Acupuncture at the P6 acupoint for pain control in teenagers after triple repair surgery of patellar dislocation

INTERVENTION: Patients will be randomly allocated to an experimental group and a control group using a random number table. An indwelling press needle (0.2 X1.5 mm, Pyonex, Seirin Corporation, Shizuoka, Japan) will be used as an acupoint intervention in the experiment group. Bilateral Neiguan points are chosen as the acupoints. The experimental group will use real needles while the control group use false needles on the same points (false indwelling acupuncture). The needles will be indwelling for 72 hours. CONDITION: Pain control of patellar dislocation patients undergoing triple repair surgery ; Surgery PRIMARY OUTCOME: Pain intensity measured using visual analogue score (VAS) at 24 h, 48 h, and 72 h after the rehabilitation exercise SECONDARY OUTCOME: 1. Intensity of maximum and minimum resting pain measured using VAS at 24 h, 48 h, 72 h after surgery; 2. Total amount of additional analgesics used: the researchers will record the total amount of different drugs according to the doctor's order after surgery for 72 hours.; 3. Rate of analgesic side effects: if the patient displays any analgesic side effect symptoms, it will be recorded as "once", such as vomiting once or twice, etc.; 4. Satisfaction of patients with postoperative analgesia measured using a visual analogue scale at discharge; 5. Quality of life items disturbed by pain, measured by asking and recording the patients' subjective cognition every morning until the press needle is removed; 6. Successful blinding of patients: a special researcher will ask the question "Do you know which group are you in?" when they finish data collection. The researcher judges whether the blinding is a success or not according to the answer. INCLUSION CRITERIA: 1. Adolescent patients aged 13‐18 years 2. Patients who underwent this procedure for the first time 3. Patients with unilateral surgery 4. Junior high school or above 5. Patients undergoing general anesthesia 6. No previous history of opioid and psychotropic medication 7. No previous history of smoking or alcoholism 8. Informed consent