The only two common nonpharmacologic interventions for postoperative pain management of total knee arthroplasty (TKA) that were associated with reduced and delayed opioid consumption were electrotherapy and acupuncture, according to a new systematic review and meta-analysis.
Three other frequently performed interventions analyzed in 39 published randomized clinical trials were continuous passive motion, preoperative exercise and cryotherapy. The study appeared in JAMA Surgery (2017;96:e8036).
“Opioid addiction is a national crisis that has been partially attributed to the liberal distribution of prescription opiates to better manage pain,” said co-author Tina Hernandez-Boussard, PhD, associate professor of medicine, biomedical data science and surgery at Stanford School of Medicine, in California. “Recent studies suggest that surgery is a possible gateway to opioid misuse and therefore identifying opioid-sparing approaches for postoperative pain management is a top priority. However, we found many commonly used nonpharmaceutical interventions for pain management had conflicting evidence on their effectiveness.”
The 39 randomized clinical trials of common nondrug interventions used in the meta-analysis involved 2,391 patients.
“We found moderate-certainty evidence that acupuncture and electrotherapy reduced or delayed patients’ opioid use, and low-certainty evidence that they reduce pain,” Dr. Hernandez-Boussard said. “Conversely, continuous passive motion and preoperative exercise had low-certainty evidence that they did not reduce pain or opioid consumption. We similarly found very low-certainty evidence that cryotherapy reduces opioid consumption and improves pain.”
Dr. Hernandez-Boussard said there are many ways to treat postoperative pain after TKA, and opioids might be the easiest option. “However, opioids may not be the best or the only treatment pathway. Our study suggests that the use of acupuncture and electrotherapy following total knee replacement may reduce or delay patients’ opioid use—a step toward curbing the opioid epidemic.”
But the meta-analysis found that acupuncture’s pain relief was effective only in the early postoperative phase.
Similarly, a Cochrane Review showed a small benefit of cryotherapy for pain at two days postoperatively, but not at days 1 and 3.
In addition, recent studies of continuous passive motion have failed to show improved functionality and rehabilitation. “A Cochrane article has also found no benefits from continuous passive motion on function, pain or quality of life following total knee replacement,” Dr. Hernandez-Boussard said.
She said because prescription opioid use is under national scrutiny and surgery is a possible gateway for addiction, “it is important to recognize effective alternatives to standard opioid therapy. Strong, unbiased evidence is needed to further support the results from our meta-analysis.”
In particular, more evidence supporting the association between acupuncture and electrotherapy on one hand and reduced or delayed opioid consumption on the other “is critical to inform appropriate postoperative pain management,” Dr. Hernandez-Boussard said. “Furthermore, because the quality of many studies analyzed for electrotherapy was very low, more high-quality, randomized clinical trials on long-term pain improvement after electrotherapy are needed.”