Orthopaedics (Unit 5:Common fractures) Flashcards
Which part of bone has a nerve supply?
Periosteum (the membrane which covers the outside of bones)
What are the 8 signs of a fracture?
Pain Deformity Tenderness Swelling Tenderness Discolouration/bruising Crepitus Loss of function
How is swelling in a suspected fracture managed?
Raise above level of the heart
Why in a fracture does the disolouration change from dark to green then to yellow?
Dark = deoxygenated blood loss into soft tissues
As Hb in RBC is broken down and carried to liver by scavenger cells (colour changes to green then yellow)
What methods are used for investigating fractures?
X-ray Tomograms CAT US Radioisotope scanning
When is tomography useful when investigating fractures?
When area is difficult to distinguish due to overlapping structures (e.g. axis bone)
How does radioisotope scanning work?
Radioactive substance attaches to phosphate molecules that are taken up actively taken up by bone.
The more metabolically active bone is the faster it takes up radioactive substance.
On x-ray unusual metabolic activity can be seen (i.e. fracture)
When is radioisotope scanning useful?
When there is clinical doubt
In not acute situations (2 weeks after injury)
Which bone in particular is radioisotope scanning useful for?
Scaphoid
What should be commented on when describing a fracture?
Which bone & which side? Open or closed? Where on the bone is the break? What shape is the fracture? How many fragments What is the position of the distal fragment? Could it be pathological?
What are the 3 fracture shapes?
Spiral
Oblique
Transverse
In what kind of injury do spiral fractures occur and how severe are they?
Twisting (low energy)
Associated with little soft tissue damage to blood supply is preserved and healing likely
What might cause oblique or transverse fractures?
Buckling or direct injury to bone (high energy)
What are the 3 ways to describe how many fragments are present in a fracture?
Simple
Butterfly
Comminuted
How is the distal fragment of a fracture described?
In terms of displacement, angulation and rotation
How is he angulation of the distal fragment of a fracture described?
As either anterior, posterior, varus or valgus
What is a pathological fracture?
When a fracture seems out of proportion to the violence of the injury
What does the immediate management of a fracture involve?
Pain relief splintage
What can be used as an alternative to splintage to relieve muscle spasm in the early management of a fracture?
Traction (particularly useful in femoral neck fractures)
Which fractures are most likely to be at risk of large blood loss?
Major long bones (femur, tibia)
How many units will a patient with a femoral fracture lose?
2-3 units
How many units will the average person with a tibia fracture lose?
1 unit
How many units can an unstable pelvic fracture lose from the pelvic venous plexuses?
6 units or so
What is the treatment strategy for open fractures?
Clean them out and remove all dead tissue as soon as possible
Why are open fracture wounds sometimes left open?
If there is any doubt that closure can be achieved without any tension on the skin
If a patients wound is left open what extra treatment will they require?
Broad spectrum antibiotics
Tetanus protection
Why might a surgeon opt for a less than perfect result when managing a fracture?
The individual may be elderly or have poor bone quality and a less than perfect result might still allow them to do their daily activities (extensive treatment may have complications)
What process is used to return a bone to its normal position?
Reduction
How is closed reduction performed?
Traction on the distal fragment and relocation of the distal part back onto the proximal fragment by manipulation
Name 4 methods of holding a fracture
Casting
External fixation
Internal fixation
Traction
What factors should be considered when casting a fracture?
Maintained at proper length
Immobilise joint above & below
How does a cast work?
Controls joint movement and position so pressure is exerted at 3 points
What are the disadvantages of casting?
Heavy Immobilise joints Unable to examine Unable to use x-ray Muscle wasting (due to immobility)
Why do functional braces tend to be used after a few weeks?
They are highly dependent on a very accurate fit (gives time for pain and swelling to settle)
Which materials make ideal cast braces and why?
Glass fibre & polyurethane resin combinations (not so versatile but stronger and lighter)
What are the 2 stages of treating a fracture?
Reduction & Holding
Why are plaster splints highly unsuitable in high-energy fractures?
Assoc. with extensive soft-tissue damage so blood supply is severely damaged it is important to have an initial phase of soft tissue healing
Why is internal fixation hazardous to use in the management of fractures with extensive soft-tissue damage?
Ischaemia
Increases infection risk
How does an external fixator work?
Fixed to the bones by pins and stabilises limb by external scaffold (provides stability and allows access to soft tissues)
Name a downside to external fixation?
Pin sites are an easy route for infection
When is internal fixation used?
When a high degree of accuracy is required or other methods fail
What are the 4 types of internal fixation?
Apposition
Interfragmentary compression
Interfragmentary compression plus onlay device
Inlay device