Fractures, Osteonecrosis, Osteomyelitis Flashcards
Stress fracture
Bone fractures after repeated stress
Incomplete fracture
Bone is not broken all the way across, still in one piece. The prototype is a Greenstick fracture which happens in young babies with fragile bones
Simple fracture
overlying tissues are intact
SImple complete
overlying tissues are intact and the bone is broken all the way across.
Compound fracture
bone has pierced the skin/ bacteria have a route to get into the body.
complex fracture
the opposite of simple…bones have done serious damage to overlying tissue
Pathologic fracture
fracture due to a force that would not break a normal bone
Where does osteonecrosis most commonly take place in the bone?
Convex surface of joints
What is the most feared result when bone tissue is dying near the convex surface of a joint?
detachment of the articular cartilage
What are the risk factors for osteonecrosis
- sickle cell disease
- decompression sickness: bubbles form clots, the bends in the bones
- Femoral neck fracture or dislocation
- Alcohol abuse- dont know why
- gluccocorticoid use- dont know why
One of the most common features of sickle cell crisis
is bone pain. Painful bone infarcts that can result in osteonecrosis
What is the normal cellularity in marrow?
50% cells and 50% fat
In sickle cell, bone marrow becomes hypercellular. Remember that bone marrow is generally 50% cells and 50% fat. In sickle cell it is almost 100% cells. This hypercellularity interferes with normal blood flow and can lead to infarct and necrosis
ok
Osteomyelitis
bone infection
Most frequent cause of osteomyelitis
pyogenic organisms. Develops by hematogenous spread or in pts with poor wound healing (vascular insufficiency).
Hematogenous osteomyelitis is most common in who?
Children 2-5 yo
Risk factors for osteomyelitis?
diabetes, orthopaedic surgery, adjacent infection, peripheral vascular disease, siclkle cell disease, congenital phagocytic function
Why is hematogenous osteomyelitis most common in 2-5 yo kids?
Because as long bones grow (remember they grow from the endochondral growth plate) they need heavy blood supply so infection is more likely to spread
Most cases of osteomyelitis are due to what type of bacteria
pus forming (pyogenic), more specificallly STAPH
Where does osteomyelitis generally begin in the bone?
Metaphysis (growth plate region)
In sickle cell disease, what type of bacteria often forms osteomyelitis
Salmonella…KNOW
What is Pott’s Disease
Tuberculosis osteomyelitis specifically in the vertebral column. Leads to collapse of the vertebral column .
Neonatal congenital syphillis
has one characteristic feature involving osteomyelitis of the nose and shins. Causes a saddle nose that is characteristic of congenital syphillis.
SCC and Osteomyelitis
YES> Squamous cell carcinoma can develop in the bone or sinus tract of ong standing osteomyelitis
Involucrum
sub periosteal shell of viable new bone surrounding the osteomyelitis. Forms outside of the destroyed bone…KNOW
Sequestrum
remaining fragment of necrotic cortical bone
Involucrum is commonly a cfeature of
osteomyelitis
Treponema Pallidum
Syphillis….a spirochete
Tertiary syphillis is characterized by the formation of what>
Gumma: soft, tumor-like granulomas. They are chronic and represent an inability of the immune system to clear the organism. Gummas produce a chronic inflammatory state and have mass-effects on the local anatomy.
Besides the gumma, what are other characteristics of unreated tertiary syphillis?
neuropathic joint disease, a degeneration of joint surfaces resulting from loss of sensation
Saber shin is a feature of
Congenital syphillis
What is saber shin
an anterior deformity of the tibia due to periostis and an inflammatory reaction at the outside of the bony cortex
