Reduced opiate use after total knee arthroplasty using computer-assisted cryotherapy.

PURPOSE: Despite multimodal pain management and advances in anesthetic techniques, total knee arthroplasty (TKA) remains painful during the early postoperative phase. This trial investigated whether computer-assisted cryotherapy (CAC) is effective in reduction of pain and consumption of opioids in patients operated for TKA following an outpatient surgery pathway.

METHODS: Sixty patients scheduled for primary TKA were included in this prospective, double-blind, randomized controlled trial receiving CAC at 10-12 °C (Cold-group, n = 30) or at 21 °C (Warm-group, n = 30) during the first 7 days after TKA according to a fixed schedule. All patients received the same pre-, peri- and postoperative care with a multimodal pain protocol. Pain was assessed before and after every session of cryotherapy using the numerical rating scale for pain (NRS-pain). The consumption of opioids was strictly noted during the first 4 postoperative days. Secondary outcomes were knee swelling, visual hematoma and patient reported outcome measures (PROMs). These parameters were measured pre-, 1, 2 and 6 weeks postoperatively.

RESULTS: In both study groups, a reduction in NRS-pain after every CAC session were seen during the postoperative period of 7 days. A mean reduction of 0.9 and 0.7 on the NRS-pain was seen for respectively the Cold- (P = 0.008) and Warm-group (n.s.). A significant (P = 0.001) lower number of opioids were used by the Cold-group during the acute postoperative phase of 4 days, 47 and 83 tablets for respectively the Cold and Warm-group. No difference could be observed for secondary outcomes and adverse effects between both study groups.

CONCLUSIONS: Postoperative CAC can be in added value in patients following an outpatient surgery pathway for TKA, resulting in reduced experienced pain and consumption of opioids during the first postoperative days.