Figure 2. Percent withdrawal responses evoked by three strengths of von Frey filament. Filled bars represent (A) 10-, (B) 30-, and (C) 90-mN filaments. (D) Open bars represent the number of responses to acetone application of three trials (80%), applied to the plantar surface of the paw, before (baseline) and after a hole was drilled through the tibia. The data are plotted as vertical boxes with error bars showing the median and the 10th, 25th, 75th, and 90th percentiles (n = 8). *Significant difference (Wilcoxon's signed rank test, P < 0.05) from values obtained before the bone was damaged (baseline).