Using electroacupuncture to recover muscle strength in knee osteoarthritic patients after total knee arthroplasty: a study protocol for a double-blinded, randomized and placebo-controlled trial

Background: Total knee arthroplasty (TKA) has recently become an almost irreplaceable and effective means to relieve pain, reconstruct knee motor function and improve the quality of life of patients with end-stage knee osteoarthritis (KOA). However, the muscle strength after TKA is usually difficult to recover. Although electroacupuncture (EA) can enhance the muscle strength of lower extremity, there is hardly any literature on the effect of EA on the muscle strength of lower extremity in patients after TKA. To address this problem, this trial is intended to evaluate the efficacy of EA after TKA for recovering the muscle strength of lower extremity, esp. in the early post-TKA period.Methods/design: This is a double-blinded, randomized and controlled trial. It will be conducted between January, 2020 and June, 2020. A total of 94 participants with KOA will have undergone unilateral TKA and they will then be randomized into a treatment group and a control group, viz. the EA group and the sham EA group. The former will receive EA at acupuncture points of ST37, ST36, SP10 and SP9. The latter, the control group will receive sham EA at sham locations for the acupuncture points of ST37, ST36, SP10 and SP9. The participants will be given 5 sessions of treatment per day for 2 weeks. The primary outcomes include a change in the amount of muscle strength and the Hospital for Special Surgery (HSS) score at the second week from a baseline (POD 3). The secondary outcomes include a 6-minute walking test, Numerical rating scale (NRS), the Hamilton Anxiety Scale and additional use of analgesia. The additional outcomes include incidence of analgesia-related side effects and rate of participant satisfaction. Blinding of the participants will also be assessed. The participants will be asked to guess whether they have received EA after the latest intervention. Adverse events of EA will be documented and assessed throughout the trial.Discussion: EA is helpful for the recovery and enhancement of muscle strength of the lower limb after TKA.