Case 14 Flashcards
(358 cards)
1
Q
Distinguishing features of cervical vertebrae
A
Bifid spinous process
Transverse foramina
Triangular vertebral foramen
2
Q
Transverse foramina conduct the…
A
Vertebral arteries
3
Q
How is C7 different from other cervical vertebrae?
A
Longer spinous processes
Spinous process is not bifid
4
Q
Inferior demifacet of thoracic vertebra articulates with…
A
Head of rib inferior to it
5
Q
Superior demifacet of thoracic vertebra articulates with…
A
Head of its respective rib
6
Q
Costal facets of thoracic vertebrae articulate with…
A
Tubercle of their respective rib
7
Q
Distinguishing features of thoracic vertebrae
A
Demifacets on superior and inferior lateral surface of vertebral body
Costal facets on transverse processes
Long spinous process slanted inferiorly
Circular foramen
8
Q
How many cervical vertebrae are there?
A
7
9
Q
How many thoracic vertebrae are there?
A
12
10
Q
How many lumbar vertebrae are there?
A
5
11
Q
Distinguishing features of lumbar vertebrae
A
Very large
Kidney shaped body
Triangular foramen
12
Q
How many sacral vertebrae are there?
A
4
13
Q
How many bones make up the coccyx?
A
5
14
Q
Coccyx articulates with…
A
Apex of sacrum
15
Q
How many articulations does each vertebrae have?
A
5
16
Q
Vertebral articular surfaces are covered with…
A
Hyaline Cartilage
17
Q
Cartilage which makes up the intervertebral disc
A
Fibrocartilage
18
Q
Anterior Longitudinal Ligament is (Thick/Thin) and prevents (Hyperextension/flexion)
A
Thick
Hyperextension
19
Q
Posterior Longitudinal Ligament is (Thick/Thin) and prevents (Hyperextension/flexion)
A
Thin (weaker)
Hyperflexion
20
Q
Ligamentum Flavum connects
A
Lamina to Lamina
Located on inner surface of vertebral foramen
21
Q
Interspinous ligaments connect…
A
Spinous processes, attaching between ligaments
22
Q
Supraspinous ligaments connect…
A
Spinous processes, attaching to the tips
23
Q
Intertransverse ligaments connect…
A
Transverse processes
24
Q
Facet joints in the spine are strengthened by…
A
Ligamentum flavum
Interspinous ligaments
Supraspinous ligaments
Interspinous ligaments
25
Primary curvatures of the spine
Those that develop in utero
26
Secondary curvatures of the spine
Those that develop when the baby holds its head upright and begins to walk
27
Atlas
C1
28
Axis
C2
29
Nuchal ligament extends from.... to....
Occipital protuberance
Spinous process of C7
30
Function of nuchal ligament
Limits flexion of the head
31
Vertebral notch
Notch below the pedicle.
Forms the intervertebral foramina .
Where spinal nerve roots and ganglia exit the vertebral canal.
32
Annulus Fibrosus
Outer, fibrous part of IV disc.
Fibres insert into epiphyseal rim.
Contains blood vessels.
Thickens with age.
33
Nucleus Pulposus
Central core of IV disc.
85% water at birth, dehydrates, losing proteoglycans and elastin with age.
Avascular - receives blood from vessels in AF.
34
Action of Trapezius
Upper fibres: Elevate and rotate scapula
Middle fibres: Retract scapula
Lower fibres: Pull scapula inferiorly
35
Motor innervation of trapezius
Spinal Accessory Nerve (CNXI)
36
Action of Latissimus Dorsi
Extends, adducts and medially rotates the upper limb
37
Innervation of Latissimus dorsi
Thoracodorsal nerve
38
Action of levator scapulae
Elevates scapular
39
Innervation of levator scapulae
Dorsal Scapular Nerve
40
Origin and Attachment of Trapezius
Skull, nuchal ligament, spinous processes C7-T12
to
Clavicle, Acromion and scapula spine
41
Origin and attachment of Latissimus Dorsi
Spinous processes of T6-T12, Iliac crest, thoracolumnar fascia, inferior 3 ribs
to
Intertubular sulcus of humerus
42
Origin and attachment of Levator Scapulae
Transverse processes of C1-C4
to
Medial border of scapula
43
Action of Rhomboids
Retracts and rotates scapula.
| Keeps scapula compressed against thoracic wall
44
Innervation of Rhomboids
Dorsal Scapular Nerve
45
Origin and attachment of rhomboid minor
Spinous processes C7-T1
to
medial border of scapula (superior to r.major)
46
Origin and attachment of rhomboid major
Spinous processes T2-T5
to
Medial border of scapula (inferior to r.minor)
47
Action of Serratus Posterior Superior
Elevates ribs 2-5
Involved in respiratory function
48
Action of Serratus Posterior Inferior
Depresses ribs 9-12
Involved in respiratory function
49
Innervation of Serratus Posterior muscles
Intercostal nerves
50
Origin and attachment of Serratus Posterior Superior
Nuchal ligament, spinous processes C7-T3
to
Ribs 2-5
51
Origin and attachment of Serratus Posterior Inferior
Spinous processes T11-L3
to
Ribs 9-12
52
Superficial, extrinsic muscles of the back
Trapezius
Latissimus Dorsi
Rhomboids
Levator scapulae
53
Intermediate, extrinsic back muscles
Serratus posterior superior and inferior
54
Superficial, intrinsic back muscles
Splenius Capitis
| Splenius Cervicis
55
Action of splenius muscles
Rotates head to the same side
56
Bilateral contraction of splenius muscles
Head and neck extension
57
Origin and attachment of splenius capitis
Nuchal ligament and spinous processes C-T3
to
Mastoid process
Occipital bone of the skull
58
Origin and attachment of splenius cervicis
Spinous processes T3-T6
to
Transverse processes C1-C3/4
59
Intermediate, intrinsic back muscles (lateral to medial)
Iliocostalis
Longissimus
Spinalis
(I long for spinach)
60
Action of iliocostalis
Unilateral - lateral flexion
Bilateral - extension
61
Action of longissimus
Unilateral - lateral flexion
Bilateral - extension
62
Action of spinalis
Unilateral - lateral flexion
Bilateral - extension
63
Innervation of erector spinae
Posterior rami of spinal nerves
64
Origin and attachment of Iliocostalis
Common tendinous origin
(Travels superiorly)
to
Costal angle of ribs
Cervical transverse processes
65
Origin and attachment of longissimus
Common tendinous origin
(Travels superiorly)
to
Lower ribs
Transverse processes C2-T12
Mastoid process of skull
66
Origin and insertion of spinalis
Common tendinous origin
(Travels superiorly)
to
Spinous processes of C1 and T1-T8
Occipital bone
67
Deep, intrinsic back muscles
```
Semispinalis
Multifidus
Rotatores
Interspinales
Intertransversari
Levatores costarum
```
68
Innervation of intrinsic back muscles
Posterior rami of spinal nerves
69
Action of semispinalis
Extension and contralateral rotation of head and vertebral column
70
Origin and attachment of semispinalis
Transverse processes C4-T10
to
Spinous processes C2-T4
Occipital bone
71
Action of multifidus
Stabilises vertebral column
72
Origin and attachment of multifidus
Sacrum, P. Iliac spine, Common tendinous origin
Mamillary processes of lumbar vertebrae
Transverse processes of T1-T3
Articular processes C4-C7
to
Spinous processes of vertebrae 2-4 segments above
73
Action of rotatores
Stabilises vertebral column
| Proprioception
74
Origin and attachment of rotatores
Transverse processes
to
Spinous processes of immediately superior vertebrae
Lamina
75
Attachments of interspinales muscles
Span between adjacent spinous processes
76
Attachments of Intertransversari muscles
Span between adjacent transverse processes
77
Attachments of Levatores Costarum
Transverse processes C7-T11
to
Rib immediately below
78
Action oof levatores costarum
Elevates ribs
79
Ostoclasts
Breakdown bone for reabsorption
| Release of calcium
80
Osteoblasts
Form bone
| Found in periosteum in Howship's Lacuna
81
Osteocytes
Initiate remodelling
| Connected to other osteocytes by long projections (Form gap junctions)
82
Osteophytes
Bony projections that form during bone degeneration
83
Effect of oestrogen and testosterone on bone
Increased apoptosis of chondrocytes
| Leads to ossification of growth plate by osteoblasts
84
Secreted by chondrocytes to allow bone mineralisation/calcification
Alkaline Phosphatase
85
Primary centre of ossification
Middle of diaphysis
86
Secondary centre of ossification
Epiphysis
87
Epiphyseal plate
Cartilage between primary and secondary centres
AKA Growth plates
88
Effect of vitamin D on plasma Calcium
Increases Ca2+
| Activates osteoclasts
89
Effect of PTH on plasma calcium
Increases Ca2+
| Activates osteoclasts
90
Effect of calcitonin on plasma calcium
Decreases Ca2+
Activates osteoblasts
Inhibits osteoclasts
91
Basic unit of compact bone
Haversian System/Osteon
92
Lacunae are connected by...
Canaliculi
93
Lacunae contain...
Osteocytes
94
Canaliculi contain...
Projections from osteocytes
95
Haversian Canals conduct...
Blood vessels and nerves from periosteum
96
Lamellae
Concentric rings surrounding Haversian Canal
97
Structure of cancellous/trabecular/spongy bone
No osteons
| Has trabeculae surrounding bone marrow containing spaces.
98
Spinal cord is a continuation of...
Medulla oblongata
99
Cauda Equina
Bundle of spinal nerves and nerve roots
| Consists of 2-5th lumbar nerve pairs
100
Spinal cord terminates at...
L1/2
101
Filum terminale
Continuation of pia mater from conus medullaris
Connects to coccyx
102
Conus medullaris
Occurs at L1-2
Tapered end of spinal cord
Branches out to form cauda equina
103
Anterior spinal artery arises from.... via...
vertebral artery
Foramen magnum
104
Anterior spinal artery supplies...
Whole cord
| Anterior to posterior grey columns, bilaterally
105
Posterior spinal arteries arise from... via...
Posterior inferior cerebellar arteries
Foramen magnum
106
Posterior spinal arteries supply...
Their own side of grey and white posterior columns
107
Radicular feeder arteries enter spinal column via...
Intervertebral foramina
108
Arteria Radicularis Magna/Artery of Adamkiewicz
Large radicular artery
| Found at T10/11
109
A-delta fibres are responsible for...
Immediate, sharp pain
Response to mechanical stimulation, cold and pressure
110
C fibres are responsible for...
Slow, dull pain (Visceral)
Response to high temperatures and chemical stimuli
111
Effect of substance P
Stimulates histamine release from mast cells
| Causes vasodilation and inflammatory response
112
Mechanism for referred pain
Visceral and cutaneous afferents converge on a single dorsal horn.
Pain from an organ can be felt at the same level that the dorsal horn cutaneously innervates
113
Primary hyperalgesia means being
More sensitive to pain when tissue is damaged
114
Secondary hyperalgesia refers to a
Long-term potentiation of pain signals
115
Allodynia
Pain due to a stimulus that isn't normally painful
116
Mechanism for primary hyperalgesia
Inflammation or damage causing release of Histamine/5-HT/Sub P
Decreases threshold of firing in silent neurons.
Afferents that are normally silent become sensitised and produce action potentials
117
Mechanism for secondary hyperalgesia
Build up of substance P in dorsal horn
NMDA receptor becomes more sensitive to glutamate.
Pain occurs in undamaged tissues
118
Endogenous opioids
Endorphins and enkephalins
119
Where is periaqueductal gray located?
Midbrain
120
Effect of stimulation of Periaqueductal gray
Analgesia
121
Anterior ramus of spinal root supplies...
Muscles and skin in anterolateral body and limbs
122
Posterior ramus of spinal root supplies
Muscles and skin of back
123
Two parts of Dorsal Column
Cuneate and Gracile Fasciculi
124
Function of Dorsal Column
Fine Touch
Vibration
Proprioception
125
Cuneate Fasciculus carries...
Information on fine touch/vibration/proprioception from upper limb
126
Gracile Fasciculus carries...
Information on fine touch/vibration/proprioception from lower limb
127
Where do fibres from the dorsal column cross over?
Medulla
128
Once fibres from Dorsal column have crossed over, they are known as...
Medial Leminiscus
129
Dorsal Column synapses in...
Thalamus
130
How does pain/temperature information reach the brain?
Spinothalamic tract
Enters spinal cord, ascends 1-2 levels in Lissauer's Fasciculus
Synapses in substantia gelatinosa in Dorsal Horn.
Crosses over in AWC.
Ascends in ST tract up to thalamus.
131
Function of lateral corticospinal tract
Motor control of limbs
132
Function of ventral corticospinal tract
Axial motor control (central)
133
Post central gyrus
Sensory
134
Precentral gyrus
Motor
135
Decussation of the pyramid is...
Where corticospinal fibres (to the limb) cross over in the medulla
136
Motor information to the limbs is transported in fibres which cross over in...
The medulla
137
Motor information to the axial muscles is transported in fibres which cross over in...
The anterior white commissure
138
Where do neurons from motor cortex synapse?
Anterior Horn
139
Dermatome
An area of skin that is supplied by a single spinal nerve
140
Thumb dermatome
C6
141
Middle finger dermatome
C7
142
Little Finger dermatome
C8
143
Nipple dermatome
T4
144
Umbilicus dermatome
T10
145
Glans penis dermatome
S3
146
Knee dermatome
L4
147
Little toe dermatome
S4
148
Myotome responsible for ankle reflex
S1-2
149
Myotome responsible for knee reflex
L3-4
150
Myotome responsible for biceps reflex
C5-6
151
Myotomes responsible for triceps reflex
C7-8
152
Herniated disc is normally caused by..
Age related degeneration of annulus fibrosis.
| Allows nucleus pulposus to bulge out into vertebral canal.
153
Diagnosis of herniated disc
T2 MRI - visualising soft tissue
CT is not useful
154
Treatment of herniated disc
NSAIDs +/- nerve blocks/epidurals
Surgery if severe
155
Risk factors for mechanical back pain
Older
Female
Chronic pain elsewhere
Psychosocial factors
156
Presentation of mechanical back pain
Stiffness
Scoliosis on standing
Muscle spasm and tenderness
Relief with sitting/standing/rest
157
Treatment for mechanical back pain
Analgesia
Physiotherapy
Avoidance of excessive rest (to prevent chronic LBP)
Muscle relaxants may be used
158
Facet Syndrome
Narrowing/osteopathic changes in facet joints causing back pain.
Usually cervical
159
Spondylosis
Degenerative Osteoarthritis of joints causing narrowing
160
Pathophysiology of Spinal and Root Canal Stenosis
Loss of disc height
Osteophyte formation
OA of joints
161
Presentation of Spinal and Root Canal Stenosis
Pain (brought on by walking, relieved by rest)
Parasthesia - in distribution of affected nerve
Bending forward may provide relief (opens canal)
162
Spondylolisthesis
Forward displacement of vertebra
Causing low back pain
Extreme case of spondylolysis (fracture of pars interarticularis)
163
Vertebrae in which spondylolisthesis most commonly occurs in
L5
164
Treatment of spondylolisthesis
Surgical realignment of vertebra
165
Age group commonly affected by spondylolisthesis
Young people (<20)
166
Diffuse Idiopathic Skeletal Hyperstosis
Bony growths and ossification of ligaments
167
Presentation of Diffuse Idiopathic Skeletal Hyperstosis
Stiffness of the spine (not always painful)
More commonly in patients with metabolic syndrome.
168
Treatment of Diffuse Idiopathic Skeletal Hyperstosis
NSAIDs
169
Presentation of facet joint damage
Pain to myotome region of affected spinal nerve.
| Pain worse on bending backwards and on straightening
170
Ankylosing Spondylitis mainly affects which groups
```
Young adults (late teens to early 20s)
Males > Females (5:1)
```
171
Pathophysiology of Ankylosing Spondylitis
Inflammation settles
Calcium laid down, reducing flexibility of spine
Usually starts in sacroiliac joints and spreads upwards
172
Conditions associated with Ankylosing Spondylitis
IBD
Psoriasis
Reactive Arthritis
173
Symptoms of Ankylosing Spondylitis
Stiffness in lower back in the morning that eases throughout the day.
Pain in sacroiliac joints, buttocks/thighs
Associated with eye (Uveitis) and bowel (IBD) problems
174
Treatment for Ankylosing Spondylitis
```
Steroids
NSAIDs
Anti TNF
Physiotherapy
Daily Exercise
```
175
Pathophysiology of Paget's Disease
Increased osteoclastic bone reabsorption
Results in compensatory formation of new bone which is weaker.
Leads to deformity and increased risk of fracture
176
Presentation of Paget's Disease
Bone and joint pain
Deformities e.g. bowed legs
Neurological complications:
- nerve compression e.g. CNVIII causing deafness
- Spinal stenosis
- Hydrocephalus (blockage of Aqueduct of Sylvius)
177
Cause of Osteomalacia
Vitamin D deficiency
Can be dietary, due to reduced sunlight or GI disease causing reduced absorption
178
Symptoms of osteomalacia
Muscle weakness (causing a waddling gate)
Bone pain - a dull ache, worse when walking
179
Symptoms of neoplastic bone disease
Local bone pain
Systemic symptoms (malaise and pyrexia)
Aches and pains due to hypercalcaemia
180
Most common bone metastases come from...
Breast, bronchus and prostate cancers
181
Pathophysiology of osteoporosis
Increased bone breakdown by osteoclasts
| Decreased bone formation by osteoblasts
182
Nerve roots of sciatic nerve
L4-S3
183
Symptoms of sciatica
Low back pain
Buttock pain
Pins and needles
Numbness and pain/weakness in leg and foot
184
Causes of sciatic
Pregnancy (increased pressure)
Herniated disc
Spinal stenosis
Piriformis Syndrome
185
Piriformis Syndrome
Where sciatic nerve runs through piriformis, not below it
186
Treatment for Piriformis Syndrome
Botulinum Toxin injection
187
Symptoms of Cauda Equina Syndrome
```
Saddle anaesthesia/paraesthesia (near anus and genitals)
Sexual, bladder and bowel dysfunction
Severe back pain
Sciatica
Loss of ankle reflex
Paraplegia of legs
Gait disturbance
```
188
Nerve roots associated with saddle anaesthesia in Cauda Equina Syndrome
S3-5
189
Pathophysiology of Cauda Equina Syndrome
Compression/Damage to L1-L5 and S1-S5
190
Treatment of Cauda Equina Syndrome
Emergency surgical decompression
191
Upper motor neurones originate in...
Precentral gyrus
Primary motor cortex
192
LMNs are found in....
Anterior grey column
Anterior nerve roots
Cranial Nerve nuclei
193
Alpha motor neurones
In extrafusal muscle fibres
194
Beta motor neurones
In extrafusal and intrafusal muscle fibres
195
Gamma motor neurones
Intrafusal fibres and muscle spindles for proprioception
196
Causes of UMN Lesions
Stroke
MS
Cerebral palsy
Other acquired brain injury
197
Causes of LMN lesions
```
Trauma to peripheral nerves causing severance of axons
Disease atrophy of muscle
Polio
Guillian Barre
Amyotrophic Lateral Sclerosis
```
198
Symptoms of UMN Lesions
```
Decreased strength
Increased tone (Spastic paralysis)
Clonus
Hypereflexia
Babinski sign
```
199
Symptoms of LMN Lesions
```
Decreased strength
Decreased tone (flaccid paralysis)
Fasciculations/Fibrillations
Hyporeflexia
Atrophy of muscle
```
200
Babinski sign occurs in...
UMN lesions
201
Loss of muscle mass occurs in (UMN/LMN) Lesions
Lower
202
Hypereflexia occurs in (UMN/LMN) Lesions
Upper
203
Neurotransmitter which transmits signals from upper to lower motor neurons
Glutamate
204
Physiological role of PGHS 1
GI tract
CNS
Platelets
205
Pathophysiological role of PGHS 1
Chronic pain
| Hypertension
206
Physiological role of PGHS 2
Renal
Platelet
Vascular system
Reproductive system
207
Pathophysiological role of PGHS 2
```
Inflammation
Chronic pain
fever
Vascular permeability
Angiogenesis
Tumour growth
Neurodegeneration
```
208
MOA of NSAIDs
Inhibit COX domain of PGHS
Reduces PGE2
209
Effect of PGE2
Sensitised A-delta and C nociceptive fibres to 5-HT, bradykinin and substance P
**Transmission of pain**
210
Effect of aspirin on blood
Inhibits platelet aggregation and clotting due to irreversible inhibition of COX 1
211
MOA of Aspirin
Irreversible inhibition of COX domain of PGHS
212
Why do NSAIDs cause renal failure?
Inhibition of COX2 which produces prostaglandins which cause vasodilation in renal blood vessels
213
Indication for rofecoxib
Osteoarthritis
214
MOA of rofecoxib
NSAID
| Selective inhibition of PGHS2
215
Why can Aspirin not be given to children?
Damages mitochondria in liver
Reye's:
Causes feve, rash, dizziness, brain problems, fatty liver, coma and death.
216
Reye's
Caused by Aspirin administration in <16yo
Causes feve, rash, dizziness, brain problems, fatty liver, coma and death.
217
Indication for naloxone
Opioid overdose
218
ADRs of morphine
Respiratory depression (decreased sensitivity of respiratory centre to pCO2)
Bronchoconstriction (causes histamine release from mast cells)
Constipation
219
Effect of mu opioid receptor activation
Analgesia
Euphoria
Respiratory depression
Dependence
220
Effect of kappa opioid receptor activation
Some spinal analgesia
Small sedation and dysphoria
No dependence or unwanted ADRs
221
How does opioid receptor activation inhibit neurotransmitter release?
Activation of opioid receptor (a GPCR) causes inhibition of adenylyl cyclase.
Causes K+ channels to open (hyperpolarisation occurs)
Inhibits Ca2+ channels in presynaptic cleft
No release of neurotransmitter
222
MOA of Tramadol
Weak agonist of mu-opioid receptors
| Inhibitor of NA reuptake (may have psychiatric reactions)
223
Components of a nerve block injection
Local anaesthetic e.g. lidocaine
Adrenaline
Corticosteroid
Opioid
224
Paresis means..
Weakness
225
Plegia means...
Paralysis
226
Duration of action of lidocaine as an LA
10-20mins
227
Duration of action of bupivacaine
2-8hrs
228
Onset of action of lidocaine occurs after...
1.5 mins
229
Onset of action of bupivacaine occurs after...
15 mins
230
Maximum dose of lidocaine
3mg/kg
231
Maximum dose of bupivacaine
2mg/kg
232
Maximum dose of lidocaine with adrenaline
7mg/kg
233
Maximum dose of bupivacaine with adrenaline
5mg/kg
234
Characteristics of non depolarising neuromuscular blockade
Longer duration f onset
Lasts longer (20 mins)
235
Characteristics of depolarising neuromuscular blockade
Fast acting
Shorter duration (10 mins)
236
MOA of Atracurium
Non depolarising neuromuscular blockade.
| Competitive antagonist of ACh receptor
237
MOA of Suxamethonium
Depolarising neuromuscular blockade
| Competitive agonist of ACh
238
Effect of Suzamethonium
Fasciculations for 30-40s
| Become paralysed when ca2+ runs out
239
MOA of botulinum in neuromuscular blockade
Inhibits ACh release at synapse
240
Characteristics of Botulinum when used in neuromuscular blockade
Long acting
| Temporary
241
Indication for botulinum (neuromuscular blockade)
Cerebral palsy patients
Post stroke
- Reduces contractures
242
Benefits of paralysing patients for surgery
Stops breathing - easier in abdominal surgery
Releases tension in muscles
Easier to intubate (relaxation of muscles around mouth and throat)
243
Neurapraxia
Damage to myelin sheath, conduction is slowed
244
Axonotmesis
Axon has been damaged
| No conduction
245
Neurotmesis
No conduction
246
Classification of Nerve Injury: Sunderland I
Myelin sheath damaged
| Slow conduction
247
Classification of Nerve Injury: Sunderland II
Loss of axonal continuity, endoneurium intact
248
Classification of Nerve Injury: Sunderland III
Loss of axonal and endoneurial continuity
| Perineurium intact
249
Classification of Nerve Injury: Sunderland IV
Loss of axonal, endoneurial and perineurial continuity
250
Classification of Nerve Injury: Sunderland V
Nerve trunk divided
| No conduction
251
Wallerian Degeneration
Degeneration of axon distal to injury
| Anterograde/orthograde
252
Neurotropism
Nerve endings send out neurotrophic factors which lure degenerated end to grow towards it
253
Rate of regeneration of neuron axons
1mm/day
254
Neuroma
Ball of raw ends of nerve fibres
255
Tinel's sign
Tapping on a nerve to initiate a response
| Causes an electric shock sensation occurs at site of injury
256
Advancing Tinel's
After 30 days recovery, how far from the location of original injury should the electric shock sensation be felt?
3cm
257
Surgery required for class IV and V neuron injury
Repair/Graft
258
Surgery required for class III neuron injury
Internal neurolysis (or none at all)
259
Which class of neuronal injury does Advancing Tinel's Sign occur in?
II and III
260
Which class of neuronal injury does Tinel's sign occur in?
II-V
261
Fibres responsible for proprioception in golgi tendon organ
Ia, Ib or II
262
Muscles spindles detect
Change in length/stretch
263
Primary sensory endings
Type Ia fibres
264
Secondary sensory endings
Type II fibres
265
Golgi tendon reflex
Feedback mechanism to control muscles tension.
| Prevents muscle tension being so high that the tendon will tear.
266
Wallerian Degeneration is mediated by...
Ca2+
267
Chromatolysis
When Nissl bodies (made up of RER in cell body) are damaged and begin to swell 10-20 days after injury
268
How does chromatolysis act as a signal?
Signals to glial cells to help with recovery
269
How does the body synthesis biologically active vitamin D?
Cholesterol converted to vitamin D3 in skin due to UV light
Liver converts this to calcifediol.
Kidneys convert this to caliol (biologically active)
270
Effects of calcitriol
Increases plasma calcium by:
Increased absorption from GI tract
Increased release from bone via osteoclasts
271
Overall effect of PTH
Increased plasma calcium
272
How does PTH increase plasma calcium?
Activates osteoclasts
Increased Ca2+ reabsorption in kidneys
Increases production of calcitriol (therefore Ca2+ absorption from GI tract)
273
Calcitonin is produced by...
Thyroid gland
274
Overall effect of calcitonin
Decrease plasma calcium
275
How does calcitonin decrease plasma calcium?
Inhibits osteoclasts
Activates osteoblasts
Inhibits absorption of Ca2+ in kidney and GI tract
276
Medical uses of calcitonin
Hypercalcaemia
Paget's Disease
Bone metastases
277
Diaphysis
Shaft of a bone
278
Epiphysis
Ends of a bone
279
Vokmann's Canals
At 90 degrees to Haversian Canals
| Connect osteons
280
Periosteum is made of
Dense irregular connective tissue
281
Resorption phase of bone remodelling
Osteocytes release chemical transmitters/chemoattractants OR undergo apoptosis.
Encourages osteoclasts to undergo apoptosis (takes 3-5 weeks)
282
Reversal phase of bone remodelling
Osteoblasts activated and mature when osteoclasts are apoptosed.
Osteoblasts begin to secrete osteoid
283
Formation phase of remodelling
Osteoid and matrix is mineralised
Osteoblasts become resting bone.
Bone is quiescent again (inhibition of osteoclasts and osteoblasts)
284
Osteonectin
Anchors bone to collagen
285
Composition of hyaline cartilage
Water
Proteoglycans
Type II Collagen
Chondrocytes
286
Osteoblasts secrete...
Osteoid and collagen
287
Osteoclasts secrete...
Carbonic Anhydrase
288
How do osteoclasts cause breakdown of bone?
Secretion of carbonic anhydrase which acidifies the matrix.
| Causes it to decalcify
289
Primary hyperparathyroidism causes what change in blood?
Hypercalcaemia
290
Symptoms of hypercalcaemia due to hyperparathyroidism
Bone pain/fracture
Kidney stones
Abdominal pain (due to constipation, indigestion, nausea and vomiting)
Psychiatric problems
291
Hypoparathyroidism causes what change in blood?
Hypocalcaemia
292
Symptoms of hypocalcaemia due to hypoparathyroidism
```
Muscle spasm (tetany)
Paraesthesis around mouth/feet
```
293
For the first 4-5 days after a bone fracture...
```
Phagocytic cells (macrophages) remove debris
Granulation tissue forms
```
294
What is granulation tissue?
Loosely gelled protein-rich exudate which later is fibrosed into scar tissue.
Forms 4-5 days after a bone fracture.
295
How long does the inflammation phase of bone healing last?
Minutes to days
296
Inflammation phase of bone healing:
Formation of haematoma for stability.
| Increased permability of capillaries so that inflammatory mediators are released.
297
Repair phase of bone healing:
Osteoblasts migrate to site of injury and secrete osteoid into granulation tissue.
Forms a soft callus which is ossified to a hard callus.
298
Remodelling phase of bone healing:
Restructuring of hard callus by osteoblasts and osteoclasts.
| Formation of periosteum
299
Fibrous union occurs following bone fracture due to...
Improper immobilisation
300
Effect of delayed union following bone fracture
Healing takes 2x longer than normal
301
Where is non union of a healing fracture common?
Scaphoid
302
Malunion of a healing fracture
Has healed incorrectly
| Twisted/rotate/shortened/bent
303
Risk factors for osteoporosis
```
Female
Age
Genetic predisposition
Alcohol
Smoking
Unfit
Low oestrogen
```
304
Diagnosis of osteoporosis
DEXA
>2.5 standard deviations below normal bone density (T score)
305
Non pharmacological management of osteoporosis
Exercise
Calcium and vitamin D supplementation
Cessation of smoking
Reduce alcohol intake
306
First line drugs for osteoporosis
Bisphosphonates:
Alendronate
Risedronate
Ibandronate
307
Ratio of matrix to bone in osteoporosis
Normal
308
Ration of matrix to bone in osteomalacia
Decreased
309
Amount of bone in osteoporosis is (decreased/normal)
Decreased
310
Amount of bone in osteomalacia is (decreased/normal)
Normal
311
Treatment of osteomalacia/rickets
Oral vitamin D2/3
312
Symptoms of rickets
```
Genu varum (bowing femurs)
Bone tenderness
Muscle weakness
Tetany (muscle spasms)
Hypocalcaemia
```
313
Blood tests in Paget's Disease
Normal Ca2+, vitamin D, PTH and phosphate.
Increased alkaline phosphatase
314
Treatment of Paget's Disease
Bisphosphonates:
Risedronate
Zolendronate
Alendronate
Ibandronate
315
Acute Spinal Cord Injury -
| Frankel's Type A
No motor or sensory function below level of injury
316
Acute Spinal Cord Injury - Frankel's Type B
No motor function and sensory preservation below level of injury
317
Acute Spinal Cord Injury - Frankel's Type C
Useless motor function below level of injury
318
Acute Spinal Cord Injury - Frankel's Type D
Useful motor function below level of injury
319
Acute Spinal Cord Injury - Frankel's Type E
Normal motor and sensory function
320
Effect of spinal cord injury C1-C3
Requires ventilators for breathing (due to loss of phrenic nerve)
321
Effect of spinal cord injury C4-T1
Loss of arm function
322
Effect of spinal cord injury T1-T8
Lose control of abdominal muscles and trunk stability
323
Effect of spinal cord injury T9-T12
Partial loss of trunk and abdominal muscle control
324
Effect of spinal cord injury in lumbosacral region
Loss of control of legs, urinary system and anus.
| May affect sexual function.
325
When looking at X-rays of cervical spine, we assess:
```
T1/C7 junction
Alignment
Vertebrae
Odontoid peg
Soft tissue
```
326
Ideal imaging view for odontoid peg fracture
Open mouth
327
What does an peg/dens fracture look like on an X-ray?
Ring of C2 is incomplete
328
Hangman's Fracture
Fracture of pedicles of C2
| Body and dens displaced anteriorly
329
Teardrop fracture
Hyperextension causing displacement of anterior part of vertebral body.
Usually of C2
330
Most common cause of anterior cord syndrome
Ischaemia/Infarction of anterior spinal artery (supplies anterior 2/3 of spinal cord)
331
Effect of anterior spinal cord syndrome
Bilateral spastic paralysis below level of injury.
Loss of pain/temp/light touch sensation below level of injury.
Sacral sparing.
332
Most common cause of Posterior Cord Syndrome
Tumor(s) pressing on spinal cord
333
Effect of posterior cord syndrome
Loss of proprioception, vibration and 2 point discrimination below level of injury.
Motor preservation
334
Cause of central cord syndrome in elderly
Degenerating IV discs in spondylosis causing compression of vessels.
Centre of spinal cord is at highest risk of ischaemia.
335
Effect of central cord syndrome
Profound motor weakness (in upper limbs more than lower)
Varying degree of sensory loss below level of lesion.
Urinary retention.
Sacral sparing
336
What is Brown-Sequard?
Hemicord lesion - damage or impairment to left or right side of spinal cord.
337
Causes of Brown-Sequard
Penetrating injury
Disc herniation
Vertebral artery dissection
338
Effect of Brown-Sequard
Ipsilateral loss of proprioception, vibration and light touch sense.
Ipsilateral spastic paralysis
Contralateral loss of pain and temperature sense.
339
Why does ipsilateral loss of proprioception and vibration sense occur in Brown-Sequard?
Dorsal column is responsible for this sensation.
Crosses over in spinal cord higher up in the spinal cord.
Therefore, sensory impulses on the side of the lesion will not reach the brain.
340
Why does ipsilateral spastic paralysis occur in Brown-Sequard?
Corticospinal tract is responsible for motor function.
Crosses over higher up in spinal cord.
Therefore, motor impulses travelling to limbs on the the side of the lesion will not reach their target.
341
Why does contralateral loss of pain and temperature sensation occur in Brown-Sequard?
Spinothalamic Tract is responsible for this sensation.
Crosses over immediately in spinal cord.
Therefore, sensory impulses on the opposite side to the lesion will not reach the brain.
342
Spondylolisthesis of C2 is also known as
Hangman's Fracture
| Forward displacement of C2
343
Disc Herniation in children is associated with...
Fracture of vertebral ring apophysis.
| Common in young athletes.
344
Commonest tumor in bone
Metastases
345
Commonest primary tumor in bone
Myeloma
346
Common primary tumors in bone
Myeloma and osteosarcoma
347
Myeloma
Arises in plasma cells in blood when they start releasing paraprotein antibody.
348
Sarcoma
Cancers which arise in supporting tissue (connective or other non epithelial tissue)
349
Osteosarcoma most commonly occurs in...
Teenagers as their bones are growing.
| More commonly arms or legs.
350
Vertebra prominens
C7
351
How does breast cancer metastasise to spine?
Azygous venous plexus (to thoracic spine)
352
How does prostate cancer metastasise to the spine?
Pelvic venous plexus (to lumbar spine)
353
How does lung cancer metastasise to the spine?
Segmental arteries
354
How does pancreatic cancer metastasise to the spine?
Direct spread
355
Batson Venous Plexus
Valveless veins
Connect pelvic and thoracic veins
Low intraluminal pressure
Common route of spread of cancer.
356
Microbes commonly responsible for Spinal Infections
60% Staph aureus
30% Enterobacter
(+ TB, Fungi, salmonella)
357
Risk factors for spinal infection
```
Age (teens and elderly)
Immigrants
Diabetes
Renal failure
Spinal surgery
Rheumatoid Arthritis
Steroids/Immunosuppression
```
358
Spinal TB causes...
Cord compression
| Destruction of vertebral bodies and disc spaces w/ local spread of infection
