Figure 2 -. Metrics of analgesic efficacy in 7 dogs with osteoarthritis treated with a single intra-articular injection of 10mcg of resiniferatoxin (RTX).

A. Pain interference scores are plotted for each invidivual dog treated with RTX. B. Aggregate data shows a significant decrease in interference scores at day 7 and day 21. C, D. Data are plotted similarly for the Canine Brief Pain Inventory pain severity scores, with a significant reduction observed at day 21 post-treatment relative to pre-treatment values. B, D. Bars show the range of individual values; *, p ≤ 0.05. E. Peak vertical forces were collected from force plate gait analysis in six of the seven dogs with osteoarthritis (5 knees and 1 elbow). There was significant improvement in lameness based on an increase in median peak vertical force in the treated leg from 46.0 (range 33.5 to 90.3) to 51.0 (range 38.0 to 102.7), three weeks following injection (p=0.027, Wilcoxon signed rank test). Statistics were performed on raw values for force measurements. Normalized values are plotted to correct for the wide range of initial force measurements, where each animal’s Day 0 measurements are taken as the 100% value. All six dogs show an improvement, with a median force at Day 21 equal to 112% of that at Day 0. A Mann Whitney test was also significant for normalized values (p=0.0022). F. The median time to owner-reported decrease in analgesic efficacy was 150 days (range 58 to 730 days).