Drug-Free Interventions to Reduce Pain or Opioid Consumption After Total Knee Arthroplasty A Systematic Review and Meta-analysis

Objective

To systematically review and meta-analyze evidence of nonpharmacological interventions for postoperative pain management after total knee arthroplasty. 

Results 

Of 5509 studies, 39 randomized clinical trials were included in the meta-analysis (2391 patients). The most commonly performed interventions included continuous passive motion, preoperative exercise, cryotherapy, electrotherapy, and acupuncture. Moderate-certainty evidence showed that electrotherapy reduced the use of opioids (mean difference, −3.50; 95% CI, −5.90 to −1.10 morphine equivalents in milligrams per kilogram per 48 hours; P = .004; I 2 = 17%) and that acupuncture delayed opioid use (mean difference, 46.17; 95% CI, 20.84 to 71.50 minutes to the first patient-controlled analgesia; P < .001; I 2 = 19%). There was low-certainty evidence that acupuncture improved pain (mean difference, −1.14; 95% CI, −1.90 to −0.38 on a visual analog scale at 2 days; P = .003; I 2 = 0%). Very low-certainty evidence showed that cryotherapy was associated with a reduction in opioid consumption (mean difference, −0.13; 95% CI, −0.26 to −0.01 morphine equivalents in milligrams per kilogram per 48 hours; P = .03; I 2 = 86%) and in pain improvement (mean difference, −0.51; 95% CI, −1.00 to −0.02 on the visual analog scale; P < .05; I 2 = 62%). Low-certainty or very low-certainty evidence showed that continuous passive motion and preoperative exercise had no pain improvement and reduction in opioid consumption: for continuous passive motion, the mean differences were −0.05 (95% CI, −0.35 to 0.25) on the visual analog scale (P = .74; I 2 = 52%) and 6.58 (95% CI, −6.33 to 19.49) opioid consumption at 1 and 2 weeks (P = .32, I 2 = 87%), and for preoperative exercise, the mean difference was −0.14 (95% CI, −1.11 to 0.84) on the Western Ontario and McMaster Universities Arthritis Index Scale (P = .78, I 2 = 65%). CONCLUSIONS AND RELEVANCE In this meta-analysis, electrotherapy and acupuncture after total knee arthroplasty were associated with reduced and delayed opioid consumption.