Skeletal Pathology Flashcards
3 steps to reducing a fracture are:
- ) Alignment
- ) Immobilization (internal vs. external)
- ) Preservation/Restoration
Why does a fracture hurt?
The periosteal membrane is highly innervated
List the steps of fracture healing in order:
- ) Hematoma formation
- ) Fibrocartilaginous (soft) callus
- ) Bony (hard) callus
- ) Remodeling
Hematoma formation occurs ___________ and is indicated by:
1 - 2 days following fracture;
Injured blood vessels and surrounding soft tissue turn into blood clot and new blood vessels develop/penetrate
The fibrocartilaginous callus forms within _________. It reaches max girth around ____________. This is good for stabilizing but not:
1 week
2 - 3 weeks
Bearing weight
What phase of fracture healing involves fibroblast and osteoblast migration?
The fibrocartilaginous callus
Some fibroblasts may become _________________ during the the fibrocartilaginous callus phase.
Chondrocytes
A bony callus is formed as ossification occurs during the _________________ week.
3rd and 4th
What do osteogenic cells do during the bony callus phase?
Become osteoblasts to lay down trabeculae
What is a “radiographic union” and in what phase does it occur?
When two pieces of bone fuse together.
During the bony callus phase
Remodeling can take 10-18 weeks for the average adult, but what factors could affect this?
- Health
- Nutriton
- Location
- Type of fracture
- Less SA (long bone) take longer to heal
What comes in during the remodeling phase that hasn’t appeared in any other phases thus far, and what does it do?
Osteoclasts. Resorption of any dead bone or overgrown bone to help re-establish medullary cavity and re-organize new bone
What type of bone is finally generated during the remodeling phase?
Compact bone!
Osteomyelitis is an acute or chronic (>6-8 weeks) infection of bone that has three origins… what are they?
Hematogenous - blood borne
Contiguous - Adjacent infection
Exogenous - direct trauma (including surgery!!)
Hematogenous osteomyelitis is not very common, but the most common way to contract it is through what bacteria in what population?
S. aureus in children or older/frail adults
Hematogenous osteomyelitis may form an ______________________ and is cured via:
Externally draining infection
Antibiotics, irrigation, and drainage (I and D)
What can lead to necrotic bone becoming trapped in a sinus in osteomyelitis (aka what leads to necrosis)?
Compression
What is a sequestrum?
A piece of trapped necrotic bone
What is a involucrum?
New reactive bone formed AROUND a sequestrum
Treatment for contiguous and exogenous osteomyelitis?
Antibiotic cement beads!
The pt. I had during mini clinical has ____________ osteomyelitis from a botched foot surgery so she had cement antibiotic beads placed in her foot.
Exogenous
Where is the most common site of infection for tuberculosis? And where is it spread from?
vertebrae and long bones of extremities, occasionally soft tissues and joints.
Spread from lungs or lymph nodes
What can bone destruction and abscess formation from tuberculosis lead to?
Deformities (kyphosis and scoliosis)
What is osteonecrosis and where is a common site in 10% of joint replacements?
Bone death due to ischemia as a result of fracture, thrombus, embolism, infection, compression/pressure.
Femoral head/neck
How do you treat osteonecrosis?
Immobilization, decreased weight bearing, joint replacement?
What is the difference between a primary and metastatic neoplasm of bone?
Primary = origin in bone
Metastatic = traveled from another tissue (cancers can metastasize to bone)
Both benign and malignant neoplasms of bone can be of concern because…
Growing of tissue can lead to fracture
Osteoma vs. Osteosarcoma:
Osteosarcoma is malignant
Most benign tumors are “osteochondromas”, these are…
An aberrant growth of lateral epiphyseal cartilage between cartilage and bone.
Commonly found in children
asymptomatic
Osteosarcoma is the most common primary cancer of bone with a _________ link and increased incidence in what population?
genetic link
adolescents
What increases risk of osteosarcoma?
Paget’s disease and radiation exposure
Signs and symptoms of osteosarcoma?
Deep local pain
night pain
presence of a mass
impairment of function
Treatment of osteosarcoma?
Amputation
Chemo
Ewing’s sarcoma is the second most common type of bone cancer in children/teens and is most common in which bones?
Long bones (especially femur)
Prognosis is poor if metastasis occurs
Benign and malignant tumors are both (primary/metastatic) bone disease:
Primary
Metastatic bone disease is (more/less) common than primary:
MORE
What types of cancers commonly metastasize to the bones:
Prostate, breast, and lung
What part of the skeleton is usually affected with metastatic bone disease?
Axial skeleton
(Hypocalcemia/hypercalcemia) is commonly related to metastatic bone disease:
HYPERcalcemia (loop diuretics to treat?)
Metabolic bone disease is an imbalance between:
Bone formation and resorption
What factors affect the equilibrium of bone formation/resorption?
- ) Mechanical stress
- ) Calcium/phosphate availability
- ) Hormones, cytokines, and vitamins
What turns over most each year: cortisol or trabecular bone?
Trabecular (25%)
What is osteopenia?
A decrease in bone mass greater than expected for certain age, race, and sex. (measured with DEXA scan)
What is type 1 osteoporosis?
- due to menopausal estrogen deficiency
- primary loss of trabecular bone
- greatest risk for vertebral and radial fracture
What is type 2 osteoporosis?
- a.k.a senile osteoporosis (occurs usually > 70 y.o.)
- also characterized by Ca+ deficiency
- cortical AND trabecular bone lost more slowly
- hip, long bone, and vertebral fractures
What is type 3 osteoporosis?
- Ca+ metabolism problems (could be via GI?)
- remember to treat underlying cause!
Can an older woman have both type 1 and type 2 osteoporosis?
YES! She is above 70 and lack of estrogen. Plus if she has Ca+ deficiency, forget about it!
Risk factors for osteoporosis:
- diet
- alcohol/nicotine/caffeine
- sedentary
- caucasian (even lighter skinned within race!)
- women who are estrogen deficient
- age
- small framed
Osteoporosis by itself only has one sign, but what else could happen to show it? (name both)
Loss of 2 inches in height
Low impact fracture (falling from standing height or less)
Treatment for osteoporosis?
- exercise and dietary changes
- supplements
- biophosphonates (inhibit osteoclasts)
- Selective estrogen receptor molecules (SERM’s)
