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Effect of pressure applied during casting on temperatures beneath casts.
Brian J Deignan1, Joseph M Iaquinto, Scott M Eskildsen
1Department of Orthopaedic Surgery, Virginia Commonwealth University, Richmond, VA, USA.
Journal of Pediatric Orthopedics
|September 20, 2011
Summary
Molding casts increases skin temperature, posing a burn risk, especially with plaster and fiberglass combinations. Allow plaster casts to cool fully before molding to prevent thermal injury during application.
Area of Science:
- Orthopedics
- Biomedical Engineering
- Materials Science
Background:
- Burns and pressure sores are risks during cast application.
- Factors influencing these injuries include water temperature, padding, and cast layers.
- The impact of cast molding on temperature and pressure is understudied.
Purpose of the Study:
- To investigate if cast molding alters skin temperature.
- To determine if molding increases the risk of thermal injury or pressure necrosis.
Main Methods:
- An upper extremity model was used to measure pressure and temperature under casting materials.
- Padding, water temperature, and cast thickness were standardized.
- A 3-point mold was simulated using Fiberglass only, Plaster only, and Plaster/Fiberglass combination casts.
Main Results:
- Molding significantly increased temperature at application sites (P<0.0001).
- The Plaster/Fiberglass combination reached a peak of 47.9°C for 6 minutes.
- Temperatures did not reach the theoretical burn threshold; pressures were below harmful levels.
Conclusions:
- Cast molding pressure is a risk factor for burn injuries.
- Caution is advised when molding plaster splints overwrapped in fiberglass.
- Allow plaster to cool completely before molding to mitigate burn risks.
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