tOSU CVM Block 3 "Learning Objective"

Cerebellum Folium

surface ridges

Cerebellum Sulcus

grooves

Cerebellum Fissure

deep sulcus

Primary Cerebellum Fissure

separates rostral and caudal lobes

Caudolateral Cerebellum Fissure

separates caudal and flocculonodular (FN) lobes

Archicerebellum

What: ancient, smallest

Where: Flocculonodular (FN) lobe

Function: equilibrium, vestibulocerebellum

Paleocerebellum

What: old

Where: rostral lobe

Function: stereotypical/coarse movement, spinocerebellum

Neocerebellum

What: new, largest

Where: caudal lobe

Function: highly skills/fine motor, pontocerebellum

Deep cerebellar Nuclei

(MEDIAL)

1. fastigial

2. interpositive

3. dentate

(LATERAL)

**Extrapyramidal nuclei that control LMN**

Cerebellar Cortex

(SURFACE)

1. molecular (house parallel fibers)

2. Perkinje (turn on/off deep cerebellar nuclei)

3. Granule

(DEEP)

Body Nociception

Spinothalamic Tract

*VCL*

Head Nociception

quintothalamic tract

*VCM*

Spinothalamic Reflex (body nociception)

1* Neuron: located in Doral Root Ganglion

Lissauer (Dorsolateral Fasciculus) Tract

2* Neuron: mono or poly synaptic

3* Neuron: Lower Motor Neuron in Ventral Horn

Spinothalamic Relay (body nociception)

1* Neuron: in Dorsal Root Ganglion

Lissauer's Tract

2* Neuron: in Dorsal Horn **CROSSES OVER**

3* Neuron: Ventral caudal LATERAL nucleus

Internal capsule

Spinothalamic relay animals vs humans

in animals:

- diffuse

- multisynaptic

- bilateral

- not as discrete

Quintothalamic Reflex (head nociception)

1* Trigeminal Ganglion (forms spinal tract of Trigeminal Nerve)

2* Pointe Sensory Nucleus = mechanical stimuli

OR

2* Spinal Nucleus of Trigeminal Nerve = thermal/light touch stimuli

(2* CROSSES OVER)

3* LMN: GSE, GVE, or SVE

Quintothalamic Relay (head nociception)

1* Trigeminal Ganglion (forms spinal tract of Trigeminal Nerve)

2* Pointe Sensory Nucleus = mechanical stimuli

OR

2* Spinal Nucleus of Trigeminal Nerve = thermal/light touch stimuli

3* Neuron: Ventral Caudal MEDIAL nucleus

Internal capsule

Stationary Proprioception Test

paw flip

moving proprioception test

gait (circling)

Thoracic Proprioception

Conscious = Fasciculus Cuneatus

Subconscious = Cuneocerebellar (rostral spinocerebellar) Tract

Pelvic Proprioception

Conscious = Fasciculus Gracilis

Subconscious = Dorsal/Ventral Spinocerebellar Tract

Cuneate Nucleus

Medial = conscious thoracic proprioception

Lateral = subconscious thoracic proprioception

DRG =

Dorsal Root Ganglion = Body

TG =

Trigeminal Ganglion = Head

VCL =

Ventral Caudal Lateral Nucleus = Body

VCM =

Ventral Caudal Medial Nucleus = Head

Sensory Reflex =

Local

Mono or Poly Synaptic

Sensory Relay =

pathway to higher Nervous System

Macro structure of bone

(TOP of bone)

Epiphysis

Physis

Metaphysis

Diaphysis

Metaphysis

Physis

Epiphysis

(BOTTOM of bone)

Micro structure of Bone

Woven = Immature bone

Lamellar = mature bone (cortical/compact OR cancellous/spongy)

Bone cell organs and functions

osteoBLAST = mesenchymal stem cells; build bone

osteoCYTE = mature/trapped blast; communicate/regulate cells

osteoCLAST = hematopoietic stem cells; consume bone

inorganic component of bone

60-65% of total bone mass

minerals (calcium hydroxyl apatite)

Body's Mineral Reserve (99% Ca, 85% P, 65% Na/Mg)

Organic component of bone

35-40% of total bone mass

Bone multicellular unit (blast, cyte, class)

Extracellular Matrix (95% Type 1 collage + 5% ground sub)

vascular supply to bone

1. nutrient artery

2. periosteal capillaries

3. meta/epiphyseal vessels

describe nutrient artery

1-2 per bone

enters at nutrient foramen

branches proximal & distal

supplies medullary cavity & inner 2/3 cortex

describe periosteal capillaries

from soft tissue

supply outer 1/3 cortex

femur - linea aspera

describe metaphyseal/epiphyseal vessels

from periarticular tissues

Describe intramembranous ossification

sheets of mesenchymal connective tissue to osteoblasts

no cartilage model

flat bones

Describe endochondral ossification

mesenchymal stem cells to chondroblasts to BMU

uses cartilage model

long bones & secondary fracture healing

Stages/Zones of bone growth

(CLOSEST TO EPIPHYSIS)

1. Reserve: lots of matrix/type 2 collagen

2. Proliferation: bone lengthening

3. Hypertrophic: very little matrix, weakest part of physis, angiogenesis, collagen II to collagen X

4. Calcification: chondroclast degenerate cartilage/cells

5. Ossification: osteoblast form woven bone

(FARTHEST FROM EPIPHYSIS)

describe bone modeling

change shape and size in normal development

response to tension/compression

formation >> resorption on DIFFERENT surfaces

describe bone remodeling

renew bone

resorption then formation on SAME surface

ARRF (active, Resorp, Reverse, Form)

Describe Wolff's Law

rule of mechanical loading

+ load = - remodel = + formation = + bone mass

OR

- load = + remodel = - bone mass

microstructure of cortical bone

3-5% porosity = very dense

microstructure of cancellous bone

60-75% porosity

greater surface area

more metabolically active

describe periosteum

Outer = fibrous, support

Inner = cambrium, growth/healing

describe cortical bone remodeling

circular osteon w/blood vessels

dig tunnel then fill cortex

describe cancellous bone remodeling

hemiosteon without blood vessels

dig trench then fill surface

bone's response to injury

bleed, inflammation, cell death, cell proliferation, cell differentiation/replacement

goals of fracture fixation

1. optimize fracture healing potential (minimize strain, early weight baring, preserve blood supply, +/- bone graph)

2. restore anatomy

describe primary bone healing

direct

contact/gap heal

no callus

always used intra-articular fractures

describe secondary bone healing

indirect

heal with callous formation

when gap is >1mm

stronger, lesser infection, lesser surgical time

need smooth joint surface (NO intra-articular fracture)

what is delayed union

slow heal

what is Mal union

heal wrong

what is non union

not healed

fracture factors that affect healing

blood supply

age of fracture

previous healing issue

geography of fracture

strain (mechanical stability at fracture site)

host factors that affect healing

age

species

weight

activity level

infection

drugs

concurrent disease/condition

what is strain

strain (%) = motion/gap

<2-5% = primary heal

5-15% = endochondral ossification (need to decrease strain to progress cartilage to bone)

>15% = granulation tissue (nonunion if not addressed)