PMID- 26900905 OWN - NLM STAT- MEDLINE DCOM- 20160502 LR - 20220410 IS - 1546-3141 (Electronic) IS - 0361-803X (Linking) VI - 206 IP - 4 DP - 2016 Apr TI - Does Reducing the Concentration of Bupivacaine When Performing Therapeutic Shoulder Joint Injections Impact the Clinical Outcome? PG - 805-9 LID - 10.2214/AJR.15.15132 [doi] AB - OBJECTIVE: Mixtures of local anesthetics and steroids are routinely injected intraarticularly to temporarily relieve joint pain, even though local anesthetics have been reported to cause chondrocyte death in a dose- and time-dependent manner. This study aimed to determine if intraarticular injections of bupivacaine 0.5% and bupivacaine 0.25% would provide similar pain relief. MATERIALS AND METHODS: All fluoroscopically guided glenohumeral joint injections performed using 2.5 mL of bupivacaine and 0.5 mL (20 mg) of triamcinolone acetonide over a 42-month period were included if a pain score was recorded before, 5-10 minutes after, and 1 week after injection. Pain reduction of more than 2 points was considered much improved clinically with pain reduction of more than 1 point considered the minimum clinically important difference (MCID) threshold. RESULTS: Statistically significant and much improved pain reduction was achieved using both bupivacaine 0.5% and 0.25% 5-10 minutes (-3.7 points; 95% CI, -3.4 to -4.0 points; p