1. Concepts of Basic Casting
Developed by:
Michael Gill, OT/SC
Sponsored by:
GILTECH, LTD.

2. Overview Objectives Immobilization Historical Perspective
Cast Materials
Comparison of Casting Materials
Application of Casts
Cast Modifications
Types of Casts
Potential Complications
Patient Care
Cast Removal

3. Objectives
Upon completion of this educational program, participants should be able to:

4. Objectives
Explain the options for external immobilization of orthopaedic injuries.
Differentiate among the various types of commercial casting materials.
Outline the steps involved in the application of plaster, synthetic, and thermoplastic casts.

5. Objectives
Describe the anatomical sites where casts are used to immobilize upper and lower extremity injuries.
Discuss potential complications and nursing interventions associated with orthopaedic casting.

6. Objectives
Outline the care and instruction which must be provided to patients who are wearing casts.
Describe the techniques available for cast removal.

7. Immobilization

8. Immobilization Prevents displacement, angulations, shortening.
Prevents movement of bony fragments.
Permits normal healing.
Relieves pain.
Permits earlier use of limb.

9. Casting

10. Casting
A rigid encasement that surrounds a fracture area. It must extend far enough on either side of the fracture to ensure immobility of the site. Casts are often made of plaster of Pars, but can also be formed from synthetic materials. They can be molded precisely to fit the contours of the affected area.

11. Casting
Primary Casting is used for the initial treatment of a fresh fracture. These are usually made from Plaster of Paris.
Secondary Casting replaces the primary cast. Synthetic materials, such as fiberglass are most often used.

12. Bracing

13. Bracing
Bracing may be used to secure a fracture while leaving the adjacent joints free to move. It may be applied once the acute symptoms of a fracture, such as pain and swelling, subside. Permitting the patient to retain joint function has been shown to reduce rehab time and stimulate healing.

14. Traction

15. Traction
Traction is defined as the application of force to any body part for the purpose of restoring alignment following a fracture, overcoming deformity to relieve muscle spasms or pain, and/or maintaining alignment while a fractured bone heals.

16. Traction
Skin traction – the pull is applied directly on the skin and subcutaneous tissues and indirectly to bones.
Skeletal traction – applied directly to the bone by means of a pin or wire.

17. Historical Perspective

18. Historical Perspective
Egyptians – immobilized fractured extremities with primitive casts made of linen bandages stiffened with gum.
Hypocrites - in the fourth century B.C, immobilized injured extremities by applying bandages that were made rigid with waxes and resins.

19. Historical Perspective
Arabs – probably the first to use plaster casts to treat fractures.
Europeans – first reported use of plaster casts.
Antonius Mathysen – Dutch Army surgeon. First treated battle wounds with bandages impregnated with plaster of Paris in 1852.

20. Historical Perspective
1927 – modern plaster of Paris rolls were developed. A binder, usually consisting of starches, gums and resins, is used to adhere the plaster to the cloth.
Most recently, a variety of synthetic and thermoplastic casting materials have been developed.

21. Cast Materials

22. Cast Materials
The term “cast” can refer to the rigid outer shell only or both the shell and one or more of the undercast layers placed on the skin. The shell may be made from:
- Plaster of Paris
- Synthetics (e.g., fiberglass)
- Thermoplastic material

23. Plaster of Paris

24. Plaster of Paris
Standard to which all newer casting materials are compared.
Derived from gypsum, or calcium sulfate dihydrate.
When dehydrated, gypsum forms a white powder called plaster of Paris (anhydrous calcium sulfate).

25. Plaster of Paris
When this powder is soaked in water, it recrystallizes in an exothermic (heat releasing) reaction and gypsum is formed. As it sets, the plaster hardens into whatever form it was molded into before setting.
Plaster casts are constructed from bandages impregnated with plaster of Paris.

26. Plaster of Paris
When dry, a plaster bandage resembles a roll of bandage with white powder adhering to it.
When water is added, the plaster becomes highly moldable and paste-like.
Consistency varies from creamy to coarse, depending on type and chemicals introduced. Creamy plaster tends to be less durable.

27. Plaster of Paris
The ultimate strength of a plaster cast can also be improved by addition of resins.
Always follow the manufacturer’s recommendations for storage and rotation of plaster rolls.

28. Undercast Material for Plaster Casts

29. Undercast Material for Plaster Casts
Stockinet
A knitted sleeve used under plaster casts.
Made of cotton.
Rolls of various diameter, may be as long as 25 yards
Cut longer than anticipated cast length.
Wicks moisture away from skin.

30. Undercast Material for Plaster Casts
Cast Padding
Made of cotton, rayon, or blend.
Used over stockinet, under plaster casts.
Felt or rubber used for additional padding.
Available in various lengths, on rolls.
Protects against rubbing and ulcerations.
Cushions, but allows cast to conform well.

31. Elastic Plaster Bandages

32. Elastic Plaster Bandages
May have rubber elastic fiber added.
Hugs contours and bony prominences.
Can be intimately molded against body part.
No need to tuck, “glove like” fit.
More expensive
Not used alone in weight bearing casts.
Ideal initial layer in any cast.

33. Synthetic Casts

34. Synthetic Casts Fiberglass casts were introduced in the 1950s.
Originally required activation with an acetone solvent.
Frequent reports of allergic reactions to the solvent led to the introduction of water soluble materials.

35. Synthetic Casts
Today, synthetic casts are made of knitted fiberglass, polyester, or a polyester/cotton blend.
Dipped in room temperature water and applied in manner similar to plaster cast bandages.
Water activated polyurethane resin.
Forms a polymer that links to itself.

36. Synthetic Casts Extremely high strength-to-weight ratio.
Once activated, resin will not be affected by water again (water resistant).
Mostly used for secondary casting
Enhanced patient ambulation and comfort.
Comes in a variety of types/colors/patterns.
Follow manufacturers directions for storage.

37. Undercast Material for Synthetic Casts

38. Undercast Material for Synthetic Casts
Synthetic Stockinet
Used instead of cotton.
Less capacity to hold water than cotton.
Wick moisture out through cast and promote more rapid evaporation.
Barrier between skin and casting material.

39. Undercast Material for Synthetic Casts
Cast Padding
Will not hold moisture.
Provides cushioning between cast/skin.
Repels water.
Maintains it’s bulk.
Dries quickly.

40. Thermoplastic Casts

41. Thermoplastic Casts Heat sensitive plastics.
Become soft and malleable.
Can be cut and molded to form intricate designs when heated.
When cooled, are lightweight, strong, durable, and radio lucent.
Roll or sheet form, sheets easier to use.
Primarily used to construct splints and braces.

42. Thermoplastic Casts
Classified by temperature required to soften the plastic.
Only low temp thermoplastics can be placed directly on the skin or over a stockinet and be molded. Can be heated in water, hydroculator, or oven at degrees F.

43. Thermoplastic Casts
Medium and high temp thermoplastics can burn the patient and the surgeon or orthopaedic technician. Therefore, cast made of these materials are formed by using previously made plaster molds and the hot material is handled with asbestos gloves.

44. Undercast Material for Thermoplastic Casts

45. Undercast Material for Thermoplastic Casts
Low temp thermoplastic casts are applied directly to the skin.
A stockinet is frequently used as an undercast material if long-term wear is anticipated.
Cast padding is not required.

46. Comparison of Casting Materials

47. Comparison of Casting Materials
Plaster of Paris
Material of choice for primary casting.
Moldable, economic, familiar to surgeons.
Easy to reinforce and remove.
Rarely cause skin irritation.

48. Comparison of Casing Materials
Plaster of Paris
Not water resistant.
Relatively heavy, low strength-to-weight ratio.
May take 2-3 days to reach weight bearing strength.
Messy, clogs sink drains.
May break down around a walking heel.
Repairs are difficult.

49. Comparison of Casting Materials
Synthetics
Lightweight, porous, water-resistant.
Strong and durable.
Achieve Weight-bearing strength quickly with relatively lightweight casts.
Easy to apply.
No need to remove during radiographic procedures.

50. Comparison of Casting Materials
Synthetics
More expensive in cost per roll.
Considered less moldable than plaster.
Can’t be reheated and remolded.
Patient may be allergic to material.

51. Comparison of Casting Materials
Thermoplastics
Comfortable, lightweight, strong, durable.
Easy to remove
High strength-to-weight ratio.
Water-resistant and permeable.
Can be reheated for additional molding.
Don’t require padding.

52. Comparison of Casting Materials
Thermoplastics
Not as comfortable as plaster or fiberglass.
Initial unit cost is higher.
Some may be awkward to apply.

53. Application of Casts

54. Application of Casts
Cast application is as much an art as a science; each practitioner has his/her own technique. The following are general guidelines only.
Prior to application of a cast, it’s important to discuss with the patient the purposes of the cast, the area to be encased, probable length of time, and any special concerns or care requirements.

55. Plaster Casts

56. Plaster Casts Assemble all of the materials needed.
Don protective gear.
Examine the area to be casted.
Apply a stockinet.
Apply cast padding.
Remove 1st casting bandage from package.
Fold back leading edge of plaster, roll.

57. Plaster Casts 8. Submerge bandage 5 secs, remove water.
9. Place bandage roll on cast padding.
10. Roll bandage in spiral pattern.
11. Apply bandage smoothly, firmly, rapidly.
12. Use a figure 8 pattern for 90 degree angles.
13. Gently rub successive layers of bandages.
14. Apply layers of plaster bandages.

58. Plaster Casts 15. Splinting to reinforce, if necessary. 16. Setting.
17. Drying.
18. Trim cast as necessary.
19. Cushion the margin with stockinet ends.
20. Observe patient for discomfort.
21. Handle wet cast with care.

59. Synthetic Casts

60. Synthetic Casts Assemble materials Don Protective gloves.
Examine body part to be casted.
Apply stockinet.
Apply cast padding.
Dip in water for 3-5 secs at degrees.
Squeeze roll firmly 4-5 times.
Remove roll from water.

61. Synthetic Casts Apply casting tape quickly. Tuck tape if necessary.
Splint if necessary.
Setting.
Just prior to setting, mold cast.
Drying.
Reinforce or patch any time as needed.

62. Thermoplastic Casts

63. Thermoplastic Casts Assemble all necessary materials.
Examine body part to be casted.
Determine initial design.
Trace paper pattern.
Ventilate material if desired.
Heat the sheet.
Cut thermoplastic material.

64. Thermoplastic Casts 8. Clean and dry surfaces.
9. Reheat sheet if necessary.
10. Apply cast directly to the skin.
11. Setting.
12. Reheat for further molding if needed.
13. Velcro fasteners or snaps.
14. Create permanent hinge.

65. Cast Modifications

66. Cast Modifications
A cast window is a square or rectangular area cut and removed from the cast, often to expose a surgical wound or areas where symptoms of pressure develop. The cutout window can be reinserted and secured with adhesive tape or an elastic bandage. If pressure is an issue, replace window with a foam pad to prevent skin bulging.

67. Cast Modifications
When significant swelling is expected, the cast may be split longitudinally (bivalved) after it is applied and before swilling occurs, A 1 cm wide strip of casting material is removed, extending from the distal end to within 2-3 cm of the proximal end of the cast. The bivalved plaster shells are secured with straps, Velcro closures, or specially designed cast closure devices.

68. Cast Modifications
A walking heel or cast shoe may be applied to protect the cast when the patient walks.
Rubber cast soles can be wrapped directly into walking casts when formed or held in position with adjustable straps. They support the toes and foot, improve walking ability.
Cast hinges can be added for joint mobility.

69. Types of Casts

70. Short Arm Cast

71. Short Arm Cast Cast Dimensions Fits like a glove.
Immobilizes injured part only.
Full range of motion at elbow (Oppose all fingers to thumb).
Distal border – At distal palmer crease
Proximal border – 2 finger breadths below elbow.

72. Short Arm Cast Stockinet 1. Selection
Width doesn’t restrict widest part of limb.
Length allows extra stockinet to roll back at distal end.
2. Cut thumb holes 3 inches from distal end and ½ inch into stockinet.

73. Short Arm Cast
Padding
Size – use largest width that can be controlled.
Typically wrap with 2 layers, except bony prominences, where 4 to 5 layers are required.

74. Short Arm Cast Casting Tape
1. Lower arm cast, 2-inch tape for older children, 3-inch tape for most adults
2. Set extremity in neutral position.
Wrist in slight dorsal flexion.
Neutral ulnar radial deviation
3. Wear gloves.

75. Short Arm Cast Dip Technique 1. Use room-temp water in bucket.
2. Dip tape, squeeze 3 times and remove immediately. Tape sets in 3 minutes.
3. To prolong working time, dip and immediately remove without squeezing.
4. For longest working time. Use rolls right out of pouch. Use spray bottle.

76. Application Technique
Short Arm Cast
Application Technique
1. Wrap spirally, overlapping by ½.
2. Use pinch technique between thumb and forefinger.
3. Roll back stockinet at proximal end and capture it with tape.
4. Roll back stockinet at distal end and capture it with tape.
5. Using palms, mold cast with wet gloves until set.
6. Avoid any fingertip pressure.

77. Short Arm Cast Removal Technique 1. Materials needed: Towel under cast
Safety glasses
2. Keep saw blade perpendicular.
3. Maintain control with thumb or finger on cast.
4. Use in and out motion to avoid heat build-up.
5. Bivalve cast along radial and ulnar borders.

78. Thumb Spica Cast

79. Thumb Spica Cast Stockinet 1. Selection
Wide enough to not restrict widest part of limb
Extra length to roll back at both ends.
2. Cut thumb hole 3 inches from distal end and ½ inch into stockinet.

80. Thumb Spica Cast Padding
Size – use largest width that can be controlled.

81. Thumb Spica Cast Dip Technique 1. Use room temp water
2. Tape sets in 3 minutes.
3. To prolong working time, apply tape without dipping.
4. Cast cures to functional strength in 20 minutes.

82. Application Technique
Thumb Spica Cast
Application Technique
1. Place hand in “pop can” position.
2. Use 2” stockinet for the arm, 1” for thumb.
3. Use identical padding as for short arm cast.
4. First Tape:
For average adult, 2 rolls or 2” or 1 roll each of 2” and 1” tape.

83. Thumb Spica Cast
For prolonged working time, don’t dip 1st roll in water.
Cut ½- ¾ way through tape when wrapping thumb for more comfortable fit.
Wrap & cut 3 times around thumb
Finish cast in normal fashion.

84. Thumb Spica Cast 5. Second Tape: Dip once and squeeze.
If you work fast, dip and squeeze 3 times.
Repeat thumb cut and wrap technique as for 1st tape.
6. Fold back stockinet at proximal and distal borders.
7. Finish and mold cast.

85. Boxer Cast

86. Boxer Cast Cast Dimensions
Full range of motion at elbow. Should have ability to oppose 1st & 2nd digits to thumb.
Distal border – tip of 5th digit.
Proximal border – 2 finger widths below elbow.

87. Boxer Cast
Stockinet
1. Width - shouldn’t restrict widest part of limb.
2. Length – allow extra to roll back at distal and proximal borders.
3. Cut thumb hole 3 inches from distal end and ¼ inch into stockinet.
4. 2 pieces of 2”, 5” to 6” in length. Cut 1/3 upward on both sides of 1 6” & 1/3 on 1 side of other piece.

88. Boxer Cast
Padding
Size – use greatest width that can be controlled ( 2” or 3”).
Wrap 1½ layers. Bony prominence may need 2 – 3 layers.

89. Boxer Cast Casting Tape 1. 2” or 3” should suffice.
2. Set extremity in neutral, functional position (wrist – slight dorsal flexion, MCPs flex at 90 degrees)
3. Buddy tape 4th & 5th digits with cotton between them.

90. Boxer Cast Application
1. Place 6” stockinet (with 2 slits) over buddy taped fingers.
2. Add stockinet that extends to the elbow. (trim back to MCPs).
3. Wrap padding spirally overlapping by ½, distally to proximally, and 6” stockinet over thumb rolling down to make a thumb cushion.

91. Boxer Cast
4. Wrap casting tape (usually 2”) distal to proximal. Mold cast into position.
5. Once cast has set, roll stockinet back over cast material and use second roll to cover the ends.

92. Long Arm Cast

93. Long Arm Cast Indications
For treatment of both bones of forearm and treatment of a supracondylar fracture of the humerus.
Cast Dimensions
Distal to palmar crease and proximal to axilla.
Stockinet
Use 2”, leave enough distally and proximally to roll back over cast.

94. Long Arm Cast
Padding
Begin just distal to palmar crease wrapping spirally, overlapping ½ “ to axilla.

95. Long Arm Cast Application
1. Use 2 rolls or 3” casting tape for average adult.
2. Roll on 1st roll distally to proximally, overlapping by ½”.
3. Roll stockinet over cast.
4. Apply 2nd roll of tape identically to 1st roll.
5. Mold cast.

96. Short Leg Walking Cast

97. Short Leg Walking Cast Cast Dimensions
Distal end just beyond metatarsal head.
Proximal to tibial tuberosity just below knee.
Back of cast low to allow knee flexion.

98. Short Leg Walking Cast Stockinet
1. 3” size for large children and adults.
2. Length allows for distal and proximal roll back of stockinet over cast.
3. Accommodate ankle dorsiflex with 1 heel-to heel cut and overlap of stockinet material.

99. Short Leg Walking Cast Padding 4” size for large children and adults.
Begin application distally.

100. Padding Application Technique
Short Leg Walking Cast
Padding Application Technique
1. Place foot and ankle in neutral position.
2. Extend pad beyond metatarsal heads.
3. Wrap spirally, overlapping by ½ , Typically wrap 2 layers.
4. Apply extra padding on lateral side of fibular head to protect peroneal nerve.
5. Use accessory padding over Achilles area, lateral and medial malleolus, and heel.

101. Tape Application Technique
Short Leg Walking Cast
Tape Application Technique
1. First Tape:
To extend working time, don’t dip roll.
Wrap distally from metatarsal heads up to the knee, overlapping by ½.
Roll back stockinet at knee over top of tape.

102. Short Leg Walking Cast 2. Second Tape: Weight bearing roll.
Dip quickly in water. Squeeze once.
Wrap from metatarsal heads to just above ankle.
Reinforce around the heel.
Dorsal toe cutout:
- Cut material on either side of toe.
- Cut transversely across foot.
Remove excess material. Fold stockinet.

103. Short Leg Walking Cast 3. Third Tape:
Dip in water and squeeze 3 times.
Wrap distal to proximal, incorporating stockinet.
Mold cast until set.
4. Options
Reinforce weight bearing portion with reinforcing strip.

104. Strap-on standard cast shoe
Short Leg Walking Cast
Strap-on standard cast shoe
1. Allow extra minutes for set up of 1st roll before weight bearing.
2. Use for all ambulation on weight bearing casts.
Removal Technique
1. Follow removal steps for short arm casts.
2. Bivalve medially and laterally.
3. Cut to stockinet.

105. Long Leg Cast

106. Long Leg Cast Indications
For fractures and dislocations of knee/ankle joints, fractures of the tibia, fubula, and distal end of femur.
Cast Dimensions
Distal end just beyond metatarsal head.
Proximal end 1 ½” to 2” distal to groin.

107. Long Leg Cast Stockinet 1. 3” for adults, 2” for small children.
2. Allow enough length distal and proximal to roll back over cast.
3. For ankle dorsiflexion, make a transverse cut from malleolus to malleolus.

108. Long Leg Cast Padding 4” for adults, 3” for children.
Begin application distally, wrapping spirally.

109. Long Leg Cast
Position
1. Place foot and ankle in 90 degree of dorsiflexion and knee flex at degrees.
2. Wrap spirally distal to proximal, overlapping by ½.
3. Apply extra padding over bony areas.

110. Long Leg Cast Application
1. Wrap distally from metatarsal head up to groin, overlapping by ½.
2. Roll back stockinet at groin over top of cast material.
3. Next layer should be wrapped from metatarsal head to ½” below cast padding. Reinforce around heel.
4. Mold cast until set.

111. Potential Complications of Casting

112. Potential Complications of Casting
Too tight a cast may result in irritation and pressure causing skin inflammation, ulceration, nerve compression/malfunction.
Too loose a cast may cause fracture angulations, loss of alignment/apposition.
Insufficient padding may cause skin irritation, ulceration, and phlebitis.

113. Potential Complications of Casting
Poor patient compliance may result in damage. Be sure to instruct patients on proper maintenance.
Physical immobility can adversely affect every body system and psychosocial function in addition to causing atrophy.
Thermal burns.

114. Patient Care

115. Patient Care
Circulation in the body part distal to the cast. Check for finger/toes that are blue/cool.
Smoothness of cast edges. Repair rough or deteriorated plaster edges.
Discolored spots may indicate seepage from an underlying wound.
Pain. Report any patient complaints of pain.

116. Patient Care
Itching under the cast. If cast edges are loose enough, this common problem may be relieved by massaging skin with alcohol or scratching device.
Impaired mobility. Observe patient’s range of motion and ability to move.

117. Patient Care
Instruct patient to report any pain, numbness, coldness, or discoloration in the limb. Also, instruct patient in appropriate cast care.
Cast material water resistance varies:
- Plaster casts are not water resistant.
- Synthetic casts are but undercast material
in not.
- Thermoplastic casts are and have no undercast
material.

118. Cast Removal

119. Cast Removal
Cast removal is a very safe procedure. Casts are usually removed using a cast saw, a cast spreader, and bandage scissors. The cast saw may be fitted to a vacuum, which uses a hose to remove debris.
If the patient is an infant or seems intimidated by the cast saw, soak the cast in water and remove with hand or scissors. Synthetic casts cannot be removed by soaking.

120. Procedure for removal by cast saw:
Cast Removal
Procedure for removal by cast saw:
Judge depth of penetration.
Short up and down strokes.
Insert cast spreader into groove.
Alternately cut and spread cast.
Remove the padding.

121. Final Thoughts
Cast immobilization is a vital part of the management of fractures and other orthopaedic injuries. If a fractured limb is properly reduced and immobilized, if damage to the surrounding tissues is not too severe, and if the patient conscientiously follows instructions for cast care and exercise, a positive outcome can be anticipated

122. Summary Objectives Introduction Historical Perspective Cast Materials
Comparison of Casting Materials
Application of Casts
Cast Modifications
Types of Casts
Potential Complications
Patient Care
Cast Removal