Forces / Laws
You stretch a material but it does not return to its normal shape. What type of response is this?
plastic response
What is the good part of swelling and what is the bad part?
good part = brings in healing nutrients
bad part = clogs everything up
What are the advantages and disadvantages to dry healing?
disadvantages = heals slower, more scar
advantage = decreased risk of infection
What is the first bone that is created? What does it turn into?
woven bone
lamellar bone
Which fractures are most common in kids?
epiphyseal and greenstick
What is the SAID principle?
Specific adaptations to imposed demands
What are the 4 cardinal signs?
redness, heat, pain, swelling
Explain why tendons and ligaments do not heal as well.
They have lousy blood supply and no reparative cells on site.
What is tendonosis and how do you fix it?
Tendonosis is tendonitis that has lasted more than 6 weeks and has now turned the corner into degeneration of tissue. In order to fix tendonosis you need to create an inflammatory response to get the healing process to begin (scraping, cross friction massage). Eccentric exercises are also good for all tendonopathies.
What nutrients do you need for bone healing?
protein and vitamin C
What is a yield load?
max load a material can handle without deformation
Why does phase 3 (maturation and remodeling phase) take a year + to complete?
During this phase fibroblasts form collagen which is the building block for the body. Collagen is a triple helix structure that has to crosslink with disulfide bonds. It takes 1 full year to crosslink.
How does compression and elevation help healing?
They encourage venous outflow and lymphatic drainage through pressure (compression) or gravity (elevation).
What are the three phases of bone healing?
acute/inflammatory phase - formation of hematoma
proliferation phase - osteoclasts reabsorb damaged tissues; osteoblasts deposit near bone - enchondral vs direct healing
maturation phase - continued osteoclast and osteoblast activity - remodeling of bone
Why are sedentary and thin individuals more at risk for osteoporosis?
They are not enacting wolff's law. Sedentary people are not moving enough to create stresses on their bone which means their bones are not adapting & getting stronger. Thin people do not have large enough muscles to enact a big enough force on their bones for the bones to strengthen.
What is the difference between tension and shear?
Tension = axial force in opposite direction (think pulling)
Shear = force parallel to a plane passing through an object (think sliding/displacement)
Aspirin prevents platelets from sticking together. Platelets are the most important cell in phase 1 of physiotissue repair. If they can't form then phase 1 can't move into phase 2.
Ibuprofen binds with prostaglandin which results in the prostaglandin slowing down and reducing swelling. You need the initial amounts of swelling in order to bring in the healing nutrients.
Explain healing by primary intention and secondary intention and compare them to enchondral healing and direct healing in bone.
Primary intention = gaps in tissue that are less than 2 mm; minimal granulation material. This is similar to direct healing in bone. Direct healing is when the bones edges are pinned/immobilized together and they heal directly.
Secondary intention = gaps larger than 2mm; lots of granulation material and angiogenesis is performed. This is similar to enchondral bone healing which is when a callus is formed on the bone and remodels into lamellar bone.
You suspect your athlete has a stress fracture in her tibia. Would you refer her to a doctor for imaging why or why not?
No because the stress fracture likely will not show up on an x-ray until 3 weeks - once it starts healing.
What are the four phases of therapy? Briefly explain what happens in each phase.
1. control inflammation - RICE & break pain-spasm cycle
2. regain ROM - realign tissue - use arthrokinematics, proprioception (consider GLL vs keloider)
3. Regain strength, power, endurance - power & endurance are last - plyometrics
4. Return to function - sport specific & functional activities
Using Wolff's law explain why identical twins could have different bone structure/sizes.
Wolff's law states that for every external force on a bone there is a change in the internal architecture of the bone. So if twin A played football and twin B sat around and played video games all day then twin A would have thicker and stronger bones. Twin A is creating a lot of force through their bones when they play football. Their bones will adapt to that force and become stronger and thicker overtime.
In detail explain phase 1 of physiotissue repair.
Phase 1 is the acute/inflammatory phase. This phase lasts 48/72 hors - 0-6 days. The body's first response to an injury is vasoconstriction which can last seconds to 10 minutes. After that histamines trigger vasodilation which increases permeability allowing larger nutrients (plasma - protein - fibrin clot) to get through. Bradykinin is also released and can help trigger vasodilation, but the main job of bradykinin is to produce pain. With vasodilation reparative cells and platelets get out into the area resulting in exudate being formed. The next step is neutrophil infiltration which are your WBCs (infection fighters) coming on scene and starting phagocytosis. Next macrophages are stimulated by phagocytosis.
The most important cell in this phase are platelets!!
What are the 4 stages of tendonitis?
1: pain after activity only
2: pain during activity, does not restrict performance
3: pain during activity, restricts performance
4: chronic pain even at rest
What are the 3 grades of nerve injuries?
neuroplaxia = localized conduction block; resolves within days to a few weeks
axonotmesis = significant motor and mild sensory deficits; lasts 2 weeks
neurotmesis = motor and sensory deficit; lasts up to a year
How does the gate theory work?
You have two types of fibers: A and C. C fibers are what brings pain. These fibers are unmyelinated, small, and slow. A fibers bring other sensations and are myelinated, fast, and bigger. When you have pain, the gate to the C fibers is open while the gate to the A fibers is closed. In order to reduce pain you need to close the C gate by opening the A gate. Since A fibers are faster you can create other sensations by rubbing, tens unit, heat, analgesic balm and these will cause the C gate to close and reduce pain.