Metal with sodium citrate

Mar 28, 2007 10:49 GMT  ·  By
Applying a gel to the Velcro-edged plastic bandage produces heat that welds the cast together and keeps the limb warm
   Applying a gel to the Velcro-edged plastic bandage produces heat that welds the cast together and keeps the limb warm

Good news for winter sport lovers.

A novel portable plastic splint that heat-molds itself around broken or wounded limbs is being designed to help skiers and others who enjoy taking part in extreme snow sports.

To use the splint, the patient must wrap strips of resistant but flexible plastic bandage tightly around the damaged limb and bind to one another employing Velcro.

After the plastic strips have been attached, a solution of sodium citrate gel is poured onto the splint. This chemical provokes a reaction with metal strips located inside the bandage, which determines the solution rapidly crystallize to generate a solid.

But the same chemical process releases heat, transmitting warmth to the injured limb. "This is the same reaction that is used in hand warmers," explains Paul Chamberlain, an industrial designer at Sheffield Hallam University in the UK. "It sets hard in around 5 minutes and heat-welds the plastic bandages together."

The splint is the result of the work of two of Chamberlain's students, Ching-Sui Kao and Geremi Durand, and Maxime Ducloux from the Institut Superieur de Plasturgie d'Alencon (ISPA) in Alencon, France.

Prototypes of the plastic splint are currently in production at ISPA. "The splint is primarily targeted at those who take part in snow sports. Around 450,000 people are injured each year, he says, most of whom suffer broken bones. Rescuers can usually reach these people, but providing warmth and support quickly is important, particularly if there is a long wait," said Chamberlain.

The splint is very handy, light and small, and can be easily carried by skiers or snowboarders in a rucksack and, in case of accident, as many strips as needed can be employed to cover and protect an injury.

After arriving at the hospital, the splint can be removed easily by doctors.

In March 2007, the splint gained the French Grand Prize at the Design and Innovation in Plasturgy competition.