FNB in Meniscal Tear Under GA

The investigators will compare the results of sono-guided femoral nerve block in arthroscopic surgery for meniscal tear under general anesthesia

This study is a randomized controlled trial of 100 patients, who underwent history taking, physical examinations, x-rays, and MRI or ultrasonography, and were diagnosed with meniscal tear from september 2023 to august 2028. The 100 patients will be assigned to Group I (with femoral nerve block) or Group II (without femoral nerve block) under double-blinded randomization. The randomization will be performed by an independent nurse using a computerized random sequence generator. The operators who participated in the procedure will be blinded to the participant's information. Both group will undergo general anesthesia for arthroscopic meniscal surgery. After anesthesia, sono-guided femoral nerve block will be performed. The injection for group1 is 20 mL ropivacaine and for groupII is 20 mL 0.9% saline. A visual analog scale (VAS) for pain will be recorded 1, 3, 6, 12, 18, 24, 36, 48 hours after the operation. VAS scores range from 0 to 10, with 0 being no pain and 10 being the most severe pain ever experienced. Injection with ultrasonography will be performed by a single anesthesiologist. 3 orthopedic surgeons will perform the surgery.