Fig. 5. Effects of interscalene perineural ropivacaine infusion on passive shoulder elevation (A) and external rotation (B) the day after total shoulder arthroplasty. Range of motion is analyzed as the percentage of the surgeon-defined target the patient achieved. Data are expressed as median (  horizontal bar ) with 25th–75th (  box ) and 10th–90th (  whiskers ) percentiles for patients randomly assigned to the ropivacaine group (perineural ropivacaine from surgery through postoperative day 4) or the placebo group (perineural ropivacaine from surgery through 06:00 postoperative day 1 followed by perineural normal saline through postoperative day 4). For tightly clustered data (  e.g. ,  B , 08:00 and 13:00, ropivacaine group), the median approximated the 10th, 25th, 75th, and 90th percentile values because all subjects achieved 100% of their target angle.