Unit 2 Phases of Healing Flashcards
what are the four phases of healing?
hemostasis, inflammation, proliferation, and remodeling
how do MSK injuries usually occur?
typically with a mechanical force.
direct trauma, compression, friction, repeated over-stretching
The response to injury occurs ___ and ___.
sequentially and simultaneously
why is it important to understand the phases of healing?
to make sound judgement in pt care and know the appropriate timing for interventions
optimize function in long term
what is primary healing?
occurring due to the injury/insult to the tissue itself
what is secondary healing?
response to the damage that is done by the healing process (inflammation)
T/F: the healing phases do not overlap.
false. there is a substantial amount of overlap
When discussing MSK injuries which pathway from the inflammatory phase do we follow? CNS or Non-CNS?
Non-CNS
what is the length of hemostasis?
0 to up to 6-8 hours. occurs immediately after the injury if bleeding occurs until bleeding stops
what is the purpose of the hemostasis phase?
stop the bleeding
Describe the cellular and vascular cascade.
- local vasoconstriction
- clot formation via simulation of platelets and formation of fibrin
- cells (fibroblasts) drawn to the area by growth factors to repair ECM
what is the length of the inflammatory phase?
0 hours to up to 2 weeks. begins at the point of injury as soon as chemical mediators start to move.
when does the inflammatory phase peak?
2-3 hours
what is the purpose of the inflammatory phase?
clean up the wound site and prepare for construction
what are the prominent inflammatory mediators?
histamine, bradykinin, serotonin, lymphokines, prostaglandins, leukotrienes, arachidonic acid
what is the difference between cytoprotective prostaglandins and inflammatory prostaglandins?
cytoprotective: activated by COX-1. normal homeostatic needed for normal body function
inflammatory: activated by COX-2. with injury. start of the inflammatory response
what inhibits COX-1 and COX-2 from activating prostaglandins?
both: non-selective NSAIDS and Aspirin
COX-2: selective NSAIDS
what is the inflammatory response? what is occuring?
chemical mediators (PGS, histamine, leukotrienes and kinins) cause vasodilation of local blood vessels and inc’d cap permeability which allows intravascular fluid, protein, and cellular components into extravascular space (leads to edema) and circulating cells and chemical mediators to the injured tissue
what is diapedesis?
when circulating cells and chemical mediators squeeze through gaps in the capillary walls to get where they need to go (injured tissue)
what is chemotaxis?
when circulating cells and chemical mediators are signaled by chemical agents in the area of the injured tissue
what do cells like neutrophils, macrophages, lymphocytes and mast cells do during the inflammatory response? and what are the two ways?
remove/eliminate injurious stimulus.
1. enzymes/toxic substances kill, inactivate and degrade microbial agents or necrotic tissue
2. phagocytosis (clean up work, taking up dead cells) and release of growth factor (neutro and macro)
what are the clinical signs of the inflammatory response?
redness (rubor), increased temp (calor), swelling (tumor), pain (dolor) and function loss (functio laesa)
potential for muscle guarding, self-splinting, protective posturing.
with passive movement pain is reported before tissue resistance is reached (empty end feel)
The inflammatory phase continues until it resolves. what is the resolution of the inflammatory phase?
- neutrophil apoptosis (die), as they die they trigger more inflammation and more WBC influx
- macrophages gobble up dying cells and stop the noxious stuff leaking from them
- macrophages then switch jobs and secrete an anti-inflammatory cytokine and suppress the release of pro-inflammatory mediators. they help regenerate tissue, or they leave.
how no NSAIDS affect the inflammatory phase?
can delay or hamper healing in MSK tissues including muscle, tendons, cartilage, and bone. inflammation is a necessary step for healing and transition to proliferation
how can repetitive or forceful tasks affect the inflammatory phase?
can cause the acute inflammatory stage to continue, followed by fibrotic and structural tissue changes (possibly CNS reorganization resulting in movement disorders)