Experimental design and sample size
postoperative pain, NRS, sham‐acupuncture, pain
A participant‐blinded, randomized and sham‐acupuncture (SA) controlled clinical trial was applied. Previous studies have shown that 15 participants should be included in each group to ensure stable statistical effect for brain fMRI analysis (Qiu et al., The study lasted for 5 days: from postoperative day (POD) 3 to POD 7. Patients were instructed to completed postoperative pain diary by documenting the onset time, pain intensity (measure by NRS score), rescue medication use, and rs‐fMRI scanning, which collected at POD 3 and POD 7.