Fractures Flashcards
What is the definition of a fracture?
A complete or incomplete break in the continuity of bone and/ or cartilage
What are bone fractures usually accompanied by?
- Variable degree of soft tissue injury
- Locomotor dysfunction
- Maybe accompanied by significant injury to other body systems
What three aspects does the osseous blood supply have?
Afferent
Intermediate
Efferent
Describe the afferent blood supply of the bone…
- Principal nutrient artery
- Metaphyseal and Periosteal arteries are in association with muscle attachments
- Epiphyseal arteries separate the blood supply from the metaphysis
Describe the intermediate blood supply of the bone…
Fine system of little tiny vessels that run through the bone
Describe the Efferent blood supply of the bone…
Venous drainage at the periosteal surface
Where does the inside 2/3 of the bone get all of its blood supply from?
From the interior of the bone
In most significant injuries, which artery is damaged?
The Nutrient artery
- Less important than other vessels
What is the Secondary Bone healing sequence…
- Haemorrhage & clot formation
- Inflammation & Oedema
- Proliferation of cells
- Cartilage & Bone formation (callus)
- Remodelling
What are the two types of fracture healing?
Primary
Secondary
Describe Primary Bone Healing…
Direct production of new bone with no precursor
- No callus
- Requires perfect anatomical reduction and rigid fixation
- Osteoblasts lay new lamellar bone if theres a gap
- Plates take the weight and load share with the bone
What is a bone callus?
When the body creates a whole lot of extra bone
- Stabilises the fragments to allow lamellar bone to grow and fill the fracture gap
- Size of callus is related to the stability of the fracture - more callus= less stable
- Not good within or around a joint - need primary healing here without callus production
- Initially stronger than primary
- Three types of callus
What do osteoblasts do in primary bone healing?
If there is a gap between bone, osteoblasts will lay lamellar bone perpendicular to the long axis followed by cutting cores
Describe the fracture vascular supply…
Afferent artery hypertrophies
Extraosseous vessels are the most important in repair.
What is the most important blood supply in fracture repair?
Extraosseous blood supply
What is the most important thing about fracture repair?
Preserving the blood supply!
Vascular response is imperative!
What will affects the vascular response to a fracture?
- Nature of the Trauma
- Surgical Handling
- Inadequate reduction
- Inadequate stabilisation
What are the three types of bone callus that can form?
- Periosteal
- Medullary
- Endosteal
What are 5 clinical signs seen in animals with fractures?
- Dysfunction
- Pain
- Blood loss
- Nerve Injury
- Perforation of adjacent organs
What do we use to classify fractures?
- Location, direction & number of fracture lines
- Displacement of major bone fragments and stability
- Open or Closed
- Whether the fracture fragments can be reconstructed to provide load sharing
Why are fractures classified?
- Allows detailed & concise communication between vets
- Allows comparison of techniques when similar fractures are treated
- Allows assessment of the forces that lead to injury and affects the stability of repair
- Helps predict diagnosis, likelihood of infection & difficulty, complications of treatment
Describe a descriptive classification of fractures…
- Complete vs. Incomplete
- Displacement
- Single vs. Complex
- Open vs. Closed
- Bone involved
- Region of bone involved
What is a complete fracture?
Cortex fracture circumferentially
What is an incomplete fracture?
One cortex cracked, one bent
OR…
Fissure extending down the shaft, with the periosteum intact