Bone injury and healing Flashcards
(35 cards)
what are the different mechanisms of action that can lead to bone fracture?
Trauma- Low or HIgh energy
Stress- abnormal stress on normal bone
Pathological- normal stress on abnormal bone
what are the different types of fracture?

what type of fracture is it if the bony ends arent aligned?
displaced
what are the questions you ask yourself when trying to figure out what type of fracture it is?
- are the soft tissues intact?
- is the break complete? if so how many pieces
- are the bony ends aligned?
Whats the difference between high energy and low energy trauma?
High energy- car crash
Low energy- simple fall
Describe how abnormal stress on bone can lead to fracture
- Overuse
- stress exerted is GREATER than bone capacity to remodel
- Bone weakens
- Stress fracture
- Risk of complete fracture increases
what are the types of bone typically affected by abnormal stresses?
Weight bearing bones like:
Tibia, Metatarsals, navicular
what are the related activities that can lead to abnormal stresses on bone
Athletes, military, femal athlete triad

In pathological mechanisms, what are the common pathologies and what can they lead to?
- Osteoporosis- soft bone
- Malignancy- caused by bone metastases or primary
- Vit D deficiency- rickets or osteomalacia
- Osteomylitis
- Osteogenesis imperfecta
- Paget’s disease
what are the 2 different types of bone metastases malignancy; give examples
BLASTIC- Prostrate and breast; increase in size
LYTIC; decrease in size by breaking down- Breast, kidney, thyroid, lung
what are the examples of primary bone cancers?
Osteosarcoma
Chondrosarcoma
Ewing sarcoma
Chordoma
Contrastthe effects of Vit D def on kids and adults, explain why
kiDS: cause RICKETS- bowing of legs. this is due to deficeny before epiphyseal plate closes
ADULTS: Osteomalacia; physis has already closed. No deformity seen but bone is soft and can EASILY fracture
Describe the pathophysiology of Osteogenesis imperfecta
decreased Type 1 collagen secretion OR abnormal collagen secretion
insuffucient osteiod production
effects:
- Blue sclera
- heart, and hearing problems.Bone problem
How does Paget’s disease develop?
caused by GENETIC AND ACQUIRED factors
XS bone breakdown and disorganised remodelling. Lead to deformity, pain, fracture or arthritis
May develop into a malignant disease

what are the four stages of Pagets disease
- Osteoclastic activity
- Mixed osteo-osteoblast activity
- osteoblastic activity
- malognant degeneration
what are the different stages of fracture healing?
- Heamatoma, release of cytokines and granulation tissue
- Week2-4 soft callus (type 2 collagen) and then gets turned to hard callus (type1)
- 4-12 months; bone remodels to external activityand forces. excess bone is removed

What is Wolff’s law
bone remodels and grows in responseto forces placed on it
what is primary bone healing?
Intermembranous healing; osteocytes easily jump across gaps
absolute stability

What is secondary bone healing?
Endochondral healing
involves responses in periosteum and external soft tissues
Relative stabiltiy

what is normal fracture helaing time
3-12 weeks depending on site.
it takes longer the further it is from the heart.
healing signs seen on X rays from 7-10 days
what are the 3 steps in effective fracture mangement?
Reduce
Hold or fix
Rehabilitate
what are the different ways of reduction?

what are the different ways of holding

what are the different ways of fixation



