymal stem cells (e.g. of adult stem cells)
also - differentiate into fibroblasts, adipocytes and myocytes
82
pregnancy raises the Vitamin D requirements, hence you are more likely to become deficient in vitamin D
a. true
b. false
a. true
83
Low body fat percentage is protective against osteomalacia
a. true
b. false
a. true
if you have a high BF% leads to a higher risk because increased fat stores create a higher capacity for vitamin D storage, hence less circulates in the bloodstream
84
Rickets is a skeletal disorder caused by lack of which of the following nutrients?
Vitamin D
unable to absorb calcium and phosphate from food
85
steroid therapy can increase the risk of avascular necrosis
a. true
b.false
a. true
- esp femoral head
86
Osteomalacia is a skeletal disorder caused by the lack of which of the following nutrients?
calcium
(children - rickets)
87
What is the definition of bone mineralisation?
Organic bone matrix becomes filled with calcium phosphate nanocrystals to enhance the development of bone
increased rigidity of bone
88
What happens to osteoblasts and osteoclasts in osteoporosis?
Imbalanced activity
Increased Osteoclast activity
Decreased Osteoblast activity
More bone resorbed than created - bone mineral density decreases
89
What is required in order for active transport of calcium to take place?
Calcitriol (active vitamin D)
synthesised in kidney
calcium binding protein
90
How does calcitriol (vitamin D) alter the absorption of calcium from the intestines?
increases the expression of calbindins, which are calcium binding proteins
allowing more calcium to be absorbed from the intestines
91
What is the correct definition of osteomalacia?
Osteopenia with disordered calcification
leading to a higher proportion of unmineralized tissue (after epiphyseal closure)
imbalance of minerals (calcium/phosphorous) - decreased ability of bones to harden
92
osteoporosis can result in vertebral crush fractures
a. true
b. false
a. true
can lead to a loss of height "dowagers hump"
93
Which cells do Haversian canals provide oxygen and nutrients to?
osteocytes
94
Which compound does the mineralised matrix of bone mainly consist of?
crystallised hydroxyapatite
95
what is pagets disease?
Paget's disease of the bone is a disease associated with brittle, abnormally shaped, weak bones.
This is due to increased bone formation and bone resorption, meaning that bone turnover is very dysregulated and uncontrolled.
96
Rheumatoid arthritis is an autoimmune disease affecting the synovial joint. Certain treatments can target cytokines involved in its pathogenesis.
Which of the following cytokines has the most important role in the pathogenesis of rheumatoid arthritis?
TNF-alpha
97
outlines the correct order of fracture healing?
1. inflammation
2. soft callus
3. hard callus
4. remodelling
progresses from haematoma to to lamellar bone formation
98
Which term describes bone first formed in development?
woven bone
99
vitamin C plays a critical role in bone formation, so a deficiency can increase the rate of bone loss
a. true
b. false
a. true
decrease in osteoid formation and bone mineralisation
100
A key property of cartilage is its high swelling pressure which allows cartilage to resist loads and not collapse when squashed.
Which feature of cartilage gives it this property?
proteoglycan aggregates
Proteoglycans consist of a protein core to which large chains of negatively charged glycosaminoglycans (GAGs) are attached. The negatively charged GAGs attract and bind water molecules, creating a highly hydrated gel-like structure within the cartilage matrix.
This high water content, maintained by the proteoglycan aggregates, gives cartilage its ability to resist compressive forces and provides its characteristic high swelling pressure. When compressed, water is squeezed out of the cartilage, but the proteoglycan aggregates resist the collapse of the matrix, maintaining its shape and integrity.
101
A key property of cartilage is its high swelling pressure which allows cartilage to resist loads and not collapse when squashed.
Which feature of cartilage gives it this property?
proteoglycan aggregates
Proteoglycans consist of a protein core to which large chains of negatively charged glycosaminoglycans (GAGs) are attached. The negatively charged GAGs attract and bind water molecules, creating a highly hydrated gel-like structure within the cartilage matrix.
This high water content, maintained by the proteoglycan aggregates, gives cartilage its ability to resist compressive forces and provides its characteristic high swelling pressure. When compressed, water is squeezed out of the cartilage, but the proteoglycan aggregates resist the collapse of the matrix, maintaining its shape and integrity.
102
what are proteoglycans?
protein core with large chains of negatively charge GAGs attached.
negative GAGs attract and bind water molecules
103
what type of collagen is affected in osteogenesis imperfecta?
type 1 collagen
brittle bones and frequent breaks
104
osteoblasts express large quantities of the alkaline phosphatase enzyme
a. true
b.false
a.true
critical for mineralisation - liberate inorganic phosphates
ALK- alkaline phosphate is a biomarker of bone turnover
105
Outline the 4 steps in regeneration of fractures
1. inflammation /haematoma
2. soft callous
3. hard callous
4. Remodelling
106
valgus
has moved laterally!!!! (L -> laterally)
- lower part of limb
107
varus
has moved medially - towards the midline
- lower part of the limb
108
simple fracture
bone is broken into 2 pieces
109
complex fracture
1. bone is comminated into > 3 piece
2. segmental
3. butterfly segment > 3 pieces
110
What is a transverse simple fracture?
the bone is broken into 2 pieces
straight across
usually due to direct trauma/straight blow with no twisting
111
what is an oblique simple fracture?
There is a slight bending force!!
Bone tends to shorten/ 2 pieces
112
what is a spiral simple fracture?
twisting - rotational force
angle < 20 degrees
LONG SURFACE AREA - 2-3 x width
HEALS quickly!!!!
113
How are fracture deformities described?
1.displacement (anterior/posterior/medial/lateral)
2. angulation (anterior/posterior/varus/valgus) to and from middle in degrees
3. rotation (internally or externally)
4. axial deformity (shortening , overlapping)
5. soft tissue - air/gas/fluids/foregin bodies
114
What is the blood supply to the hip?
Femoral artery -> profundus femoris -> lateral and medial circumflex femoral ->
Ascending branch of medial femoral circumflex*** is main contributor to femoral head
115
functions of the synovium?
maintains intact tissue surface
lubricate cartilage
controls synovial fluid volume and composition
nutrition of the chondrocytes
116
what cells are found in the lining of synovium
macrophages
fibroblasts
produces and maintains lubricans
117
what is found in the sublining of the synovium?
loose connective tissue
blood vessels
fibroblasts - make connective tissue
118
What is the ACPA response in Rheumatoid athritis
Citrullination (deamination) , conversion of amino acid Arginine -> Citrulline (AA)
altered of excessive citrullination -> formation of autoantibodies (and loss of self-tolerance)
119
what activates osteoclasts in RA ?
RANK ligand (cytokine) - is produced by synovium in RA
increased erosive damage
120
What cells do osteoclasts come from
myeloid progenitor cells
121
what cells do osteoblasts come from
mesenchymal progenitor cells
122
Osteoblasts produce RANK ligand
a. true
b. false
a. true
binds to receptors on osteoclasts and increases division of nuclei in osteoclasts - stimulate to eat up bone
123
what is the cause of osteogenesis imperfecta
defect of type 1 collagen
124
how do bisphosphonates work?
bind to bone mineral and prevent bone breakdown
125
What are Rheumatoid factor antibodies directed against?
Fc region of immunoglobulin G
126
A 67-year-old woman with a history of chronic hip pain underwent a total left hip replacement. One week postoperatively, she presents to her GP, reporting an abnormal gait.
During the examination, the GP observed that when the patient bears weight on her left leg, the right side of her pelvis drops.
What nerve is most likely to be affected in this case?
A patient is found to have a positive Trendelenburg sign - superior gluteal nerve
