introduction Flashcards
2 factors determining injury
- magnitude of force
- material properties of tissues involved
stress strain curve
for ligaments and tendons
elastic region: normal function w/o injury
plastic region: ligs/tens have inc risk of partial tear or rupture depending on tissue type
rupture point: complete tear
factors of force
- magnitude
- size
- direction of force: jt anatomy determines vulnerability
- position of a limb/jt when stress is applied
- AREA over which load is applied…dispersion - material properties
- ability of tissue to withstand strain
- musc vs bone
tension vs shear
bending vs torsion
tension: stretch apart
shear: combination of compression and tension
bending: tension on one side, compression on other
torsion: twisting along longitudinal axis
torque
depends on amount of force prod by muscle, and how FAR the muscle if from the origin
torque = force x moment arm
moment arm = perpendicular distance from force line to axis of rotation
components of soft tissue
elastin: provides elasticity
collagen: mainly makes up skin, tendons, ligs
- some stretch, mainly inelastic
- strong in resisting tensile forces
skin
dermis: has multidirectional force resistance
- arrangement makes resistant to shear, compression, tension
fibre types: elastin, collagen, reticular
injuries i.e. abrasion, laceration, burn, blister
main concern is INFECTION
aniostropic
different response to loads from diff directions
many tissues are aniostropic
systematic infection
spreads to other body parts, results in fever
aponeuroses
connective tissues that connect muscle to other muscle or bone
flat, sheetlike
injury i.e. plantar fasciitis
MOI = overuse
tendons
connect muscle to bone, are contractile
high collagen, low elastin
parallel fibre alignment allows unidirectional tension load
- 2x stronger than muscle
viscoelastic
muscle is viscoelastic
time dependent elasticity….sustained force will result in inc musc stretch
contusion
MOI = compression
S&S = bruising, acute onset, restricted ROM, swelling, nerve compression
ROM severity rating:
- 1st deg = mild/no restriction
- 2nd = noticeable
- 3rd = severe restriction
concern is secondary complications:
- compartment syndrome
- myositis ossificans
sequelae
secondary complications, other body areas impacted by injury
myositis ossificans
palpable lump, most common in quads
primary cause = repeated injury before healed
- can also be bcs of aggressive treatment in early healing
signs: light inc temp, pain after 1-2 treatments
detect via xray
risk factors: increased blood flow
- exercise
- heat
- massage
- severity and location of contusion
strain
macrotrauma affecting muscle or tendon…usually indirect tensile forces
causes tearing of tissue and hemorrhage
MOI = acceleration, fatigue, weakness, instability
S&S = pain, sounds, colour
- tender, swelling, divot in tissue
- dec function and ROM, STRENGTH CHANGES
classification:
- 1st deg = few fibres torn, mild weak/loss function/defect/pain/ROM
- 2nd deg = nearly half torn, moderate
- 3rd deg = all fibres torn, severe (may not feel pain bcs detachment)
what tissue tears first
muscle, because tendons are 2x stronger
joint capsule
membrane enclosing jt, mostly collagen
fibrous connective tissue around synovial joint
holds bone in place, protects synovial membrane
synovial membrane: inner lining, secretes synovial fluid which gives nutrients and waste disposal
ligaments
connect bone to bone
- collagen is parallel and interwoven, some elastin mixed
- can resist large tensile load along long axis (dec load other directions)
IDed according to:
- shape
- arranement w other ligs
- relation to jt
- function
- bony attachment
sprain
joint injury, stretch or tear of LIGAMENT
MOI = tension, acute
S&S = SHARP, instability
SHARP
helps ID signs of inflammation
swelling
heat: bcs inc BF
altered function
redness
pain
benefits of inflammation
vital part of immune system’s resp to injury/infection
prostaglandins: create blood clots
clears necrotic cells and damaged tissues
nutrition to tissues and initiates repari
dislocation and subluxation
dislocation = complete disarticulation of jt
subluxation = incomplete or partial dislocation of jt
MOI = tension
S&S = loss of limb function, deformity, swelling, pt tenderness
sequelae = reoccurance bcs overstretched capsule, instability
don’t “put” jt back in bcs could cause fracture, overstretching
- needs xray
bursa
not rlly fluid filled sac, bt flat
- dec friction
- protect tendons from bony prominences
bursitis
inflammation of bursa, can be acute or chronic
septic vs aseptic
MOI = compression
S&S = aching/burning, disability, heat, crepitus
- rebound pain: hurts when let go of squeezing
parts of bone
diaphysis = shaft
epiphysis = articulating ends
metaphysis = neck b/w epi and dia
periosteum = covering of bone
- periostitis when musc attachments pull on covering, making inflamed `
fractures
MOI = sudden injury i.e. fall, crush
- can also be fatigue in overuse
- usually break at weakest point w small diameter and vulnerability
- or break at tendon/lig insertions bcs inc stress
S&S = pain, swelling, GUARDING, spasm, crepitus, loss of power
types of fractures
stress = chronic, aka incomplete fracture
- weakness rather than thru bone
depressed = dent, more often w flat bones i.e. skull, bone driven inwards
transverse = straight line across
comminuated = several pieces
oblique = diagonal break, when torsion occurs when one end is fixed
greenstick = incomplete, inc in kids bcs bones less likely to break
impacted = bone driven into other bone, compression
avulsion = lig or tendon pulls off bone
spiral = s-shaped, torsion applied to fixed bone
apophyseal injury
injuries to bone region where a tendon attaches
- often young athletes
- as athlete grows, tension of apophysis causes EXCESSIVE GROWTH i.e. bump below knee
treatment is self-limiting, dec intensity
self-resolving
epiphyseal fracture
separation of epiphysis, growth plate injury
determined via SALTER-HARRIS classification
SALTER-HARRIS fractures
inc in severity as go down list, likelihood of impacting growth
Separated: space b/w growth plate widens
Above: fracture above growth plate
Lower: below plate
Through and through: travels thru metaphysis and epiphysis
Rammed: epiphyses rammed against e/o (crush)
