Basic Science Flashcards
Trends in orthopedics, whats increasing what is decreasing?
↓ Tuberculosis, polio, vitamin deficiencies
↓ Acute infections
↑ Arthritis, osteoporosis, fractures, MVA, sports injuries
↑ Statistics, evidence-based medicine, prevention, diagnostic imaging, arthroscopy, microsurgery
cancellous bone AKA
spongy bone
bones Storage reservoir for:
Ca, P, Mg. Na
Hemopoietic tissue.
bone, tissue that make blood cells
What type of loads bone withstand?
mechanical
cortical bone AKA
compact bone,
dense, surrounds cancellous
what is woven bone?
low mineral content, initial phase of fracture healing random collagen arrangement (not stress oriented)
weaker and more flexible than lamellar bone
this type of force result in frequent Fx in areas with more cancellous type of bone
shear forces
__________ forces are going cause fractures in pt with osteoporosis
Compresive forces
Weight bearing fracture
Wolff’s Law
- bone remodels in response to mechanical stress:
- stress = hypertrophy
- trabecular orientation follows stress pattern
what is the trabecular orientation
spongy bone, trabecular orientation follow stress pattern
trabecular orientation follows stress pattern acoording to which law?
Wolf’s law
2 types of bone growth:
endochondral (cartilaginous phase) or membranous bone growth
Embryo contains 3 cell layers:
- Ectoderm (covering)
- Mesoderm (middle) – mesenchyme (bone)
- Endoderm
Bone Balance development
(Bone deposition/resorption)
- Positive in childhood
- Neutral in adults
- Negative in elderly
Fracture healing process:
1 wk = hematoma (or immflamation)
2-3 wks = soft callous
4-16 wks = hard callous
17 wks & beyond = remodeling
Cartilage withstand what type of forces?
shear and compressive
Cartilage:
- Viscoelastic tissue
- Withstands shear and compressive forces
- Aneural, avascular
- Chondrocytes and intracellular substance
- Sponge-like behavior
tendons:
- transmit loads to bones
- attach muscle to bone
prevent excessive motion and guide joint motion
connect bone to bone
ligaments
1st degree sprain
ligament microfailure of fibers, minimal pain, no instability
2nd degree sprain
ligament partial rupture, strength decreases 50%, pain, some instability
3rd degree sprain:
almost complete rupture, intense pain during injury minimal after, severe instability
no end feel
true or false: Tendon mobilization prevents adhesions
Tendon mobilization prevents adhesions
true or false: Loading is necessary for optimal tissue health. When loading and the subsequent degradation of tolerance are followed by a period of rest, an adaptive tissue response increases tolerance. Tissue “training” result from the optimal blend of art and science in medicine and tissue biomechanics.
true
