Principles of Fracture Treatment Flashcards
Are more fractures due to direct trauma or indirect trauma?
Indirect
What are some examples of indirect trauma causing fractures?
Twisting or bending forces
Very low energy fractures are usually due to what?
An underlying weakness of bone, pathological fracture
What provides the shock absorption for the ends of long bones?
Spongey bone
Describe primary bone healing?
This occurs when there is a minimal fracture gap (< 1mm) which will be filled in with new bone by osteoblasts
Give some examples of when primary bone healing would occur?
Hairline fractures, following fixation with plates/screws
Once a substantial fracture has occurred, secondary bone healing will need to take place. What is the first thing that will happen after the fracture?
There is inflammation of the damaged tissue forming a haematoma
Following the formation of a haematoma, what are the functions of macrophages and osteoclasts?
Macrophages remove debris, and osteoclasts resorb the bone ends
What is the next step in secondary bone healing, following the actions of macrophages and osteoclasts?
Granulation tissue forms from fibroblasts and new blood vessels form
Following the laying down of granulation tissue in secondary bone healing, what then forms the soft callus?
Chondrocytes laying down cartilage
After the soft callus is formed in secondary bone healing, endochondral ossification takes place. What is this?
Osteoblasts lay down new bone matrix
What forms the hard callus in secondary bone healing?
Calcium mineralisation
What is the last stage of secondary bone healing?
Remodelling
Give some examples of when secondary bone healing would occur?
Colles fracture, IM nail, external fixation
When you look at an x-ray of a healing fracture, what is it that can be seen?
The hard callus of calcified bone
In terms of the timescale of secondary bone healing- when do both the soft and hard callus’ form?
Soft = 2-3 weeks, hard = 6-12 weeks
What things must there be, for secondary bone healing to be successful?
Good blood supply for oxygen and nutrients, stem cells, the ability of a little movement
If a fracture is trying to heal with secondary healing but there is a lack of blood supply, no movement, too big a fracture gap or tissue trapped in the fracture gap, what can this result in?
Atrophic non-union
What are some factors which negatively impact fracture healing?
Smoking, chronic ill health, malnutrition, vascular diseases
What causes hypertrophic non-union?
Inadequate immobilisation with adequate blood supply
What causes atrophic non-union?
Inadequate immobilisation with inadequate blood supply
In which type of non-union is there lots of hard callus formation but too much movement to bridge the gap?
Hypertrophic
What investigation is the gold standard in assessment of fractures?
X-ray
What investigation can be used to assess awkward bones?
CT
