Midterm Review Flashcards
Modality
Application of some form of stress to the body for the purpose of eliciting an adaptive response
Phases of Healing: 1. Inflammatory Response Phase
- Chemical messengers elicit local and systemic effects, cells remove debris, and cells create groundwork for repair/regeneration
- Lasts 3-4 days
- Purpose: protect, localize and prepare for healing
Vasoconstriction
-Immediate response to injury: Norepinephrine limits blood loss
Vasodilation
- Occurs after Vasoconstriction due to the release of chemical mediators; Histamine and Leukotaxin
Cardinal Signs of Inflammation
- Heat
- Redness
- Swelling
- Pain
- Loss of function
WBCs and Inflammatory Response
Leukocytes:
- Margination = move to endothelial lining
- Pavementing= Line the endothelium in a tightly packed formation
- Chemotaxis = Drawn to injures site
- Phagocytosis begins
Clotting cascade
Permanent stop of blood loss from injure area
Fibrin patch
Fibrin forms the blood clot or scab over injured site
Phases of Healing: 2. Fibroblastic Repair
- Starts around 48-72 hrs after injury and may go on for 6 weeks
- 2 parts:
a. Granulation phase
b. Fibroblastic or proliferative phase
Fibroblastic Phase: a. Granulation
- Growth of new tissue(re-epithelialization)
- development of new blood vessels (angiogensis)
- development of fibrous tissue (Fibroplasia)
- Granulation tissue forms= connective tissue matrix
Fibroblastic Phase: b. Proliferation of fibroblasts
- accelerated laying down of collagen
- collagen matrix forms
Phases of Healing: 3.Maturation (remodeling phase)
- 3 weeks after injury
- Can last up to 2 years (majority 2 months)
- Granulation tissue replaced with Collagen fibers
- TYPE 3 collagen replaced with TYPE 1 collagen
Repair vs. Regeneration
Repair= tissues heal with a scar Regeneration = Actual tissue is replace (i.e. bone)
Fracture Healing: Phase I
Acute Phase: up to 1 week
- Hematoma forms= platelets (angiogensis)
- begins to develop fibrocartilage callus
Fracture Healing: Phase II
Repair/Regeration: up to 8-12 weeks
-Soft callus to hard callus: cartilage to bone occurs after week 3
Fracture Healing:
Phase III
Remodeling Phase: Resorption of callus
- as callus is removed trabecular bone lays down(may take years)
- Osteoblasts and Osteoclasts remodel the bone based on mechanical loading (Wolff’s Law)
Norepinephrine
causes Vasoconstriction; underlies “fight or flight” response
Enkephalins
Reduce pain perception by bonding to pain receptor sites
Endorphins
Morphine-like neurohormone; thought to increase pain threshold by bonding to pain receptor sites (generated by noxious stimuli)
Serotonin
Substance that causes local vasodilation and increase permeability of capillaries (generated by noxious stimuli)
Dorsal Nerve roots
Transmit:
- Sensory
- Afferent information
Ventral Nerve roots
Transmit:
- Motor
- Efferent information
Afferent Pathways: First order neuron
-connects to peripheral sensory receptor and projects info to DRG in SC. Synapses with cell body of second order neuron in DRG
Afferent Pathways: Second order neuron
cell body located in DRG
-crosses the midline and ascends to the thalamus