A3 Bone grafts, open fractures and external skeletal fixation Flashcards
Become familiar with the basic techniques of fracture reduction, know the principles and basic component of external skeletal fixation, understand the principle of bone grafting, have a basic understanding how to deal with an open fracture
What are the 4 As of assessing radiographs?
Alignment
Apposition
Apparatus
Activity
What are the 3 Os of cancellous bone grafts?
Osteogenesis
Osteoinduction
Osteoconduction
- What type of dressing should we use prior to bandaging in an open fracture? Why?
- Before applying a dressing and bandage, what is important to do?
- Wet to dry dressing. It helps in superficial debridement.
2. Clipp, clean and debride!
Name six examples of situations when the cortical bone graft can be considered.
- Treatment of multifragment diaphyseal long-bone fractures.
- Management of malunion / non-union fractures.
- Limb salvage procedures for primary bone tumours.
- Limb lengthening procedures.
- Graft in vertebral fusion - wobblers.
- Arthrodesis in combination with serious bone loss.
- What are the two types of threaded pins?
2. Which one is stronger and why?
- Positive and negative profiled pins
- Positive profiled pin is stronger, because the threads sit onto the outside of the pin, that means the core diameter of the pin remains the same throughout the treaded and non-threaded portions.
What are the advantages of using a carbon fibre rod in ESF?
They are lightweight and you can see through them on radiographs.
Name six uses of a cancellous bone graft (CBG)?
- To stimulate bony union in fracture repair
- To fill bone cysts
- Arthrodeses
- Delayed or non union fractures
- Treatment of osteomyelitis
- Enhancement of vascularisation of cortical grafts
What are the different grades of open fractures? Explain how they are defined.
Grade I - small puncture wound caused by a bone end penetrating skin from the inside out, without skin loss
Grade II - large skin wound caused by external trauma with loss of skin
Grade III - extensive skin and soft tissue damage, often associated with severe comminuted fractures and risks of complications high
When would you use closed fracture reduction?
Recent fractures
Stable fractures
Lower limb fractures (less soft tissue so easier to reduce and palpate)
What six methods can assist closed reduction?
- Traction
- Counter-traction
- Manipulation
- Bending
- Using the animal’s weight to reduce the fracture (hoist fractured limb of anaesthetised animal to a drip stand for 10-30 minutes prior to fracture reduction)
What is a circular ESF especially suitable for?
- small bones or very small fracture fragments close to joint
- limb lengthening procedures
- correction of angular limb deformities
(can also be used for regular fx fixaton, but there are more straight forward methods available)
What are the two forms of clamps used for in a linear ESF?
Double clamp - joining two connecting rods
Single clamp - attaches pin to connecting rod
What are the limitations which mean cortical bone grafts are rarely used?
- In cortical autographs the is a limit to how much bone can be taken before you compromise the donor site.
- In cortical allographs bone is obtained by euthanising a healthy donor
- There is no osteogenesis as viable cells are rejected
- Cortical grafts are revascularised much more slowly than cancellous grafts
- The strength gradually declines due to osteoclastic resorption
- Cortical grafts remain as mixtures of necrotic and viable bone so do not fully incorporate.
What priority is an open fracture, how would you care for it?
EMERGENCY!
- Haemostasis
- Cover wound with a sterile dressing whilst preparing for lavage
- Wear sterile gloves, hat, mask and gown
- Apply water soluble gel or saline soaked swabs to the wound
- Clip away hair, working from the wound outwards if possible to reduce contamination
- Flush wound with a large amount of of sterile saline to remove debris & dilute bacteria
- Take a deep bacterial swab for culture (very important!)
- Apply a sterile dressing & bandage
