overview of MSK disease Flashcards
4 factors affecting healing in connective tissue
- proximity of viable tissue (apposition of damaged ends and removal of dead tissue)
- vascular supply (oxygen, nutrients, removing toxic byproducts)
- presence of infection
- physical/mechanical stress (including hormonal and metabolic macro and microenvironment)
degenerative joint disease is also called
osteoarthritis
2 crystal deposition diseases
gout and CPPD
sprain
stretch and/or tear of ligament
strain
stretch and/or tear of muscle or tendon
strain
stretch and/or tear of muscle or tendon
pathophysiology of soft tissue injury
disruption of collagen fibres and/or skeletal muscle cell
tendons and ligaments have poor blood supply and take sgnificant time to heal if torn
major gaps in soft tissue injury
healing cannot bridge major gaps
requires surgery and rehab
eg. achilles tendon tear, anterior cruciate ligament of knee
similar issues with incised wounds or lacerations involving tendons/muscle
fracture
a disruption in the cortex, trabecular bone or both
may lead to discontinuity in the bone
fracture occurs when
the stress or load on the bone exceeds the mechanical strength of the bone
avulsion
part of the bone is pulled off, for examplle by a tendon
classification for paediatric fractures involving the growth plate
salter-harris classification
classifcation for facial fractures
Le Fort
importance of fractures in paetiadric growth pllate
may impair normal future growth of the bone
integrated AO/JOT classification
- anatomical location
- fracture morphology - simple/wedge/multi-fragmentary/complex
- modifiers/qualfers (displacement/impaction/dislocation/articular/spiral)
most common types of fractures
- transverse
- linear (usually stress)
- oblique non-displaced
- oblique displaced
- spiral
- greenstick - on the side of the cortex
- comminuted
linear fracture is usually due to
stress
comminuted
multifragmentary
open fracture
commonly due to high energy trauma
tibia and phalanx of finger most common site
high risk of infection and necrotic bone and soft tissue or vascular compromise
fracture dislocation
high energy
often in hyperextended or hyperflexed position
risk of vascular compromise
often may have avulsion or intra-articular components or secondary injury
crush fracture
type of impaction fracture
particularly involving vertebral body of spine, can be very severe pain and neural/functional issues
often insufficiency fracture
pathological and insufficiency fractures
low trauma
fracture due to normal stress on abnormal bone that occur in the setting of either no history of trauma, or a low energy injury that ordinarily would not cause a fracture
pathological fracture
fracture through a pre existing lesion in the bone
insufficiency fracture
type of pathological fracture where the entire bone is weakened.abnormal (osteoporosis, paget’s)
repetitive injury/stress fracture
accumulation of micro-fractures leading to a true fracture of the cortex
abnormal stress on normal bone
compression fracture
due to abnormal end on load
non-accidental injury
suspected physical abuse.inflicted injury
multiple fractures, different angles
different ages of fractures
fractures in sites not normally injured
history is inconsistent with the severity or pattern of injury
model of fracture healing
- bleeding followed by haematoma (blood clot)
- inflammatory stage - leading to granulation tissue (new vessel formation) and organisation of the haematoma over several days
- soft calllus - fibrin meshwork, fibroblast ingrowth
- activated mesenchymal cells differentiate into chrondrocytes that produce firbocartilage and hyaline cartilage
- undergo enchondral ossification
- leads to bony callus
- over weeks to months the bony callus undergoes remodelling and progressively returns to pre-fracture strength
- signs of old fracture can persist for years and remodelling continues
four main factors affecting healing
- immobilization - aposition of damaged ends
- vascular supply - oxygen, nutrients, removing toxic byproducts)
- presence of infection
- physical/mechanical stress (including hormonal and metabolic macro and microenvironment
early fracture complications
- bleeding and complications of major haemorrhage
- infection and sepsis
- hypoxia/ischaemia and other tissues in vascular territory
- inability to bear weight/mobilise
- disproportionate strain
intermediate - late complications
- pulmonary embolism (thrombus, fat/marrow embolus)
- compartment syndrome - can cause vascular or nerve compromise
- joint problems (intra-articular), spontaneous arthrodesis, early OA
- chronic osteomyelitis
non-union
fracture site does not heal
causes of non-union
interposition of soft tissue excessuce gap or step infection poor blood supply malignancy - local or systemc malnutrition/metabolic disease (diabetes, cushing's, vit C definiency)
pseudoarthritis
false joint
deformity oof bone, secndary mechanical effects due to altered force on the joint, refracture
