This study aims to evaluate the effect of the single-injection adductor canal block in patients receiving total knee arthroplasty under spinal anesthesia. The effect of the single-injection adductor canal and continuous adductor canal block in patients receiving total knee arthroplasty under general anesthesia has been well established. However, due to the residual effect of spinal anesthesia, the effect of the single-injection adductor canal block needs to be determined. The investigators hypothesize that the single-injection adductor canal block will decrease the total sum of 2h, 6h, 12h, and 24h pain score.
This study evaluates the effect of the single-injection adductor canal block in patients receiving total knee arthroplasty under spinal anesthesia.