Effectiveness of ice packs in reducing skin temperature under casts

Skin temperature lowering effects were measured after application of crushed ice packs to the surface of synthetic and plaster casts. The skin temperature of legs in synthetic casts decreased an average of 10.4 degrees C (range, 8.3 degrees-12.6 degrees) to a minimum temperature of 19.7 degrees C (range, 16.2 degrees-21.8 degrees), and the temperature of legs in plaster casts decreased an average of 11 degrees C to a minimum of 18.7 degrees C (range, 13 degrees-22.8 degrees). It took an average of 56 minutes (range, 40-80 minutes) for the legs in synthetic casts and 63.8 minutes (range, 26-116 minutes) for the legs in plaster casts to reach the minimum temperature. Cryotherapy is used clinically with the intention of lowering skin temperature and presumably decreasing the pain and swelling of a patient's injured extremity. The presence of a synthetic or a plaster cast does not eliminate the lowering effects of skin temperature when crushed ice packs are applied to the surface of the casts.