Abstract
Background: In total knee arthroplasty (TKA), postoperative pain control affects patient recovery and satisfaction. Periarticular injection with a multimodal protocol has been reported to be effective for pain control. There have been few studies describing only single periarticular injection using various kinds of medications for TKA. In this study, we assessed the efficacy of single periarticular injection compared with epidural infusion on postoperative pain and analgesic requirements after TKA.
Methods: Sixty-one female patients with osteoarthritis were randomized into two groups to receive either intraoperative single periarticular injection with ropivacaine, morphine, epinephrine, methylprednisolone, ketoprofen, and saline (Cocktail group), or continuous epidural infusion for three days postoperatively (Epidural group). For rescue analgesia, intravenous patient-controlled analgesia with morphine was used for 24 hours postoperatively. The intensity of knee pain (0-100 mm on visual analog scale (VAS), for 1 to 21 days postoperatively), morphine requirements (for 24 hours), and side effects were recorded.
Results: VAS for pain at rest was lower in the Cocktail group than in Epidural group on postoperative day (POD) 1, which was statistically significant (10.3 vs 39.6, p < 0.05). On POD 2, POD 3, POD 4 and POD 5, the VAS in the Cocktail group was lower, but the differences were not statistically significant (p = 0.317, 0.364, 0.332, and 0.097, respectively). After that, and up to POD 21, there was no further statistical difference of VAS for pain between the two groups. Morphine consumption during the first 24 hours was lower in the Cocktail group compared to Epidural group (212 vs 451 μg, p < 0.05). There was no statistical difference between the two groups with respect to the incidence of side effects.
Conclusions: Periarticular injection with multimodal medications provided superior pain relief and reduced morphine consumption compared with continuous epidural infusion after TKA.
