MSK Tissue Healing - Pt. 1

pt. 1!

contusion

______ is a bruise typically from sports where there is high compressive forces on a muscle

strain

______ is when the muscle tissue tears from the tendon or from itself

crush

_____ injury occurs when rhabdomyolysis is caused by too much of strenuous exercise

eccentric contractions

______ can also cause skeletal injuries

muscle strain

_____ is when the muscle fiber tears due to excessive mechanical stress

grade 1 muscle strain

_____ is when less than ½ of fibers are damaged and there is no change in ROM or strength

grade 2 muscle strain

______ is when about half of the fibers are damaged and there is edema and slight decrease in strength (d/t loss of ½ of fibers) and acute pain is present

grade 3 muscle strain

______ when there is a rupture of muscle and a total loss of function and severe pain

destruction

_______ is the 1st phase of muscle healing // rupture of sarcolemma/vasculature + formation of contraction band, necrosis triggers inflammatory phase (PMN leukocytes and macrophages), and inflammation occur

central (CZ), regenerating (RZ), and surviving (SZ)

______ are parts of demarcation of zones on day 2 of muscle healing

central zone

______ is where myofiber contraction creates a gap (with no basal lamina) and fills with a hematoma to ultimately create scar tissue in that region

regeneration zone

_____ is where the necrotic myofibers trigger the inflammatory response and preps for next cells while basal lamina remains there // this zone will ultimately become regenerated muscle fibers

surviving zone

_____ is where the undamaged myofibers fuse with other myofibers that are regenerated and covered with contraction band “cap” made up of ECM proteins // this zone ultimately fuses with regenerated myofibers in RZ

muscle repair phase

_____ occurs within regeneration zone where satellite cells proliferate (24 hrs post injury) and differentiate to myoblasts to fuse with myotubes and merge with SZ (days 2-7)

decreased

as age increases, satellite cells have a _____ capacity to regenerate to new myofibers

muscle repair phase

_____ occurs within central zone where there is removal of clots, angiogenesis and fibroplasia occur which lead to scar tissue formation (days 2-7)

late repair phase

______ involves contraction of scar tissue and regeneration of fibers merging into scar tissue as the ends come closer together (3 weeks post injury)

abjunctional stump

_____ is the end that does not contain a neuromuscular junction

-can’t contract and needs new nerves to grow

-use estim!

adjunctional stump

____ is the end that contains a neuromuscular junction

eccentric contraction

_____ occur from exercising too quickly with a large increase of weight too quickly

morphology

with eccentric contraction injuries, there is a change in muscle fiber _______ as the sarcolemma stays intact but the sarcomere structures become disorganized (z line shifts, widening of A bands, focal necrosis)

reduced strength regeneration

eccentric contraction injuries result in ______

repair process, muscle proteins

_____ for eccentric contraction injuries involves formation of ______ and reorganization within muscle fiber

less

for 2-3 weeks post eccentric contraction injury, muscle fiber diameter is typically _____ than prior to the injury

macrotrauma

____ is from high impact forces and the fx starts at areas of tensile load

microtrauma

_____ is similar to a “stress fx” and from repetitive overloading with rapid increase of activity where there is more damage than there is time to repair

simple fx

_____ doesn’t break through the skin

compound fx

______ breaks through the skin and is more prone to infections

greenstick fx

______ is more common in kids d/t the flexibility in bones - aka hairline fx

transverse fx

_____ is straight thru the bone

comminuted fx

_____ is when bone fx is multiple pieces and needs stabilization asap

spiral fx

_____ is from rotational forces

pathologic fx

______ occur under normal loading and is secondary to a bone pathology (osteoporosis, cancer, etc)

primary bone healing

______ is when bony ends are tightly opposed where minimal new tissue forms // surgical stabilization and compression - aka DIRECT

secondary bone healing

______ occurs when there is space and slight motion between bony ends that results in new tissue and forms a callus the extends the outside boundaries of the original bone - aka INDIRECT

reduced inflammatory phase

primary bone healing has a ______ and no soft callus or external hard callus

surgical fixation

primary bone healing occurs where there is minimal gap, minimal motion and is often where ______ occurs

gap healing, contact healing

primary bone healing is done via ______ and ______

gap method

_____ is when osteoblasts produce woven bone in fx gap which is later remodeled to lamellar bone via bone remodeling units

contact healing method

______ is the activation of bone remodeling units such as osteoclasts + cutting cones, osteoblasts + new osteoid, and angiogenesis in resorption canals - it is a DIRECT reconnection of bone

fixation devices, infections

____ are helpful in reducing displacements, early weight bearing, helping potential problems, and fixing abnormal stresses - help to reduce _______

hemostasis, inflammation, repair, modeling/remodeling

secondary bone healing has 4 stages: ______, _____, ______, and ______/______ and involves many chemical mediators

hemostasis

_______ occurs to stop the bleeding via vasoconstriction and platelet aggregation + coagulation - forms a hematoma around fx site

inflammation, chemical mediators

______ occurs when macrophages break down bacteria and clean up debris/necrotic tissue and releases __________ _______to guide inflammatory/repair processes

neutrophils, macrophages, osteoclasts

in the inflammatory stage, ________, ______, and ______ + WBCs enter the fx site to help with inflammatory process - usually peaks @ 48 hrs and resolves in a week or longer

reparative stage

_____ occurs within days of injury and angiogenesis occurs along with callus formation

-soft = cartilaginous (hyaline cartilage)

-hard = woven bone

soft callus formation

______ is made of hyaline cartilage and provides stability and scaffolding for endochondral bone formation and peaks after 1 week

cells: chondroblasts + fibroblasts

T

soft calluses are formed via migration and proliferation of mesenchymal cells. T/F

osteogenic, stem cells from bone marrow, adjacent cells

the mesenchymal cells that make up soft calluses are _______, ______, and _____ _____ like smooth muscle/satellite cells from skeletal muscle/fibroblasts

endochondral ossification

soft calluses transition to hard calluses after week 3/4 via _____ ______

hard calluses

________ form via endochondral bone formation from a hyaline cartilage model around week 3-4 with increased vascularity

proliferative zone

hard calluses have the same bone formation zones except ______

why: we don’t want the bones to get longer at this point, just heal the fx

modeling stage

_______ in bone healing restores the macrostructure of the bone while also removing the callus formed previously

remodeling stage, lamellar bone, osteoclasts, osteoblasts

_____ restores the microstructure and transitions it from woven bone to _______ while also restoring concurrent activity of _______ and _________ (bone multicellular units)

true

after the bone has gone through the 4 stages of healing it is restored to normal structure and function. T/F

F; slowly heals

delayed unions occur when the fx quickly heals after 3 months or longer. T/F

T

mal-unions are when the bones just aren’t aligning correctly and normal forces still aren’t working. T/F

F; same amount

non-unions are when there is a different amount of space compared to the original fx gap. T/F

risk factors

_____ of abnormal healing include older age, impaired vascular supply, # of comminuted fragments, systemic diseases (DM), malnutrition, meds (glucocorticoids), excess fx gap/displacement, motion at fx site, interposition of soft tissue, malignancy, infection

epiphyseal plate fxs

_______ often result in closure of the plate during the repair process - leg length discrepancies can occur in kids

-fx site will ossify and plate will close, bone stops growing