Biswas A, et al. - In order to determine the relative contributions of adductor canal block and intrathecal morphine (ITM) to analgesia and functional recovery after total knee arthroplasty, researchers examined 3 groups of patients who received either a “sham” adductor canal block with 30 mL of normal saline or an adductor canal block with 30 mL of ropivacaine 0.5% with 1:400,000 epinephrine, or the adductor canal block with the active drug and 100 μg of ITM for unilateral total knee arthroplasty. Across all 3 groups, no difference was observed in either the primary outcome of Timed Up and Go (TUG) test on postoperative day (POD) 2, other immediate functional secondary outcomes, or in global functional outcome at 3 months postoperatively. Several positive secondary outcomes of lower pain scores and opioid requirements, as observed in this study, were indicative of an improved analgesic profile in the first 48 hours postoperatively when both adductor canal block and low-dose ITM (100 μg) were added to local infiltration analgesia.