Total knee arthroplasty (TKA) is one of the most performed orthopedic surgical procedures in the world, with more than 1 million procedures annually in the United States. Acute postoperative pain is intense and functional recovery is slow — factors that directly impact patient satisfaction and hospital costs. Multimodal analgesia (combination of NSAIDs, opioids, local anesthetics, and nerve blocks) is the current standard, but it has limitations: gastrointestinal adverse effects, opioid dependence, and incomplete functional recovery. A network meta-analysis published in Frontiers in Neurology in March 2024 evaluated four acupuncture modalities as adjuncts to multimodal analgesia in TKA, pooling 41 randomized controlled trials and 3,003 patients.
The study compared four modalities: conventional acupuncture (ACU), electroacupuncture (EA), transcutaneous electrical acupoint stimulation (TEAS), and auriculotherapy with acupuncture (AAT) — all as adjuncts to standard multimodal analgesia (MA). The outcomes evaluated were: pain intensity by VAS at different time points (1, 3, 7 days postoperatively), knee function by the HSS scale (Hospital for Special Surgery), opioid consumption, postoperative nausea/vomiting (PONV), and adverse events. The analysis used a random-effects model with a Bayesian approach and calculated SUCRA rankings for each intervention in each outcome.
MAIN RESULTS — 41 RCTS, 3,003 PATIENTS
Each modality has its own profile of excellence
The most clinically relevant finding of this NMA is that the four acupuncture modalities complement rather than compete with each other — each leads in a different outcome, allowing an integrated and personalized therapeutic strategy. TEAS (Transcutaneous Electrical Acupoint Stimulation) showed the best analgesic control on postoperative day 7 (SMD=0.67, 95% CI 0.01–1.32), a period when the patient is generally already in intensive rehabilitation with physical therapy. Conventional acupuncture (ACU) led in functional knee recovery on the HSS scale (SMD=6.45), closely followed by EA (SMD=4.89) and TEAS (SMD=5.31) — all superior to multimodal analgesia alone. Auriculotherapy (AAT) stood out in the safety outcome, with the lowest adverse event rate, making it ideal for high-risk patients or those with multiple comorbidities.
Reduction of opioid consumption: a strategic implication
An important secondary outcome of this meta-analysis was the reduction in postoperative opioid consumption with the addition of acupuncture modalities to multimodal analgesia. All four modalities contributed to opioid sparing, with TEAS and EA showing the best results in this outcome. In the context of the global opioid crisis, this morphine-sparing property has important clinical and public health implications. The 20–30% reduction in post-TKA opioid consumption translates to lower incidence of nausea/vomiting (PONV), lower risk of postoperative ileus, faster hospital discharge, and lower risk of dependence in the late postoperative period.
Frequently Asked Questions
Acupuncture with needles should be performed at a distance from the surgical wound during the first weeks of healing — periarticular points should avoid the incision área and surgical flaps. For the immediate postoperative period (first 48–72 h), TEAS (electrical stimulation on the skin without puncture) is the safest alternative, since there is no risk of wound contamination. From the second or third week onward, when primary healing is consolidated, conventional acupuncture can be progressively introduced at periarticular points using appropriate sterile technique.
The included studies typically used between 3 and 14 sessions, with greater effect observed in protocols of 10–14 sessions over 4–6 weeks. Duration should be individualized by the medical acupuncturist according to clinical course: patients with good response in the first sessions may complete the protocol in 6–8 weeks, while more complex cases (severe obesity, associated fibromyalgia) may benefit from longer protocols.
No — acupuncture is an adjunct, not a substitute. Physical therapy remains the central pillar of post-TKA functional rehabilitation, responsible for recovery of range of motion, muscle strengthening, and gait training. The role of acupuncture is to enhance physical therapy: by reducing postoperative pain and edema, it allows the patient to better tolerate physical therapy exercises and engage with greater intensity. The best functional results (SMD=6.45 on the HSS scale) were obtained precisely when acupuncture was combined with multimodal analgesia — which includes physical therapy — and not as an isolated intervention.
Founded in 1989 by physicians trained at the University of São Paulo (USP) and specialized in China, CEIMEC is a Brazilian national reference in the teaching and practice of medical acupuncture. With more than 3,000 physicians trained over 35 years, it collaborates with HC-FMUSP and is recognized by the Brazilian Medical College of Acupuncture (CMBA/AMB).