ULBD-treated patients had a significantly shorter length of postoperative hospital stay ( 55.1 vs. 100.8 hours , p = 0.0041 ) and time to mobilization ( 15.6 vs. 33.3 hours , p < 0.001 ) and were more likely to not use opioids for postoperative pain ( 51.9 % vs. 15.4 % , p = 0.046 ) .