Plastering Basics

Casting Basics

Preparation
  • Before you actually begin with the patient, know exactly what it is that you are going to do, prepare your environment and arrange suitable supplies
Proximal and Distal Landmarks
  • Only restrict movement that is necessary by ensuring that the splint does not extend too far proximally or distally. See individual splints for specific landmarks
Position of Immobilised Segments
  • This is largely dependent on the pathology, but in general, unless the device is required to provide anatomical correction, then the joints should be splinted in a functional position to minimise stiffness
Moulding
  • Ensure that the splint is moulded to the contours of the limb to ensure a snug fit and prevent unnecessary movement
Stockinette
  • Stockinette is NOT compressive and can be used in casts under padding to provide a more pleasing finish. It is usually WHITE
  • Tubular bandage IS compressive and elastic and is used to control swelling in soft tissue injuries. It is usually pink or flesh coloured. DO NOT USE TUBULAR BANDAGE UNDER CIRCUMFERENTIAL CASTS
Padding
  • If using stockinette, use 2 layers of padding
  • If not using stockinette, use 2-3 layers of padding, regardless of it constructing a circumferential cast or a slab.
  • Do not pull the padding tight as you apply as it will thin out the padding
  • You should not be able to see the skin through the padding
  • Inadequate padding can cause burns when the plaster reacts to water or pressure areas
Plaster
  • Circumferential Casts
    • Use a roll size that fits horizontally in the patient's hand (for an upper limb cast) or is the width of the foot (for a lower limb cast)
    • Use 6-8 layers of plaster (if you overlap by 50% with each pass, this means that you would need to move up and down the limb twice to achieve 8 layers)
  • Slabs
    • Use a product that is about 60-70% of the circumference of the limb (roughly one size bigger than what you would use for a circumferential cast)
    • Use 12-14 layers of plaster
Synthetic Materials
  • Circumferential Casts
  • Slabs
    • Most pre-made synthetic products (such as Dynacast Prelude) will already have the required amount of padding and fibreglass / product. Simply trim to length (ensuring that the product does not protrude out of the padding - cut it at least 1cm short on both ends), wet and apply
Water
  • Ensure that the water is CLEAN and free from particulates and the temperature is COLD
  • The reaction once the plaster comes into contact with water produces heat which is proportional to the initial temperature of the water. Using even warm water can cause BURNS and less importantly, limits moulding time
Positioning
  • Have the patient adopt the optimal position prior to commencing the application of the splint and have them maintain this for the duration of the procedure
  • If the patient is struggling to maintain this position, consider having someone assist to hold the limb
Padding Application
  • Ensure that the padding is applied as smoothly as possible, without bumps, to avoid pressure areas
Plaster Application
  • When applying a cast roll, ensure that the bulk of the material is facing up, with at least some of the material unravelled and enough tension applied to keep the material taut
Moulding
  • Ensure that the splint is moulded to the contours of the limb between each roll, as well as on completion, to ensure a snug fit and prevent unnecessary movement
  • To give a satisfying smooth finish, use a wet glove to smooth out any blemishes
Technique
  • There are two ways a slab can be constructed from plaster - the "Sandwich" technique or using circumferential padding.
  • Circumferential Padding Technique
    • Having circumferential padding means that for this type of splint, there are more materials which can potentially compromise circulation (the padding and the bandages), however the plaster itself is not circumferential.
    • The major advantage to this method is that it is possible to join multiple splints together to provide support in more than one plane. A common example of this is a below knee backslab with a u-slab.
    • Technique
      • Apply 2-3 layers of circumferential padding (as if you were going to apply a circumferential cast
      • Measure out 12-14 layer of plaster for the slab
      • Wet, then wring the slab and apply it onto the padding
    Sandwich Technique
    • With the sandwich technique, there is no circumferential padding so there is less potential for neurovascular compromise.
    • It is easier to remove this type of splint
    •  Technique
      • Measure out the length of the splint and construct a slab of 12-14 layers of plaster (the sandwich filler)
      • Measure out 2-3 layers of padding, being just longer than the slab. Repeat this so that you have two sides (the bread)
      • Place one of the sides of padding on a table.
      • Wet, then wring the slab and place it on top of the first side of padding.
      • Place the other side of padding on top, ensuring that plaster is not exposed
  • Both Techniques
    • Apply to limb and bandage
    • Mould to shape of limb, taking care to avoid finger print dents
Technique
  • Use a product that is one size wider then the width of the limb
  • Measure out enough product for the splint and then add another 2cm
  • Remove the rigid material from the padding and trim and round the edges. Ensure that the rigid material sits at least 1cm in from the padding at either end as once the material hardens, it will damage the skin if protruding
  • Wet the synthetic material (preferably using a spray bottle, or alternatively run quickly under a running tap) and place back inside the padding.
  • Roll the splint up and wring to ensure even distribution of water
  • Apply to the limb, bandage and mould to the contours of the limb
Post Application Check
  • After applying a splint, appraise it. Check for length, joints including and movement of the free joints
  • ALWAYS perform a check of distal neurovascular function after application of any splint
Followup
  • ALWAYS provide the patient with written and verbal information regarding warnings and general plaster care, including instructions to return if they develop symptoms of neurovascular compromise or compartment syndrome
  • Most patients with with upper limb fractures should be immobilised in an elevation sling and ALL patients should be instructed to elevate their affected limb for at least 80% of the time for the first 2-3 days to minimise complications related to swelling
  • For patients with a circumferential cast, all patients who have had fractures that have been manipulated and those where there is potential for significant swelling should be instructed to return the next day for a cast check
  • All patients should be provided with information about when and who their ongoing followup will be with