Introduction Flashcards
complete or incomplete disruption in continuity and structure of bone and cartilage
fracture
fracture creates insult to what 3 things
bone marrow, periosteum, soft tissues
bone is ___ and withstands varying mechanical forces differently
anisotropic - meaning unequal in length
*
cortical bone is stronger on ___ forces
cortical bone is less resilient to ___ forces
cortical bone is most vulnerable to ____ forces
stronger on compression
less resilient on distraction
vulnerable to shearing
fracture occurs involving what 3 forces? is one more dominant than the others?
compression, distraction, shearing
yes, one predominates
trauma is absorbed by what before they fail to provide support resulting in injury
muscles and ligaments
*
fracture always involves varying but significant ___ damage
soft tissue
repeated loading of muscles and bones results in __ which would lead to fracture more easily
fatigue
surgical pin holes or sight of bone resection weakens the bone forming what
stress raiser
incomplete fractures are most common seen in what people
children
what are the 3 different types of incomplete fractures
torus - cortical buckling on compression
green stick - incomplete fracture on tension
plastic deformity - bending of bone without angular break or remodeling
what are the 3 different types of complete fractures
transverse
oblique
spiral
fractured fragment of bone being detached by the tension from muscles or ligaments
avulsion fracture
corner fracture that is chipped rather than avulsed
chip fracture
fracture that results in telescoping of osseous trabeculae
no radiolucent lines are seen but instead there is zone of sclerosis or condensation
impaction or compression fracture
fracture found in the calvaria/cranial vault or tibial plateau
depression fracture
fracture caused by repeated stress to normal bone leading to bone marrow hyperemia and bone resorption
fatigue or stress fracture
where do stress fractures most often occur? and what is the name of each?
march fracture - 2nd or 3rd MT stress fracture
runners fracture - tibial stress fracture
fracture caused by normal stresses to bone such as weight bearing or walking movements applied to osteoporotic or involuted bone
insufficiency fracture
where do insufficiency fractures occur
osteroportic vertebral bodies or sacrum
fracture caused by weakened bone due to neoplasm, infection, or collagen defect
pathological fracture
what is a fracture called with more than 2 segments
comminuted fracture
what are the 2 types of comminuted fracture
segmental fracture - 2 separate fracture lines producing an isolated segment
butterfly fragment - wedge shaped fragment produced at apex of the maximum force *
which fracture may is very complex in any bone resulting in instability along with neuro and vascular complications
comminuted
many comminuted fractures require what for treatment
surgical fixation
a simple cast will not due
what fractures are most commonly seen in flat bones
depressed fracture
when skin is intact and no communication with the outside air is present, the fracture is considered ____
closed fracture
when skin is punctured and communication with the outside air is present, the fracture is considered ____
open fracture
stating the relative position of fractures is based on what?
region of bone (met, di, epiphysis) affected by the fracture
super important to distinguish what region of bone is affected!
if the fracture extends into the joint it is called?
what are the complications?
intra-articular fracture
complications - delayed healing, abnormal healing, chondrolysis, secondary OA
what does apposition mean
displaced either anterior, posterior, lateral, or medial
when bone ends are not aligned we say they have loss of what?
loss of apposition
what are the varying types of apposition
bayonet apposition - overlap of one fragment over another
distraction apposition - complete loss of apposition due to traction forces
alignment apposition - valgus (away from midline) and varus (towards midline) bone alignment relative to distal fragment *
what classification method is used for pediatric growth plate injury
salter harris classification
what are the most vulnerable regions for fracture in the pediatric skeleton?
why?
epiphyseal growth plate and growth apophysis are most vulnerable in pediatric skeleton
because they of there cartilaginous nature and metabolic activity
how many salter harris classifications are there? how many do we talk about?
9 total
5 main types that we discuss in class
salter harris __ - fracture through growth plate itself that is often unrecognized because of minimal displacement
salter harris type 1
most common salter harris fracture >75%
salter harris type 2
salter harris __ - fracture through physis and metaphysis / metaphyseal corner forming a thurston holland fragment
salter harris type 2
which salter harris fracture forms a thurston holland fragment
salter harris type 2
salter harris type __ - fracture through epiphyseal plate and into epiphysis resulting in intra-articular extension
salter harris type 3
salter harris type __ - fracture that transverses metaphysis, physis, and into epiphysis
salter harris type 4
salter harris type __ - crush injury to growth plate often unrecognized or confused with type 1 fracture but causes damage to the physeal blood supply
salter harris type 5
what two salter harris fractures show the highest complications?
what may these lead to?
salter harris type 4 and 5
leads to premature plate closure, limb deformities, and limb shortening
which salter harris fracture has good healing prospects
salter harris type 2
which two salter harris fractures may go unnoticed and unrecognized?
type 1 and type 5
except type 5 has much worse prognosis can lead to premature plate closure
subtype of insufficiency fracture that develops in bones with insufficient osteoid
pseudo-fracture
pseudo fractures are most commonly seen in patients with what disease
rickets and osteomalacia
others but not as common include hyperparathyroidism, renal osteodystrophy, and paget disease
what is a pseudo-fractures characteristic appearance on xrays
widened transverse radiolucent lines oriented at right angles that are medial to the cortex of long bones *
pseudo-fractures are often referred to as what
looser zones
milkman lines
umbau zones
intraosseous edema found in bone during injury is called a
bone bruise
what is the best way to detect a bone bruise on imaging
MRI
pain in snuff box and FOOSH injury should require repeat xray after how many days?
7 days
occult scaphoid fracture may be diagnosis
what type of fracture occurs in bones due to mismatch of bone strength and chronic mechanical forces placed upon the bone
stress fracture
abnormal stresses on normal bone results in _____
normal stresses on abnormal bone results in _____
fatigue fracture
insufficiency fracture
what is it called when there is complete loss of articular contact or alignment as a result of injury of periarticular restraints
dislocation
what is it called when there is partial loss of articular alignment
subluxation
what is it called when there is separation of fibrous joints
diastasis
where do diastasis most often occur
suture diastasis in skull
pubic symphysis diastasis
anterior dislocation of a joint refers to what being displaced anteriorly
the proximal bone
growing skull fracture is also called
leptiomeningeal cyst
NOT A TRUE CYST
when does a leptomeningeal cyst or growing skull fracture develop?
how does this happen?
develops prior to closure of skull sutures < 3 years old
results from tear in dura mater followed by leptomeningeal and brain herniation with CSF pulsations - NOT A TRUE CYST
traumatic disruption of bone and periosteum causes significant hemorrhage that initiates what process
fracture healing
what are the 3 phases of fracture healing
inflammatory - first 48 hours
- hematoma and inflammatory cells initiate chemotaxis which brings phagocytes and repair cells to location of injury
repair - 7-14 days
- cells involved in inflammation gradually form granulation tissue while also removing unwanted tissue
remodeling - 9-24 months
- cells evolve into fibroblasts, chondrocytes, and osteoblasts forming new bone mineralization
what are the requirements for fracture healing
- good fragment apposition and normal blood supply
- immobilization with adequate physiological stress
- absence of infection
- absence of systemic factors complicating good health and healing
which is the shortest phase of fracture healing
inflammatory phase - first 48 hours
during what phase of fracture healing does the hematoma become vascularized and appears more translucent on xrays
repair phase - 7-14 days
during the repair phase of fracture healing, the fracture callus is very vulnerable to __ forces but may be stimulated to grow and develop faster if limited __ forces are applied
vulnerable to shearing forces
stimulated by axial forces
when does fracture callus formation occur
repair phase - 7-14 days
due to vascularity of the periosteum, ___ fractures heal quicker
pediatric
what are the 3 types of disturbances seen in fracture healing
delayed union - takes twice as long unionized
non union - no healing greater than 9 months - also called psuedoarthrosis
malunion - healing occurred in abnormal position
what are the 3 types of non union disturbances in fracture healing
hypertrophic - abnormal exuberant callus
hypotrophic - weak callus with insufficient vascularization and new bone formation
atrophic - absent callus with synovial fluid or infected exudate between fracture ends
what are the major complications of fractures
immediate - neuro and blood supply, acute compartment syndrome, renal failure, pulmonary fat embolism, gas gangrene
intermediate - osteomyelitis, sepsis, complex regional pain syndrome, RSDS, non union or malunion
late - ischemic necrosis, AVN, secondary OA
gun shot wounds - may lead to lead toxicity (if bullet lodged in synovial or serous cavity it will be degraded by hyaluronic acid leading to lead being released into the system)
