Efficacy of betamethasone valerate medicated plaster on painful chronic elbow tendinopathy: a double-blind, randomized, placebo-controlled trial

Objective: to investigate the efficacy and safety of a medicated plaster containing betamethasone valerate (BMV) 2.25 mg in patients with chronic elbow tendinopathy. Methods: randomized, double-blind, placebo-controlled study with assignment 2:2:1:1 to BMV medicated plaster applied daily for 12 hours, daily for 24 hours or matched placebo. 62 patients aged >= 18 years with chronic lateral elbow tendinopathy were randomized. The primary efficacy variable was pain reduction (VAS) at day 28. Secondary objectives included summed pain intensity differences (SPID), overall treatment efficacy and tolerability. Results: mean reduction in VAS pain score at day 28 was greater in both BMV medicated plaster groups, -39.35 +/- 27.69 mm for BMV12-h and -36.91 +/- 32.50 mm for BMV24-h, than with placebo,-20.20 +/- 27.32 mm. Considering the adjusted mean decreases, there was a statistically significant difference between BMV12-h and placebo (p=0.0110). Global pain relief (SPID) and overall treatment efficacy were significantly better with BMV. BMV and placebo plasters had similar local tolerability and there were few treatment-related adverse events. Conclusions: BMV plaster was significantly more effective than placebo at reducing pain in patients with chronic elbow tendinopathies. The BMV plaster was safe and well tolerated.