[Cryotherapy as analgesic technique in direct, postoperative treatment following elective joint replacement]. / Kryotherapie als Analgesietechnik in der direkten, postoperativen Behandlung nach elektivem Gelenkersatz.

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.

[Effects of continuous cryotherapy on the surgically traumatized musculoskeletal system. Perioperative Cryotherapy Study Group]. / Effekte kontinuierlicher Kryotherapie auf den operativ traumatisierten Bewegungsapparat. Perioperative Kryotherapie-Arbeitsgruppe.

The in-vivo effectiveness of continuous cold pressure therapy was evaluated in 24 patients following elective knee or hip replacement surgery. A cooling of the skin surface down to 8 degrees C resulted in a reduction of the epifascial tissue temperature to 22 degrees C. A significant reduction of subfascial pressure in combination with decreased protein leakage via redovac output were notable. Observing a constant decreased pH-level increased oxygen saturation and reduced drop of base excess were interpreted as signs of reduced enzyme-linked metabolism activity. Clinically these findings were found in correlation to a 50% decrease of postoperative analgetic demands as well as a 20% increased range of motion level.