Study design and participants
ligament rupture, knee pain, trauma
CHRONIC PAIN
This blinded randomized study was approved by the Ethical Committee of the Shanghai Tenth People’s Hospital, Shanghai, China (No. SHSY-IEC-KY-4.0/19-79/01) and was registered with a clinical trials registry (ChiCTR2000041404). Written informed consent was obtained from all patients. This study was conducted between July 2019 and June 2020 and adhered to the applicable CONSORT guidelines.The inclusion criteria were as follows: (1) American Society of Anaesthesiologists (ASA) physical status I or II; (2) aged 20–70 years; and (3) elective knee arthroscopy surgery. The exclusion criteria were as follows: (1) known intolerance or contraindication for local anaesthetics, paracetamol, nonsteroidal anti-inflammatory drugs, or opioids; (2) difficulty in mouth opening, preventing the laryngeal mask airway from being placed; (3) chronic pain with oral opioids or other analgesics used ≥ 1 year; and (4) significant limitation of knee motion during the acute phase of trauma, ligament rupture, or knee pain.