Locomotion Flashcards
(153 cards)
1
Q
There are no anastamoses between epiphyseal and metaphyseal vessels until skeletal maturity is reached. Why?
A
Due to growth plate blocking anastamoses formation
2
Q
Drainage of cortical bone occurs where?
A
Periosteal venules
3
Q
What makes up the bone matrix?
A
Collagen (type I)
Glycoproteins
Hydroxyapatite (calcium and phosphate)
4
Q
Which bone cell type is thought to have a role in the sensing of mechanical strain?
A
Osteocytes. They have fine processes extending into canaliculi which form junction with processes from other cells
5
Q
Which bone cell type is multinucleate? What do these cells do?
A
Osteoclasts
Secrete hydrogen ions and lysosomal enzymes to degrade bone matrix.
6
Q
What is the sealing zone in bones?
A
Adhesion between osteoclasts and bone.
7
Q
What type of nerve branches do Haversian canals have?
A
Vasomotor and sensory nerves
8
Q
What is a volkmann’s canal?
A
Transverse blood vessel joining two Haversian canals
9
Q
Where are osteoblasts and osteoclasts derived?
A
Osteoblasts: mesenchymal cells
Osteoclasts: haemopoietic cells (form mononucleate preosteoclasts)
10
Q
In which domestic species are secondary ossification centres present at birth?
A
Ungulate species
11
Q
What part of the femur ossifies the quickest and what part the slowest?
A
Femoral head is the quickest
Lesser trochanter is the slowest
12
Q
Growth in bone length happens though which mechanisms? How about expansion of the epiphysis?
A
Chondrocyte proliferation in the growth plate
Chondrocyte proliferation in the articular-epiphyseal growth cartilage
13
Q
Explain how remodelling occurs within cortical bone.
A
Osteoclasts tunnel through longitudinally
Osteoblasts follow and deposit concentric lamellae of bone
14
Q
What factors stimulate osteoblasts activity?
A
Sex steroid hormones
BMPs/growth factors
Mechanical load
Infl. cytokines and prostaglandins
15
Q
What factors stimulate osteoclast activity?
A
Mechanical unloading
Infl. cytokines and prostaglandins
PTH
(Effects mediated by osteoblasts through RANKL)
16
Q
What are the four steps in fracture repair?
A
- Inflammation (haematoma—>infl mediators—>mesenchymal cells)
- Soft callus formation (mesenchymal cells—>chondrocytes/fibroblasts—>fibrocartilaginous plate)
- Hard callus formation (endochondral ossification)
- Remodelling (mineralised bone matrix)
17
Q
What is interstitial growth?
A
Proliferation of chondrocytes resulting in pairs of chondrocytes within the same lacunae
18
Q
What substances make up the extracellular matrix of cartilage?
A
▪️Type 2 collagen
▪️amorphous material
▫️proteoglycans (core protein and sulphate glycosaminoglycans) and hyaluronan (a non-sulphate GAG)
19
Q
What characteristic of GAGs help it to resist compression?
A
They have multiple negative charge making the, strongly hydrophilic. Swelling pressure of proteoglycan aggregates helps resist compression and is resisted itself by tension in the type 2 collagen fibres
20
Q
Which cartilage types have a perichondrium?
A
Hyaline and elastic
21
Q
Hyaline cartilage has a high or low ratio of GAGs to collagen? What about fibrocartilage?
A
Hyaline: high
Fibro: low
22
Q
Chondrocytes are arranged in columns in which type of cartilage?
A
In growth plate of hyaline cartilage and in fibrocartilage
23
Q
Chondrocyte proliferation is stimulated by what factors? What inhibits it?
A
Growth hormone which acts through insulin-like growth factor (IGF-1) and BMPs
Inhibited by fibroblast growth factor
24
Q
What stimulates cartilage matrix secretion?
A
IGF-1 and BMPs
25
What stimulates chondrocyte hypertrophy? What inhibits it?
Thyroid hormones acting through IGFs and FGFs and through inhibition of parathyroid hormone-related peptide
26
What does vascular endothelial growth factor stimulate?
Angiogenesis
27
What stimulates osteoblasts and osteoclast differentiation?
Osteoblasts: BMPs
Osteoclasts: RANKL
28
A mutation in Aggrecan results in what?
| How about FGF4?
Aggrecan—> bulldog dwarfism in dexter cattle
| FGF4–> short legs in dogs
29
What is micromelia?
Poorly developed limb
30
What is chondrodystrophy? What does it result in?
Disorder of bone growth due to primary lesions in growth cartilage. Results in disproportionate dwarfism.
31
What are some examples of chondrodysplasia?
Spider lamb syndrome (reduced inhibition of chondrocyte proliferation). Autosomal recessive condition
Bulldog calves (dexter and Holstein cattle)
Mushroom shaped long bones in Alaskan malamutes and thickened physes
32
What is the hallmark lesion of osteochondrosis?
Focal or multi focal retention of growth cartilage due to failure to become mineralised and replaced by bone.
33
What may cause acquired osteopetrosis?
BVD, FeLV, canine distemper
34
What are some nutritional causes of osteoporosis?
Vit C, calcium, copper or phosphorus deficiency
Hypoproteinaemia
Hypervitaminosis A
35
What are some endocrine disorders that may result in osteoporosis?
Hyperthyroidism
| Hyperadrenocorticism (glucocorticoids inhibit collagen synthesis and stimulate bone resorption)
36
What are the two most common causes of rickets?
Vit D deficiency and phosphorus deficiency
37
Fibrous osteodystrophy is seen with what condition? Why?
Hyperparathyroidism due to increased PTH and hypercalcaemia resulting in widespread mineralisation
38
What lesions are produced by vit A toxicity?
Physeal damage
Osteoporosis
Exostoses
39
What are the routes through which infectious osteomyelitis may occur?
Haematogenous
Direct
Extension (locally from adjacent structures)
40
What are some anatomical factors favouring metaphyseal localisation of infectious osteomyelitis?
Capillaries make sharp loops
Capillaries are fenestrated and cause slow blood flow, thrombosis and necrosis
Phagocytosis in sinusoids is inefficient
41
Where are osteosarcoma most likely to metastasise?
The lungs
42
In the dog, what areas are most common,y affected with Marie’s disease?
Radius, ulna, tibia, metacarpals and metatarsals
43
What is micromelia?
Poorly developed limb
44
What is chondrodystrophy? What does it result in?
Disorder of bone growth due to primary lesions in growth cartilage. Results in disproportionate dwarfism.
45
What are some examples of chondrodysplasia?
Spider lamb syndrome (reduced inhibition of chondrocyte proliferation). Autosomal recessive condition
Bulldog calves (dexter and Holstein cattle)
Mushroom shaped long bones in Alaskan malamutes and thickened physes
46
What is the hallmark lesion of osteochondrosis?
Focal or multi focal retention of growth cartilage due to failure to become mineralised and replaced by bone.
47
What are some nutritional causes of osteoporosis?
Vit C, calcium, copper or phosphorus deficiency
Hypoproteinaemia
Hypervitaminosis A
48
What are the two most common causes of rickets?
Vit D deficiency and phosphorus deficiency
49
Fibrous osteodystrophy is seen with what condition? Why?
Hyperparathyroidism due to increased PTH and hypercalcaemia resulting in widespread mineralisation
50
What are the routes through which infectious osteomyelitis may occur?
Haematogenous
Direct
Extension (locally from adjacent structures)
51
What are some anatomical factors favouring metaphyseal localisation of infectious osteomyelitis?
Capillaries make sharp loops
Capillaries are fenestrated and cause slow blood flow, thrombosis and necrosis
Phagocytosis in sinusoids is inefficient
52
Where are osteosarcoma most likely to metastasise?
The lungs
53
What may cause acquired osteopetrosis?
BVD, FeLV, canine distemper
54
What are some endocrine disorders that may result in osteoporosis?
Hyperthyroidism
| Hyperadrenocorticism (glucocorticoids inhibit collagen synthesis and stimulate bone resorption)
55
In the dog, what areas are most common,y affected with Marie’s disease?
Radius, ulna, tibia, metacarpals and metatarsals
56
Where is the coracoid process located?
Medial aspect of the supraglenoid tubercle
57
Where are the proximal palmar sesamoids located in the dog forelimb?
Paired set on metacarpophalangeal joints II-V.
| Single one on metacarpophalangeal joint I
58
What are the boundaries of the pelvic inlet?
```
The promontory (dorsal margin)
Cranial border (pecten) of the pubis (ventral margin)
Arcuate lines extending from the auricular surface on the medial aspect of the ilium to the iliopubic eminence
```
59
What are the boundaries of the pelvic outlet?
Dorsally: first caudal vertebrae
Laterally: sacrotuberous ligament
Ventrally: caudal border of the ischiatic tuberosities and the ischiatic arch
60
In which species is the radius and ulna fused?
Ox and horse
61
Where is hyaline cartilage found?
Respiratory tract
Ventral ends of ribs
Articular cartilage
Growth plates of growing long bones.
62
In which locations does hyaline cartilage have a perichondrium?
All locations it is found except articular cartilage and growth plate
63
Where is fibrocartilage found? Does it have a perichondrium?
Intervertebral discs
Menisci
Points of attachment of tendons and ligaments to bone
Cardiac skeleton
No perichondrium
64
How does intramembranous ossification occur?
Aggregation of mesenchymal stem cells -> osteoblasts -> secrete osteoid -> spicules -> trabeculae formation
65
Which ossification centres of bones are present at birth and in which species?
Primary centres are present before birth in all domestic mammals.
Secondary centres are present at birth in ungulates but not in dog and cat.
66
How does growth in bone length occur? How about expansion of the epiphysis?
Through proliferation of chondrocytes in the growth plate
Proliferation of chondrocytes in articular epiphyseal growth cartilage.
67
How are bending forces best neutralised in bone?
By placing implant in neutral axis of bone
| Intermedullary rods
68
Which bones or parts of bone are susceptible to tension forces?
Olecranon
Calcaneous
Tibial tuberosity
Greater trochanter
69
Bulldog calves are usually seen with what breed?
Dexter and Holstein cattle 🐄
70
What is the initiating cause of osteochondrosis?
Focal disruption of vascular supply in growing animals which causes a focal area of cartilage necrosis and chondrolysis
71
What is osteochondrosis dissecans?
Disorder of endochondral ossification.
Osteochondrosis where the clefts cause extensive underrunning of the articular cartilage often creating a flap which can separate from the surface.
72
What are some potential causes of osteochondrosis?
```
Genetic predisposition
Trauma
Rapid growth
Excess dietary calcium and copper deficiency
Hormonal imbalances
```
73
What is inherited osteopetrosis?
Defect of osteoclastic function which leads to poor remodelling of the primary trabeculae and subsequent increased bone fragility
74
What anatomic factors favour metaphysical localisation of bacteria leading to osteomyelitis?
▪️Capillaries make sharp loops
▪️Capillaries are fenestrated and open into sinusoidal vessels which causes sluggish blood flow, thrombosis and necrosis
▪️Phagocytosis in sinusoids is inefficient
75
What is a sequestrum? What about an involucrum?
Sequestrum: bone that had become separated from surrounding tissue due to necrosis
Involucrum: Denser ring of reactive tissue surrounding sequestrum
76
Which fibres types are predominantly affected with the following causes of atrophy?
- denervation
- disuse
- endocrine
- congenital myopathy
- malnutrition
- denervation: 1 and 2
- disuse: 2
- endocrine: 2
- congenital myopathy: 1
- malnutrition: 2
77
What do most cases of arthrogryposis result from?
What are some potential causes of this?
What animals is it mostly seen in?
Defective innervation of muscles
Genetic defects
Teratogenic viruses
Teratogenic toxins
Nutritional deficiencies
Lambs, calves, piglets and foals
78
What is heritable myotonia?
A condition in angora goats, chow chows and miniature schnauzers characterised by a temporary inability of muscle fibres to relax.
Due to a mutation of a chloride channel gene leading to prolonged contraction post depolarisation.
79
What is myasthenia gravis? What are some clinical signs? What are the two forms?
Neuromuscular disorder characterised by muscle weakness exacerbated by exercise.
See a choppy stride and then recumbent for a bit. May also manifest as a hoarse bark/miaow, facial muscle weakness, pupillary dilation, megaoesophagus.
Congenital: (JRT, Springer spaniels, smooth Fox terriers). Decreased Ach receptors in muscle membranes (see at 5-8weeks old)
Acquired: immune mediated with Abs directed against Ach receptors of neuromuscular junctions
80
Which muscle fibres types typically atrophy with disuse? What about with denervation?
Disuse: type 2
Denervation: type 1 and 2
81
What are the steps involved in muscle regeneration?
Muscle injury-> inflammation-> regeneration (satellite cell activation and division)-> remodelling-> maturation and functional repair
82
How does myofibre repair occur if the sarcolemma tube is disrupted?
Budding or by fibrosis
83
What are muscular dystrophies? What is duchenne muscular dystrophy?
Rare inherited primary muscle disorders characterised by progressive myofibre degeneration with inadequate or ineffective regeneration.
DMD is an x-linked recessive disorder in which there is a defective or deficient dystrophin complex leading to physical trauma to muscle fibres
84
What is malignant hyperthermia?
Acute syndrome in which drugs, stress or caffeine lead to unregulated release of calcium leading to excessive contraction and heat production
85
Explain the process of muscle crush syndrome following a traumatic laceration of the muscle.
Laceration-> haemorrhage, oedema, hyperaemia and inflammation-> increased intramuscular pressure-> necrosis
86
What is white muscle disease?
| What triggers it?
Nutritional myopathy affecting sheep, cattle and pigs due to a deficiency of vitE and/or selenium
Triggered by rapid growth, unaccustomed exercise, cold weather etc.
(Affects type 1 fibres)
87
What are the consequences of superficial cartilage injury? What about deep?
Supfl: if they don’t approach the tidemark zone, there will be mitotic division of adjacent chondrocytes. Doesn’t heal completely
Deep: also stimulates mitotic division. More importantly, there is invasion of fibrovascular granulation tissue aka a pannus
88
Why is pannus formation in bone undesirable?
Because it interferes with diffusion of nutrients into articular cartilage and can cause erosion/ulceration and destruction of cartilage and bone because it has collagenolytic activity
89
Adhesion of a pannus to an apposing articular surface is termed....?
Fibrous ankylosis
90
What is the common sequence of degeneration in injured synovial joints?
1. Chondromalacia
2. Cartilage fibrillation
2a. Horizontal splits
3. Eburnation
3a. Linear grooves
91
What is the earliest grossly visible change with joint degeneration?
Cartilage fibrillation
92
In which conditions is synovial villous hyperplasia most extreme?
Suppurative arthritis and immune-mediated arthritis
93
Where do periarticular osteocytes commonly arise?
At or near the transitional zone of the synovium
94
In which domestic species are subchondral bone cysts most commonly seen?
Horses
95
Degenerative joint disease is common in all domestic animals except...? What is the difference between primary and secondary DJD?
Sheep and cats
Primary: no apparent predisposing cause
Secondary: predisposing cause identified
96
Arthropathy of the bovine stifle is a DJD affecting cows. In which breeds is it possibly inherited? What aspect of the limb is mostly affected?
Fresians and Jerseys
| Medial aspect
97
Bone spavin affects which joints? What about high ringbone?
Spavin: intertarsal joints of horses especially medially
Ringbone: pastern joints especially those of the FL
98
How do repeated episodes of haemarthrosis affect the joint?
The positive Fe charge of the Hb neutralizes the negative charge of the proteoglycans leading to increased permeability of the blood synovial barrier. This allows large plasma proteins to enter the joint cavity leading to cartilage erosion and DJD
99
In what species is infectious arthritis especially common?
Livestock (especially young animals)
100
With most agents causing infectious arthritis, what type type of inflammatory exudate is present in the joint? In what cases is this different?
Most often serofibrinous to fibrinous. However with arcanobacterium pyogenes and other pyogenic staphylococci, we see suppurative inflammation
101
What is a phlegmon?
Extension of pus into periarticular tissues
102
What are the two forms of immune mediated arthritis?
1. Erosive: antigen triggering inflammation is present in the synovium
2. Non-erosive: the primary disorder is extra-articular
103
What is SLE?
Condition in which auto antibodies are directed against DNA with Ab-Ag complexes deposited intermittently in blood vessel walls
104
What is hygroma? In which animals is it seen?
Carpal bursitis
| Common in cattle and sheep (and goats with caprine arthritis encephalitis virus)
105
What is fistulous withers? What about poll evil?
Fistulous withers= bursitis of the supraspinatus bursa between the nuchal ligament and the spinous process of T2 (sometimes 3,4 or 5)
Poll evil= bursitis of Atlanta’s bursa between nuchal ligament and atlas
106
From what cell are histiocytic sarcomas derived? Do they metastasise?
Langerhan’s cells
| Often metastasise to regional lymph nodes and occasionally lungs and other viscera
107
What is proprioception?
Position sense. Afferent input about the relative position of the body and its parts
108
Where are the following proprioceptors located in muscles:
- golgi tendon organs
- Muscle spindles
- Golgi tendon organs are present in tendons and report muscle tension dvpt
- Muscle spindles are embedded within the muscle and report muscle position (stretch)
109
Where does local afferent input come from?
1. Skeletal muscles controlled by motor neurone
2. Other nearby muscles (esp. antagonists)
3. Tendons, joints and skin of body parts affected by muscle action
110
What do muscle spindles detect?
Rate of change and changes in muscle length
111
What is the difference between nuclear bag and nuclear chain fibres?
Nuclear bag: sense onset of stretch
Nuclear chain: sense sustained stretch
*both are activated with rapid stretch
112
What is the difference between gamma and alpha motor neurons?
Gamma: efferent neuron innervating intrafusal fibres
Alpha: efferent neurone innervating extrafusal fibres
113
What are the two types of muscle spindles nerve ending?
1. Primary: type 1a axons. Detect length changes and speed
| 2. Secondary: type 2 axons. Detect length changes only
114
What things are involved in the maintenance of posture and balance?
Reflexes (stretch and crossed extensor)
| Afferent pathways involving the eyes, vestibular apparatus and proprioceptors
115
How might bone fractures be classified?
According to their nature (traumatic, stress, pathologic), energy level (low, high, very high) or their completeness (complete/incomplete)
116
New bone can only form under ____% strain. Strain is high when....?
2%
| Strain is high when the change in length is high and the initial gap is small
117
What are some main differences between indirect and direct bone union?
Direct:
Requires anatomic alignment and absolute stability of fragments. Little to no fracture callus forms in direct bone union. It can be subdivided contact healing and gap healing.
Indirect:
Occurs when the strain is >2%. Results in callus formation to increase stability
118
What fracture conformations are the following forces likely to cause on a long bone?
- Compressive
- Bending
- Tensile
- Bending + compression
- Torsional
```
Compressive- oblique
Bending- transverse
Tensile- transverse
Bending and compression- butterfly
Torsion- spiral
```
119
How are torsional forces in fractures best neutralised?
Plate and screws, interlocking nail or external skeletal fixation
(Poorly resisted by intramed pins)
120
What re four functions of the cranial cruciate ligament?
1. Limit cranial subluxation of the tibia relative to the femur
2. Limit hyperextension of the stifle
3. Limit internal rotation of the tibia relative to the femur
4. Mechanoreceptor function- provides feedback to quadriceps and hamstrings
121
The synovial intima is composed of two main types of specialised synoviocytes. What are they?
Type A- phagocytic and APCs
| Type B- akin to fibroblasts and produce hyaluronan and matrix components. Can also secrete degrading enzymes.
122
What makes up the blood-synovial barrier?
Fenestrated synovial capillaries, synoviocytes and hyaluronan in their supporting storms
123
What is the articular epiphyseal complex?
Where the articular cartilage merges with the epiphyseal growth cartilage in immature animals.
124
In an adult, the articular cartilage plate is divisible into four zones. What are they?
1. Superficial gliding zone
2. Intermediate transitional zone (shock absorption)
3. Radiate zone
4. Mineralised zone (attached to SC bone)
125
What is the blue line or tidemark line?
Junction of radiate zone and mineralised zone seen histologically in the articular cartilage plate of mature animals
126
What are some examples of mediators of articular cartilage damage?
Lysosomal enzymes
Prostaglandin E2
Leukotrienes
IL-1
127
What is synovial chondromatosis?
Metaplastic structures arising from any part of the synovial membrane.
128
What commonly causes polyarteritis in neonatal livestock species?
Bacteraemia secondary to Omphalitis (navel-ill) or GI entry
129
Describe the stay apparatus of the hindlimb in a horse.
Medial patellar ligament “locks” over the medial trochlear ridge of the femur thereby supporting gene stifle joint against flexion
130
What are the attachments of the nuchal ligament?
In the horse: nuchal crest of occipital bone and dorsal spinous processes of first few thoracic vertebrae
In the dog: spinous process of the axis to dorsal spinous processes of first few thoracic vertebrae
131
How does the ruminant hoof differ to the horse hoof?
-no frog
Coronary papillae are smaller
Wider periople
More prominent heel bulbs
Stratum internum is less extensive with no secondary lamellae
Abaxial and axial walls are demarcated by respective groves
132
What comprises the stay apparatus of the equine hindlimb?
Medial patellar ligament
Reciprocal app (SDF and PT)
Suspension app
133
How do the patellar ligaments differ between the dog and horse?
The horse has a medial and lateral (and middle) patellar ligament in addition to the femoropatellar ligaments
134
What are some skeletal adaptations to bipedal hopping?
```
Increased tibia:femur ratio
Long and strong tail
Short FLs
Short cervical region
Long and wide lumbosacral and coccygeal vertebrae
Fibrocartilaginous patella
```
135
Explain how the following requirements for flight are dealt with.
Allow lift to overcome gravity
Reduce drag
Propulsion into air
Lightweight skeleton
Rigid compact body (fused thoracic vertebrae, rigid pect girdle)
Efficient muscular effort (birds: carpus and elbow flexion occur together, bats: elbow and digits extend/flex with shoulder)
136
What are the three layers comprising the neural tube?
Germinal, mantle (grey matter) and marginal layers (white matter)
137
What does the paraxial mesoderm form?
Condenses to form somites that then subdivide into sclerotomes
138
What are the three parts of the brain and what do they each comprise?
Forebrain=prosencephalon
- diencephalon (interbrain/ third ventricle)
- telencephlaon (cerebrum)
Midbrain= mesencephalon
Hindbrain=rhombencephalon
- myelencephalon (medulla oblongata)
- metencephalon (cerebellum and pons)
139
What are the meningal layers surrounding the CNS?
```
Bone
Fat in epidural space
Dura mater (encloses spinal roots)
Arachnoid mater and trabeculae
Pia mater
Spinal cord
```
140
Where does the fusion between the bone and dura mater occur? (i.e. no epidural space)
Between C2 and C4
141
What are the ligaments of the spinal column?
1. Denticulate (bw arachnoid and pia mater half way between successive spinal nerves)
2. Nuchal ligament (C2-T1 in dog)
3. Supraspinatus lig (T1-Cd3)
4. Ventral longitudinal ligament (axis-sacrum below body of vertebra)
5. Dorsal longitudinal ligament (dens-end of vertebral canal)
6. Interspinous ligament (connect vertebral spines)
7. Ligamentum flavum (bw arches of adjacent vertebrae)
8. Intercapital ligament (T2-T11
9. 1 transverse and 3 apical ligs of the dens
142
What spinal cord segments are in line with their associated vertebrae?
Where are the sacral segments aligned. What about the caudal segments?
T12 to L3
Sacral= L5
Caudal= L6
All the rest are 1 ahead of vertebrae
143
How many pairs of spinal nerves in a dog?
36 (8C, 13T, 7L, 3S)
144
What nerve innervates the skin over the following areas (autonomous zones)?
1. Digits 3 and 4 (FL)
2. Digits 2 and 3 (FL)
3. Abaxial digit 5 (FL)
4. Digits 2-4 (HL)
5. Digits 2 and 3 (HL)
6. Medial leg between stifle and tarsus
1. Digits 3 and 4 (FL)- radial n.
2. Digits 2 and 3 (FL)- median n.
3. Abaxial digit 5 (FL)- ulnar n.
4. Digits 2-4 (HL)- peroneal n.
5. Digits 2 and 3 (HL)- tibial n.
6. Medial leg bw stifle and tarsus- saphenous n.
145
What is a fasciculus or tract?
What is a funiculus?
What tracts are found in the dorsal, lateral and ventral funiculi?
Group of functionally similar fibres travelling together
Funiculus is a division of spinal cord white matter separated by dorsal and ventral spinal nerve roots
Dorsal- ascending proprioceptive
Lateral-ascending and descending tracts (flexors)
Ventral- descending tracts (extensors)
146
What are the differences between upper and lower motor neurones?
LMn connect CNS to periphery. uMN within CNS
147
Describe the path of conscious proprioception.
```
Travels to dorsal funiculus then...
Fasiculus cuneatus/gracilis
Medial cuneate/ gracilis nucleus (T8)
Medial lemniscus
Thalamus (where crossover occurs)
Cerebrum (somatosensory cortex)
```
148
How might a subconscious vs conscious proprioceptive deficit present in an animal?
Conscious- animal bears weight on abnormal part of foot
| Subconscious- abnormal limb position
149
Why is lower motor neurone damage more significant than upper motor neurone damage? If and UMN is damaged, what might we see?
UMNs from many different tracts may influence a single LMN
Exaggerated reflexes/ movements
150
What do subconscious proprioceptive pathways do?
Help coordinate posture and repetitive locomotory movements (spinocerebellar tracts)
151
What is an example of a motor tract involved in managing body responses to proprioception?
Which tract is responsible for pain and temp sensibility?
Vestibulospinal tract
Tectospinal tract
Lateral spinothalamic
152
What type of glial cells do you expect to find in grey matter?
Oligodendrocytes
Astrocytes
Microglial cells
Ependymal cells
153
What is the Nissl substance?
| What about the neuropil?
Rough ER, free ribosomes, polysomes in cytoplasm
Intermingled cell processes
