Fractures and Healing Flashcards
What is a comminuted fracture
A fracture with more than 2 fragments
What usually causes a transverse fracture
when a force is applied directly to the site at which the fracture occurs
What can cause a spiral or oblique fracture
a twisting force applied distant from the site of fracture (e.g. each end of a long bone such as a tibia)
Who do greenstick fractures occur in
children whose bones are soft and yielding
Describe the appearance of a greenstick fracture on x ray
the bone bends without fracturing across completely - the cortex on the concave side usually remains intact
What causes a crush fracture
compression force
where do burst fractures occur and how
short bones e.g. vertebra
strong direct pressure, usually occurs as a result of impacting of the discs
What causes an avulsion fracture
traction
a bony fragment is torn off by a tendon or ligament
What is a fracture dislocation or subluxation
a fracture which involves a joint and results in malalignment
What is an open fracture
a surface wound that communicates with a fracture
Why do open fractures need urgent treatment
They can become infected
When is a fracture termed complicated
wen there is involvement of important soft-tissue damage e.g. nerves, vessels or internal organs
When is a fracture impacted
when the fragments are driven into one another
Are impacted fractures stable or unstable
Stable
What is an unstable fracture
a fracture which is displaced or has the potential to displace
What is an intra-articular fracture
one in which the fracture involves the joint surfaces
What classification is used for epiphyseal injuries
Salter and Harris (I-V)
What is the commonest type of epiphyseal fracture
Type 2 - the fracture line runs across the epiphyseal line and the obliquely shearing off a small triangle of metaphysis
What types of epiphyseal fractures have a good prognosisi
The first 3 types
What might a type 3 epiphyseal fracture require and who does it occur most commonly in
Open reduction and pinning
older children and adolescents
What is the commonest symptom of a fracture
Pain
What are the 6 clinical signs you need to look for in a suspected fracture
Tenderness Deformity Swelling Local temperature increase Abnormal mobility or crepitus Loss of function
Why does swelling in a fracture occur
Gross swelling - due to vascular rupture
Small - due to haematoma, and due to inflammatory exudation
How many planes should X rays be taken in
at least 2 - at right angles
What are the benefits of using an Xray for fractures
It localises it and determines the number of fragments
Indicates the degree and direction of displacement
Provides evidence of pre-existing disease of the bone
May show foreign body
May who unsuspected fracture
May show air in the tissues - Penetrating injury
What is the ultimate aim of fracture healing
Cortex-cortex union
How are many fractures joined initially
By a cuff of provisional woven bone known as a callus
What is responsible for the slow growth of new bone across the fracture gap
Late medullary callus
What might inhibit late medullary callus
intramedullary internal fixation
Describe the appearance of the callus if a fracture is fixed rigidly
almost none is seen
Why do man fixation devices allow some movement to occur
Due tot he potential for rigid fixation to delay union
How long does clinical union of a long bone normally take in an adult
3-4 months
What happens after clinical union
Remodelling to produce cancellous and cortical bone with normal trabecular orientation
Describe how fractures heal
Ina similar way to soft tissue but the migrating cells have osteogenic potential and sometimes cartilage is laid down as an intermediate step
Describe the changes to a fracture site from onset - 12 months
Onset - break in periosteum and clot forms between 2 fragments
1 week - Clot retracts and active osteoblasts move in
3 weeks - cartilage and osteoid are laid down
6-12 weeks - Callus is formed
6 months - Callus size reduces and looks more normal
12 months - complete radiological union and cortex to cortex union
