[Cryotherapy as analgesic technique in direct, postoperative treatment following elective joint replacement]

The application of crushed ice or hydrogenated silicate, a micro-crystalline substitute has been used as a method to treat posttraumatic and postoperative irritations of the locomotor system for a long time. Closed systems using pumps can be viewed as further development as they enable continuous, water-free cooling of operating areas. The analgetic effect of postoperative cold therapy was evaluated in a prospective clinical trial, including 312 patients after total knee or hip arthroplasty. Conventional cold packs, consisting of microcrystalline silicate were compared to a continuous applicable closed system. Continuous cryotherapy resulted in a depression of skin temperature to 12 degrees C, whereas intermittent cooling only caused a mean temperature decrease of 1 degree C. Clinically continuous cold application leads to a more than 50% decrease of analgetic demands in both, systemic and regional application (p < 0.001). This observation was found in a significant correlation with patient's pain sensation as well as primary range of motion. Intermittent cryotherapy was found to be ineffective in postoperative pain relieve in hip- and adequate in knee arthroplasty patients. We could not report an influence on postoperative blood loss, as discussed in previous reports.