Musculoskeletal Flashcards
(141 cards)
1
Q
What is the benefit of doing an x-ray early on in osteomyelitis?
A
Rules out fracture and malignancy
1
Q
Which cells produce osteoid?
A
Osteoblasts
1
Q
What stimulates PTH release?
A
Low Ca2+
1
Q
Which bone cells does PTH act on directly to increase calcium?
A
Osteoblasts
1
Q
What are the 3 organs that PTH acts on to increase calcium levels?
A
Bone, kidney and GIT
1
Q
What type of collagen is in hyaline cartilage?
A
Type 2
1
Q
Where are the 3 places that elastic cartilage is present?
A
Ear, epiglottis and thyroid cartilage
1
Q
What are osteocalcin and alkaline phosphatase both markers of?
A
Osteoblast activity
1
Q
What are the little tubes that provide nutrients to osteocytes?
A
Canaliculae
1
Q
What is a displaced fracture?
A
Edges of fracture are not apposed
1
Q
What causes a stress fracture?
A
Repeated low force injury to a normal bone
1
Q
What are the 4 stages of fracture healing?
A
Inflammatory Reparative - Soft callus Reparative - Hard callus Remodelling
1
Q
What are the 2 major processes during the remodelling phase of fracture healing?
A
Osteoblasts and osteoclasts repopulate the bone Woven bone is remodelled to give lamellar bone
1
Q
Over what time frame does the hard callus phase of fracture healing occur?
A
Weeks to months
1
Q
Over what time frame does the remodelling phase of fracture healing occur?
A
Months to years
1
Q
What kind of fracture is most susceptible to infection?
A
Compound fracture
1
Q
What is the definition of osteoporosis?
A
Bone mass >2.5 SDs below the mean for healthy young women
1
Q
What is the definition of osteopaenia?
A
Bone mass 1-2.5 SDs below the mean for healthy young women
1
Q
What is the main concern with long term bisphosphonate treatment?
A
Oesophageal cancer
1
Q
What are the 2 main risks of long term oestrogen therapy for bone health?
A
Cardiovascular disease and breast cancer
1
Q
Is sarcopenia inevitable?
A
Yes
2
Q
What effect does VitD have in the gut?
A
Increases absorption of Ca and PO4 (phosphate)
4
Q
What are the 2 major processes during the hard callus phase of fracture healing?
A
Osteoblasts synthesise osteoid Osteoid becomes mineralised
5
Q
What class of hormone is VitD?
A
Steroid
5
At what age does muscle mass start to deteriorate?
50 years old
6
What is the most common form of calcium phosphate in bone?
Hydroxyapatite
8
What is the difference between the actions of PTH and VitD3 in the distal nephron?
PTH causes phosphate excretion, whereas VitD3 promotes phosphate reabsorption
9
What word means progressive loss of skeletal muscle mass with aging?
Sarcopenia
10
What is the motor uni?
An alpha motor neurone and all muscle fibres it supplies
11
Which protein is abnormal in Becker muscular dystrophy?
Dystrophin
13
What are osteocalcin and osteonectin?
Calcium binding proteins in the ECM of bone
15
Which bone cells produce collagen for cartilage?
Chondrocytes
16
What is the second common pathogen in osteomyelitis?
Strep pyogenes / Group A strep
16
Which pathogen is more common for osteomyelitis after a sneaker penetration injury?
Pseudomonas aeruginosa
17
What protein is a marker of muscle damage?
Creatine kinase
19
What causes progressive stiffening of muscle fibres with age?
Loss of elastin
21
Which gene can be knocked out in mice to cause massive muscles?
Myostatin
22
Define sarcopenia
Progressive loss of skeletal muscle mass and strength or performance with aging
23
In which 2 structures is fibrocartilage found?
Menisci and intervertebral discs
23
What percentage of muscle mass must be lost before there is the risk of mortality?
40%
24
How does denosumab treat osteoporosis?
It is a human monoclonal antibody that binds RANKL and iblocks RANK activity =\> reduces osteoclast activity
25
What type of collagen is in fibrocartilage?
Type 1
25
What is a compound fracture?
Open fracture, ie bone exposed to external world
25
What are the 2 major processes during the inflammatory phase of fracture healing?
Haematoma and granulation tissue
26
What are the 2 layers of the periosteum?
Inner cellular layer with osteoprogenitor cells Outer fibrous layer
27
Which bone cells are multinucleate?
Osteoclasts
29
In what direction do osteoclasts dig their holes in bone?
Along the stress axis of the bone
30
What are osteons aka?
Haversian systems
31
What is at the end of a bone? (-physis)
Epiphysis
32
What are the main types of muscle atrophy?
Disuse atrophy
Denervation atrophy
Cachexia
33
What is a comminuted fracture?
Fracture with more than 2 bits of bone
34
What percentage of cases of osteomyelitis occur in children \<5 years old?
50%
35
Over what time frame does the soft callus phase of fracture healing occur?
Days to weeks
37
What is osteomyelitis better known as?
Bone infection
39
What is the proper way to say 'bone infection'?
Osteomyelitis
41
Which bones are most commonly involved in osteomyelitis?
Long bones: femur, tibia, humerus
43
What is a pathological fracture?
Fracture where underlying bone pathology has made it more vulnerable to fracture
45
How do tendons and ligaments attach to bone?
Sharpey's fibres
46
What is raloxifene?
Selective oestrogen receptor modulator
47
What are bisphosphonates used to treat?
Osteoporosis
48
In which 3 locations is red bone marrow found in adults?
Skull, scapula and pelvis
50
Which protein is abnormal in Duchenne muscular dystrophy?
Dystrophin
51
What is the scaffolding for bone that is laid down by osteoblasts?
Osteoid
52
What do we call infection of a joint?
Septic arthritis
53
What percentage of the body's calcium is in bone?
99%
53
What effect does oestrogen have on bone?
Maintains bone density by promoting osteoclast apoptosis and increasing life span of osteoblasts and osteocytes
55
Which cells resorb bone?
Osteoclasts
56
How is most calcium lost from the body?
Urine
58
What is the main complication with a compound fracture?
Infection
60
Which cells are osteoblasts modified from?
Fibroblasts
61
What is a greenstick fracture?
Only one side of cortical bone is broken
62
How do bisphosphonates work?
They are an analogue of pyrophosphate thus taken up into bone matrix Taken up by osteoclasts, causing apoptosis
63
What do osteoclasts secrete?
HCl and proteases
65
What effect does PTH have on [Ca2+] in plasma?
Increases it
67
How long do most lower limb fractures take to heal?
12-16 weeks
68
What can be done to attenuate sarcopenia?
Strength training
68
Decreases in which 3 hormones are thought to be related to sarcopenia?
Growth hormone, IGF-1 and testosterone
69
What do osteoblasts turn into when they are less active?
Osteocytes
70
What is the name of the process by which long bones grow in length?
Endochondral ossification
72
What effect does PTH have on plasma [phosphate]?
Decreases
74
What is another name for cortical bone?
Compact bone
76
Which cells build bone?
Osteoblasts
78
Which two conditions are especially common in travellers to Asia?
Dengue fever and typhoid fever
79
Which cells are responsible for ongoing maintenance of cartilage?
Chondrocytes
80
What is calcitriol?
VitD3
81
How long do most upper limb fractures take to heal?
6-8 weeks
82
What is a complete fracture?
A bone is broken all the way through
84
What is the most common pathogen in osteomyelitis?
Staph aureus
85
How does PTH increase VitD levels?
PTH activates the kidney enzyme to hydroxylate/activate VitD3
87
What are 4 synonyms for the inner bit of a bone?
Medullary; cancellous; trabecular; spongy
89
Which NSAID should not be given for gout?
Aspirin
90
What does PTH cause osteoblasts to do?
Release OPG and RANK ligand to activate osteoclasts
91
What is Gower's sign?
Muscle weakness causes difficulty getting of floor, so Pt uses accessory muscles such as arms to help themselves get up
92
What is a sarcolemma?
Cell membrane of skeletal muscle
94
Where do osteoprogenitor cells usually reside?
Periosteum or endosteum
95
What type of muscle is more susceptible to sarcopenia?
Fast fatiguable
96
What is the goal of management of a fracture?
Unite the ends of the fractured bone
97
Over what time frame does the inflammatory phase of fracture healing occur?
Days
98
What is the antibiotic of choice for osteomyelitis?
Flucloxacillin
99
What are the 2 major processes during the soft callus phase of fracture healing?
Progenitor cells turn into chondrocytes Chondrocytes form cartilage
100
What is the role of dystrohpin?
It i links actin in the cytoskeleton to laminin via glycoproteins
101
What is at the middle of a bone? (-physis)
Diaphysis
102
What type of cell is in hyaline cartilage?
Chondrocyte
103
Name 4 things found inside a Haversian canal
Capillary, nerve, supportive connective tissue and lymphatic
104
For joint pathology, what will be the consequence of fibrillation and sloughing of articular cartilage?
Loss of joint space
105
For joint pathology, what will be the consequence of calcification of periarticular cartilage and synovium?
Osteophytes
106
For joint pathology, what will be the consequence of synovial fluid entering bone?
Subchondral cysts
107
For joint pathology, what will be the consequence of thickening of subchondral bone and trabeculae?
Subchondral sclerosis
108
What are the 4 main components of hyaline cartilage?
Type 2 collagen
Glycoaminoglycans
Chondrocytes
Water
109
What type of blood vessels are present in hyaline cartilage?
None
110
What type of nerves are present in hyaline cartilage?
None
111
How is hyaline cartilage nurished?
Perfusion by compression and decompression of the cartilage
112
What is added to plasma filtrate in the formation of synovial fluid?
Hyaluronic acid
113
What are the two types of cell in synovium?
Type A cells (macrophage-like)
Type B cells (fibroblast-like)
114
Give a 4 word definition of the pathophysiology of osteoarthritis
Chronic degeneration of cartilage
115
Which disease is characterized by degeneration of cartilage that results in structural and functional failure of synovial joints?
Osteoarthritis
116
How would you explain osteoarthritis to a lay person in 5 words?
Wear and tear of joints
117
At what time of day is pain from osteoarthritis worse?
At the end of the day
118
Pain at the end of the day suggests what type of arthritis?
Osteoarthritis
119
Which joints tend to be most affected by osteoarthritis?
Weight-bearing joints
120
At what time of day does pain from rheumatoid arthritis tend to be worst?
In the morning
121
Morning stiffness of joints suggests what type of arthritis?
Rheumatoid arthritis
122
Which disease is characterised by autoimmune inflammatory joint disease with systemic involvement?
Rheumatoid arthritis
123
What is podagra?
Gout in the great toe
124
What do we call gout in the big toe?
Podagra
125
Define gout
Very painful
acute inflammation
due to accumulation of uric acid crystals
in a joint
126
In which part of bone would you find osteons?
Cortical bone
127
What are 3 signs of osteoarthritis?
Reduced ROM
Crepitus
Osteophytes
128
What are 3 microscopic pathological features of rheumatoid arthritis?
Mononuclear infiltrate
Synovial hyerplasia forming pannus
Germinal centres
129
List 3 signs of rheumatoid arthritis
Inflamed joints
Rheumatoid nodules
Destruction and deformity of joints
130
Which joints of the hand are often spared in rheumatoid arthritis?
Distal interphalangeal joint
131
What diagnosis should you consider when someone presents with swollen joints, nodules and deformed joints?
Rheumatoid arthritis
132
What is the prevalence of rheumatoid arthritis?
1% of the population
133
List 3 x-ray features of rheumatoid arthritis
Juxta-articular osteopaenia
Subchondral erosions
Uniform joint space loss
134
What percentage of rheumatoid arthritis is genetic?
50%
135
List 3 risk factors for rheumatoid arthritis
Female gender
Age 25-55
Smoking
136
Accumulation of what causes gout?
Uric acid crystals
137
What are tophi?
Uric acid crystal depositions in soft tissues other than joints
138
What is the cardinal sign of gout?
Acutely inflamed, intensely painful joint
139
What type of inflammation is caused by tophi?
Granulomatous inflammation
140
What is the gold standard diagnostic test for gout?
Joint or tophus aspiration during an acute attack
